Other Fuel System Problems of GMC Sierra 1500 - part 1

On [xxx], my vehicle suffered a complete loss of propulsion on the highway, displaying fault codes p0324 and p0016. The vehicle was taken to boyd's tar heel Chevrolet in roxboro, nc, where the engine block was replaced under the official gm 6. 2l engine safety recall. The truck was delivered back to me, and on the very first day I drove it—only 28 miles from my house—it suffered a secondary catastrophic loss of propulsion on the highway on [xxx]. The check engine light began flashing violently, indicating an immediate catalyst-damaging safety hazard, and the vehicle displayed fault code p0307 (cylinder 7 misfire). The dealership explicitly instructed me to stop driving the vehicle immediately, authorized the recovery, and told me to bill the tow directly to them. After towing the vehicle back to their facility, boyd's tar heel Chevrolet reversed their position. They are now attempting to hold me financially responsible for the towing fees, along with spark plugs, wiring, and fuel injector services, claiming the failure is due to routine maintenance. This represents a severe highway safety hazard, a direct failure of the manufacturer's official recall remedy, and potential dealer misconduct to avoid liability under the active NHTSA engineering analysis ea26005 for post-recall 6. 2l engine failures. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

See all problems of the 2021 GMC Sierra 1500 🔎.

The truck has shut off driving 5 times total and 3 different days, I was going down the interstate, and hwy. Speeds were ranging from 45 to 70, this is the 3rd time in the shop. At two different dealers.

See all problems of the 2024 GMC Sierra 1500 🔎.

Addendum to previous submission # 11760415. At 15,033 mileage again multiple codes present along with a rough running engine. Dealership service dept confirmed on 9/17/2026 verification of 10 active codes , 2 pending codes triggering check engine light. Onstar notification as well of engine issue. Prominently codes p0016 & p0340 lead the list. Pico testing was stated to have failed two out of 3 parameters. Officially stated now as an engine defect which is being directed to be replaced with a remanufactured , not new , motor. Very fortunate to not have experienced dramatic failure ( loss of propulsion ) at highway speeds far from home. Even though this vehicle warning's persisted prior to this ultimate conclusion it was insisted that ultimate failure was necessary before any resolution would be instituted. A safety conundrum if you will. A high probability safety risk of continued use ( based on historical data on this known engine failure risk ) to ‘ prove ‘ it would fail like many others already have. A fair assessment of my personal experience.

See all problems of the 2023 GMC Sierra 1500 🔎.

The truck shut off and would just crank. It threw the code p129f. And wouldn’t start up until after 15 minutes.

I am filing this complaint regarding a potentially serious safety defect involving my 2022 GMC Sierra 1500 denali four-wheel-drive with the v8 5. 3 engine. The vehicle had approximately 28,786 miles at the time of the incident. While traveling on an interstate highway in heavy traffic, my truck suddenly lost engine power. I was extremely fortunate that I was able to maneuver through traffic and get the vehicle onto the shoulder without being struck by another vehicle. A sudden loss of engine power under these conditions could easily have resulted in a serious or fatal collision. Immediately follow the incident onstar detected diagnostic trouble code p129f the vehicle was subsequently taken to an authorized gm dealership. The dealership diagnosed the problem and replaced the fuel pump power control module to repair the vehicle. I have since learned that general motors issued service bulletin 24 –na-139 concerning this condition. The bulletin specifically includes 2022 GMC Sierra 1500 vehicles and identifies loss of power stalling and dtc p129f among the possible symptoms. Gm states the condition may be caused by an internal short in the k111 fuel pump driver control module/fuel pump, power control module. I am particularly concerned that gm has been aware of this potential failure condition since at least 2024. A failure capable of causing a vehicle to suddenly lose engine power while traveling at internet speeds presents amsafety hazard not only to the occupants of the affected vehicle but also to surrounding motorist. I respectfully request that NHTSA review this issue including other owner complaints involving error code p129f, fuel pump power control, module failures, stalling, or sudden loss of power in affected GMC sierra and related to GMC vehicles and determine whether a safety defect investigation or recall is warranted. Vehicle: 2022 GMC Sierra 1500 denali four-wheel-drive engine: 5. 3 l v8.

