Cruise Control problems of the 2001 Mazda MPV

The consumer took his vehicle in for warranty work on the cruise control. The check engine light was on, so the dealer did a check and found the intake manifold was the problem. Consumer says that they recycled unused gas back through the intake to be burned, this caused carbon buildup. The dealer said that the carbon buildup was too bad and could not be cleaned, part had to be replaced. Consumer had two other mechanics look at the part and they said they would clean the part and then put it back on. The consumer said the part read Ford but the vehicle is a Mazda. Consumer says that problem is the recycled unused gas going back into the intake; the consumer says that this is a design flaw. The consumer had the dealer put the new part on, then the consumer stopped payment on the credit card used to pay for service. The consumer contacted the manufacturer and was told there was no recall on this part. Consumer was told by dealer the part was only good for approximately 60,000 miles then it would need to be replaced again. Dealer told consumer that if he cleaned the part, it would only last for 20,000 miles. Consumer says that he doesn't know if it is his fault or the dealerships fault for trying to sell more parts. Consumer has done research on carbon build up on the internet and has found that this is not the only intake with this problem. Consumer says that dealer told him that this is why Mazda uses a different motor now. Consumer says that vehicle had a little bit of cut out once in a while, but he doesn't think he can really tell any difference in with new the part.

When pulling off from a stop idle needle goes up to 3 rpms, and then drops to 1 rpm. There would be a loud metal to metal clinking noise when vehicle has shifted into reverse. Driver took vehicle to a mechanic, and mechanic stated that motor valves were bad. Please provide any further information.