Seven problems related to tank assembly have been reported for the 1999 Mercury Cougar. The most recently reported issues are listed below.
I've got a repeatable failure that happens when I make a left turn or go up an incline while I have less than a quarter of a tank of gas in my vehicle. The car will lose power and start to stutter, and has completely stalled a couple times. I haven't had any parts replaced yet, but I found other people with this problem and an extended coverage program offered by the manufacturer that they say doesn't apply to my vehicle. This has also been NHTSA campaign id as well. According to the emails with customer service the program was for cars manufactured may 25, 1999 through November 30, 2001. My car was manufactured on may 24, 1999. I questioned if the one day difference in manufacture could actually exclude my vehicle, if my vehicle could actually be affected, and whether there was some way to tell if the affected part was installed in my vehicle (possibly by part number or serial number of the installed part). There are apparently at least several different parts (the pre extended program part, the bad part being replaced during the program, and the one replacing the bad part. I have requested but not been given a way to tell the difference between the different parts.
: the contact stated the vehicle hesitated, stalled, lost power and backfired when the fuel tank reached a level of three quarters to one half full. The vehicle restarted immediately after it stalled. The contact discovered NHTSA recall 04v421000, concerning the fuel system online. The VIN was not included in the recall.
I have had multiple problems since I purchased the car in 10/99. I have had the sun roof replaced once and now needs it again for the same reason; the track broke ($1000 to fix, $2000 if I go to the dealer). The ignition switch has been changed twice because it sticks (it need to be changed again). In 2/00 it started: whenever the car got cold, the car would either not turn on or would just shut down while I was driving. The car was brought to the dealer multiple times for the same problem. He changed numerous parts but was unable to resolve the issue, until a 2004 recall for something to do with the fuel system. About three years ago the engine light came on at which time the dealer replaced the catalytic converter. A few weeks later the engine light came on again at which time the dealer told me it was the head gasket. That, I had replaced by an independent mechanic and then still had to bring it back to the dealer to have the catalytic converter done a second time, and to have the computer reset to have the engine light shut off. Anytime I have work done on the car, even just maintenance, the check coolant light or the engine light comes on and I have to bring it to the dealer to have it shut off. In 9/05 the coolant light illuminated and a day later the engine light came on, I brought the car to an independent mechanic who changed the overflow tank because he believed it to be a bad sensor. After fixing that, the engine light would not go off as well as one of my brake lights. He did multiple tests and determined that it is something electrical, unfortunately he could not pinpoint the exact cause of the electrical problem. For some reason those lights have gone off but I expect them come back on soon.
When making a left hand turn and a half a tank of fuel or below, the engine misfires and almost stalls out, this presents a hazard when making a left-hand turn with oncoming traffic coming. The fuel system has been checked and seems to be operating fine.
No summary listed for above vehicle.
A seal around the gas tank swelled up so much that it broke, causing excessive amount of fuel to leak and spray everywhere. Fire department was called . Dealer replaced seal.
Plastic molded gas tank is disintegrating, causing vehicle to stall when driven at speeds between 60-70 mph. Vehicle has been bought back by manufacturer.