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1. I am being told that the high-pressure fuel pump (hpfp) catastrophically seized and locked up internally while driving. Because the hpfp on the 3. 0l duramax (lm2) engine is directly driven by the engine's timing system, this sudden mechanical seizure instantly destroyed the engine timing gears and snapped/skipped the timing chain. The failed components are currently intact inside the vehicle and are fully available for inspection upon request at ron’s smith GMC in merced, CA. 2. The failure occurred on busy labor day (xxx) while our family of [xxx] was traveling back home at 70 mph on a major highway. The truck violently shook, instantly lost all engine power, and forced the vehicle into a dangerous limp-mode state before completely stalling in live highway traffic at night around 10:45 pm. This sudden loss of propulsion at high speed severely compromised our ability to safely navigate out of the way of fast-moving highway traffic, creating an immediate & extreme risk of a high-speed rear-end collision. At times hazard lights didn’t work causing family panic & screaming as truck shook with passing traffic. 3. The problem has been officially confirmed by ron smith GMC in merced, CA. Their service department diagnosed the issue, confirming that the high-pressure fuel pump had locked up and subsequently destroyed the timing belt/chain and engine gears. 4. The vehicle and its failed components have only been inspected by technicians at the ron smith GMC dealership service department. No police, insurance representatives, or outside third parties have inspected the vehicle yet. 5. I had been extremely happy with my truck and there were absolutely no warning lamps, dashboard messages, or driving symptoms prior to the failure. The truck was operating perfectly normally under cruise until the exact moment of the failure, at which point a "reduced engine power" warning flashed on the dashboard simultaneously with the mechanical lock-up, shaking, and immediate stall. Information redacted pursuant to the freedom of.

1. I am being told that the high-pressure fuel pump (hpfp) catastrophically seized and locked up internally while driving. Because the hpfp on the 3. 0l duramax (lm2) engine is directly driven by the engine's timing system, this sudden mechanical seizure instantly destroyed the engine timing gears and snapped/skipped the timing chain. The failed components are currently intact inside the vehicle and are fully available for inspection upon request at ron's smith GMC in merced, CA. 2. The failure occurred on busy labor day (xxx) while our family of [xxx] was traveling back home at 70 mph on a major highway. The truck violently shook, instantly lost all engine power, and forced the vehicle into a dangerous limp-mode state before completely stalling in live highway traffic at night around 10:45 pm. This sudden loss of propulsion at high speed severely compromised our ability to safely navigate out of the way of fast-moving highway traffic, creating an immediate & extreme risk of a high-speed rear-end collision. At times hazard lights didn't work causing family panic & screaming as truck shook with passing traffic. 3. The problem has been officially confirmed by ron smith GMC in merced, CA. Their service department diagnosed the issue, confirming that the high-pressure fuel pump had locked up and subsequently destroyed the timing belt/chain & engine gears. 4. The vehicle and its failed components have only been inspected by technicians at the ron smith GMC dealership service department. No police, insurance representatives, or outside third parties have inspected the vehicle yet. 5. I had been extremely happy with my truck and there were absolutely no warning lamps, dashboard messages, or driving symptoms prior to the failure. The truck was operating perfectly normally under cruise until the exact moment of the failure, at which point a "reduced engine power" warning flashed on the dashboard simultaneously with the mechanical lock-up, shaking, and immediate stall. Information redacted pursuant to the freedom of.

Lifters and camshaft failure, loud clanking, & sudden power loss on the 6. 2 motor are the first noticeable signs. Instantly when everything happened check engine light, cruise control, & stabilizer lights flashed. The sudden loss of power forced the vehicle to suddenly slow down forcing my camper into the truck. I was hauling a within weight standerd camper but had difficulty bringing both the truck with the camper to a safe stop. There were no early signs or signal prior to sudden cautostrophic engine failure & all service records have been completed by a gm certified service dealer.

I am the owner of a 2019 GMC Sierra 1500 4wd equipped with the 6. 2l l87 v8, VIN [xxx], currently at 177,271 miles. On [add date] while driving 40-45 mph westbound on [xxx] near xxx in [xxx], in a school zone, the engine suffered sudden catastrophic internal failure with complete loss of propulsion and would not restart. No prior warning lights or low oil pressure warning. Vehicle required tow from school zone. GMC dealer inspected and verified catastrophic internal failure. Dealer stated verbally failure is either camshaft broken in half or timing chain sprocket/pulley broken off or loose causing timing chain to come off. Timing cover was not removed to confirm. Dealer stated engine is not repairable and quoted $13,500 for new engine replacement only. I have copies of the work order and the dealer's written statement verifying internal failure and replacement recommendation. Engine and vehicle have been retained. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

See all problems of the 2019 GMC Sierra 1500 🔎.

Sudden loss of propulsion while driving on I-75 with cruise control engaged. Vehicle began to decelerate. Pulled off onto emergency lane. Engine was idle-ing roughly. Would not increase rev when gas pedal pressed. Shut down. Tried one restart. Unsuccessful.

Driving on I-75 with cruise control engages. Vehicle began decelerating. Pulled over onto emergency lane. Engine idled roughly. Shut down. Attempted one restart unsuccessfully.

My 2022 GMC sierra started hesitating two weeks ago between the speeds of 17-35 mph. It also hesitates going downhill. When I try to accelerate it hesitates causing a serious safety issue for me driving. I cant trust to move when I need to move across a busy intersection with semi tractor trailers coming at me. I can trust it to tow or haul anything anymore. This is well known and documented problem general motors has and the company deems it "normal operations" which is totally not normal.

Fuel filter and high pressure rail system the truck started shuddering and began to go into limp mode also shifted into neutral byitself no it was inspected by the dealership shop and now insurance check engine light came on and code p1089.

Purge pump failing confirmed at dealership this part has been recalled on same truck but not specifically this VIN . I was told I need to report it to you guys so that it could ge added.

Was traveling home and started losing power going up a hill on xxx. The truck was surging, the check engine light came on and an audible warning of no (low?) oil pressure. The truck shut off on a busy interstate highway and barely got onto the shoulder. The tow truck driver had to lay on the ground with part of his body in the lane of travel to place "skids" under the rear tires because there is no way to place this vehicle in neutral for a tow without a special gm tool. When I contacted harry robinson GMC service center in [xxx], they told me that it was no longer a safety recall because the truck had passed diagnostics and new, high viscosity oil was put in the truck xxx. The GMC app says code p0016 which is the dreaded 6. 2l camshaft to crankshaft alignment that accompanies engine component failure. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

13 unresolved problem codes relating to hard engine starting,rough engine running,vehicle initiating safe mode operation, upon a highway trip. P0016 engine code detected and onstar messaged for immediate service. No resolution at dealership , after resetting codes an additional 9 are active / pending at 2nd dealership visit. Abnormal engine operation since , dealership advises a hard failure has to occur before a resolution can be instituted. Similar advice from GMC direct phone call in help line.

I was driving on 96 w. In slow traffic on the freeway when the vehicle put itself in neutral and shut off.

I bought a new GMC Sierra 1500 denali with the 6. 2l v8 engine in December of 2025. 7 months later, I was driving home from work. When the car started, it sounded a little louder, but not out of the ordinary. I started driving and got a strange rattle when I was getting on the highway at around 65mph. I pulled off at the next exit and checked my fluids, checked under the car to see if anything was caught that was causing the rattle. All pressures and fluids were normal. I had onstar run a system diagnostic. The diagnostic read normal. I got back on the highway and drove about 20 miles at 75mph. The rattling continued. 20 miles later, the check engine light came on. I had onstar run a diagnostic and came back stating “engine and transmission system problem” with two error codes. One code said “an issue has been detected in the variable valve timing system adjust the timing of fuel delivery for more efficient engine operation”. The other code said “an issue has been detected in the ignition system which oversees the timing and spark necessary to ignite fuel in your engine” both error codes said to fix within one day. The GMC dealership was on the way home so I was going to stop there and see what they could do. I never made it to the dealer. About 2 minutes after the diagnostic, while doing 75mph on the highway, I hit the accelerator and the car did not speed up. The engine then shut off while I was in the left lane doing 75 mph. The electronics stayed on and the dash stated “press start to start engine. ” I pulled over to the side of the highway and put the car in park and attempted to restart the engine. The engine never turned over again. I could not get the engine to start. I could not shift the car to neutral to have it rolled up on to the tow truck. My truck was towed to the GMC dealership and they are now replacing the engine under warranty. Will upload any maintenance paperwork once engine is replaced.

While driving enroute to a concert in [xxx]. , in the passing lane on [xxx] around [xxx] & just before exit 22(mile marker 21) during rush hour on 7-23 at 5. 09pm, my truck abruptly lost power and shut off! it would not start, I could not engage "n" from "p" to attempt to push my truck to the far left side of the highway. This was a "very dangerous" situation as I could have been rear ended or much worse! I immediately called sos/on star for assistance. In the meantime, a police officer and state troopers showed up to divert the traffic around my truck. Eventually, a "hero" vehicle showed up and at the direction of the police, my truck was "dragged" from the passing lane to the emergency lane. As for getting a tow truck, 1 finally showed up after 5+ hours. I found out the you all have a contract with "aaa", which is the worse when it comes to getting any assistance. I was towed back to [xxx] to south town GMC dealership & arrived at 11. 25pm. It was only the next morning that I received an email from onstar dated 7-23 at 5. 07pm, with an "advance diagnostics" advising of a critical issue with the engine & transmission. The code was: p129f, which is the fuel pump and/or module. My truck now sits at the dealership with a dead battery, waiting for them to address. I have heard that there are issues and recalls in certain vehicles with this similar issue. I do have "extended warranty" protection thru ally that I bought. However, the shock is finding out that the only way to get it into "n" is a special dealer tool that goes into the transmission under my truck! are you serious??????? to have no ability to put my truck into "n" is not only unacceptable, but extremely dangerous. Especially with what happened to me & my family. At this point, I am at the mercy of my dealership to find the time to address this issue. Until then, I have no transportation & very upset with the stress of all that happened! information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b.

Corroded grounding strap failed cylinder 5 glow plug circuit cracked and separated exhaust backpressure valve.

I was driving on the highway when the vehicle started to make clinking noises. The vehicle started to lose power as I accelerated it would feel like something was pulling me in the opposite direction and the knocking noise would get louder. Ultimately, I had the vehicle towed to a dealership. This vehicle passed the l87 recall not too long ago, and the vehicle is barely used.

I was driving to work on 7/20/26 and my vehicle loss engine propulsion , engine failure and unable to restart vehicle and shift gears.

I own a 2023 GMC Sierra 1500 denali ultimate equipped with the 6. 2l l87 v8 engine. The vehicle previously experienced an engine failure that resulted in the complete replacement of the 6. 2l engine by an authorized GMC dealership. The replacement engine was installed at approximately 76,316 miles. After approximately 1,000 miles of driving with the replacement engine, at approximately 77,354 miles, the vehicle displayed a check-engine/service warning and experienced abnormal transmission shifting. I returned the vehicle to the GMC dealership for diagnosis. The dealer documented dtc p0747, identified as “transmission control solenoid valve 1 stuck on,” and recommended replacement of the transmission control valve body at a quoted cost of $2,665. 85 plus tax. The dealership has stated that this transmission condition is unrelated to the recent engine replacement. However, because the condition appeared only approximately 1,000 miles after a complete engine replacement, I have asked general motors to investigate whether the current failure could be associated with the previous engine failure, the engine replacement procedure, or other related vehicle systems. I have opened a case with general motors customer assistance and have deferred the customer-paid valve-body repair while gm reviews the matter. I am submitting this complaint so NHTSA/odi has a record that this vehicle experienced a major 6. 2l l87 engine failure requiring complete engine replacement and then, approximately 1,000 miles after that replacement, developed a check-engine warning, abnormal transmission operation, dtc p0747, and a condition requiring replacement of the transmission control valve body. I can provide the engine-replacement repair order, current diagnostic documentation, mileage records, dealer repair estimate, and gm case information upon request.

P1098 code indicating stuck/ unresponsive engine coolant control valve. N252508341 exists for this part; however claim is my VIN is not covered under the bulletin or included on any standard warranty coverage. Part should last more than 150k miles, vehicle less than 90k. Less than 2 weeks ago suffered a complete ebpv failure that destroyed coolant and def lines, also not covered. No explanation for why my specific VIN (a 3. 0l diesel in the supposedly covered my) is excluded. Have been unable to find evidence of any applicable vehicles that were 'covered' under this bulletin. Fault forces an unexpected derate which can engage while accelerating, including while merging into freeway traffic. This is an obvious safety hazard. Engine check light illuminates approximately 30 to 60 seconds before derate limits top speed and throttle response. No messages to operator. Dealer has confirmed issue.

Total engine power loss while driving 70mph on the highway in steady moving traffic causing a safety hazard, with 3 young children in the vehicle. No prior warning lamps, messages or symptoms to indicate a problem. Engine completely shut down while driving and will not turn back on. Had vehicle towed to the dealership. Certified GMC dealership did a full inspection and indicated that the engine assembly needs to be fully replaced. Nhtsa campaign 25v274 for vehicles 2021 and newer is for the same exact engine failure issue with the same engine size. I would appreciate you exploring the possibility of covering this catastrophic malfunction as an exception to the aforementioned recall campaign. Many other drivers have noted the same failure with the 2019 as was included in the recall for 21-24. Thank you for your consideration, please feel free to reach out to me directly to discuss further. I look forward to hearing from you!.

The engine went into limp mode as I made turn leaving the damn I was is in town and it was a lot of traffic could’ve been bad if I didn’t pull into the median left me devastated and no crank no start I’ve only had the truck a year it went down a month from when I purchased it.

The vehicle stopped dead in traffic and would not restart. No warning lights. This is a huge safety hazard. Had to be towed to a dealership. The dealership and other diesel shops said the issue is a known catastrophic cp4 fuel pump failure. The fuel pump shreds and metal shavings are found throughout the fuel system. Requires a full fuel system replacement. . . Quotes have been obtained from gm dealership and local diesel mechanics, ranged from $15,000-$17,000. There is a known fix and could have been solved by replacing the fuel pump with an alternative one, without putting us in a dangerous situation. There is also a settled class action lawsuit directly associated to this fuel pump and issue, however the vehicle was purchased in GA and therefore not included. Based on the VIN the truck would be included if sold within a qualifying state. Gm corporate and dealers know about this problem and the safety risk, but are not even suggesting the fuel pump conversation as a repair. They are putting customers in dangerous situations and leaving them with high bills.

See all problems of the 2016 GMC Sierra 1500 🔎.

The fuel pump control module went bad and the vehicle shut off while driving. The vehicle is only 3 years old. Everyone I know with a gm truck or SUV has had the same issue and the dealer service writer even told me they get at least 6 vehicles with the same issue per week. There is already a recall for gm SUV's for 2021-22 model years but not for anything else even though many other vehicles have the same issue. They replaced the module under warranty but it is all but guaranteed to just keep happening.

Gas fill door won’t stay closed.

See all problems of the 2020 GMC Sierra 1500 🔎.

While driving at highway speed, my 2025 GMC sierra suddenly began slowing down without warning and lost propulsion. When I pressed the accelerator, there was no acceleration response. The vehicle felt like it was braking or dragging instead of accelerating, creating a serious crash risk in traffic. A warning message appeared instructing me to “put in neutral and restart truck. ” I followed the instruction, but the vehicle would not restart. It sounded like it was attempting to start, but it would not start normally. A “service esc” warning also appeared. The vehicle was towed by aaa to a GMC dealership and remains available for inspection. The dealership provided a diagnostic trouble code report showing active codes: c2a07 engine control module indicated torque signal malfunction; u0101 lost communication with transmission control module; u0131 lost communication with power steering control module; u0140 lost communication with body control module; u0146 lost communication with central gateway module; u160f lost communication with brake system control module 1 on can bus 1; u1611 lost communication with engine control module on can bus 2; and u3003 battery voltage circuit voltage below threshold. The vehicle had approximately 22,000 miles at the time of the incident. The failure has not been repaired at the time of this complaint. The concern appears to involve a safety-related electrical, propulsion, powertrain, esc/brake, and module communication failure that caused sudden loss of propulsion, no acceleration response, warning messages, and a no-start condition.

See all problems of the 2025 GMC Sierra 1500 🔎.

While traveling at highway speed during rush hour commute, the vehicle lost engine power and stalled. While coasting, I tried to restart the engine several times without success. Before coming to a stop, I attempted to get to the shoulder safely. Unfortunately, a portion of the vehicle was left partially in the lane and on the shoulder. Once I was completely stopped, I tried to put the electronic shift control into neutral so I could push the vehicle safely to the shoulder. The shifter would not allow me to shift into neutral and other override methods researched failed to work. I continued to try and restart the vehicle without success. I was in an unsafe position during rush hour commute for about 50 minutes until roadside assistance arrived and loaded and towed the vehicle. There was no warning of the issue prior to the incident. A code (p129f-fuel pump driver control module speed signal incorrect) was produced after the stall occurred via my GMC app. My vehicle was towed to my local dealership for service, but have not received the vehicle back at the time of reporting.

While driving my vehicle, the engine and transmission lost power and the check engine light came on. The vehicle went into limp mode and engine propulsion was limited. Had I been traveling at a faster speed, this would have been very unsafe. After coming to a stop, placing the transmission in reverse did not move the vehicle and there was a grinding noise. I was able to savely move forward in limp mode, but the shifting was harsh. I was able to find an empty parking lot to safely park. The truck was towed to jim winter dealership in jackson mi for inspection.

1. The l87 engine loss of propulsion failed and is available for inspection at the service department at power swain Chevrolet dealership, fayetteville, nc. 2. I, other vehicles, cyclists, and pedestrians were at risk. That vehicle could have come down on the highway, causing a vehicle pileup, which could have caused mass casualties. 3. The problem is known; the service advisor informed me the vehicle's engine needed to be replaced. 4. There were absolutely zero warning lamps or my GMC app alerts to announce vehicle issues. I have attached the last two maintenance records I have on hand. I suspect the dealership will try to deny responsibility for repairs. An extended warranty most nearly means we expect it to break down and your safety is not our concern.

So I made an appointment to have my truck recalled and the Wednesday before I took it, and it cranked no start and I called the dealership. Ask if they had any other those like this and they said that it could be the fuel injector module and so I got it to a mechanic shop to read the codes and it gave me a code p062b and I asked the dealership to look into it and they never figured out what we were not wrong. I just testing the battery. Well, then I got it back after the recall was done and new transmission valve body put in and about 30 miles down the road it started to shake violently and had a flashing engine light so I got it home called the dealership the next morning because they were closed set up another appointment got it to the dealership dealership said it had a couple misfires but since it wasn’t over 100 they weren’t concerned even though I’m pretty sure it is related to the fuel model going out because it has been cranking rapidly whenever I try to start it, but they won’t do anything to figure out what’s wrong?.

I am submitting supplemental evidence regarding my 2021 GMC sierra (VIN [xxx]) for recall query rq26001, campaign 25v-274. Despite multiple repair attempts, my vehicle remains unsafe and non-compliant with gm service bulletin n252494002. The recall remedy was performed deficiently. [xxx] northeast Buick GMC installed a remanufactured short block instead of the required complete engine, reused the original seized-engine oil pan (which continues to leak), and failed to address critical electrical damage. Documentation proves they deleted labor operation 14buz (engine electrical) after their technician noted a blown mega fuse. A second dealer, penske Chevrolet, subsequently deleted labor operation 77cvz01 from my repair order, demonstrating a systemic pattern of ignoring recall-required repairs. Electrical damage has cascaded, resulting in a burnt fuse block and active faults p0615, p0617, p26e4, p26e6, u0623, and u0284. More critically, within 24 miles of my last service, the vehicle developed a new, severe safety failure: the "service brake pad monitor" system failed, accompanied by a red "service system" dashboard alert and a noticeably spongy brake pedal. These brakes were recently serviced, yet this failure introduces a new risk of crash not present prior to the recall "remedy. " gm executive resolution case xxx has provided no resolution, reimbursement, or safety assurance, ignoring all deadlines since xxx. I possess extensive documentation, including service orders showing deleted labor operations and diagnostic logs. I request this update be integrated into the investigation of rq26001, as the current remedy is demonstrably ineffective and has exacerbated safety hazards. The manufacturer’s refusal to remediate these issues, despite my compliance, leaves me with an unsafe vehicle and significant financial loss. I am prepared to provide all supporting records to substantiate this complaint. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).