My Vue is Driving my mechanic nuts!

I have a 2002 Vue with an annoying “service engine soon” light problem. When I first took the car in to have it scanned, codes 171, 172 came up, which were “Fuel too lean Bank 1/Bank 2”. It also has a problem with a high idle condition where the idle will creep up to 2000 rpm when parked, and a vacuum leak. My mechanic fixed the vacuum leak and replaced the gaskets on the intake manifold plenum, reset the light, gave it back to me and within twenty miles the light came on again. He is left scratching his head as to what to do next as technical support for “old” Saturns is kinda non-exsistant after GM killed them off.



We got the car free after my father-in-law passed. It only has 20,000 miles on it, so I want to see if it can be fixed/saved.



Any help will be great. . .



GM Issued A TSB (Technical Service Bulletin For Their Technicians To Deal With “Service Engine Soon” And DTC PO171 (Fuel Trim System Lean Bank 1) And / Or PO174 (Fuel Trim System Lean Bank 2).

The bulletin covers 2002 only, Saturn Vues with V-6 (L81) engines.

Your mechanic was working in the right area. The 5 page bulletin outlines proper torque sequence and procedures for the sixteen intake manifold vacuum chamber bolts.

Insufficient or improper torque on these 16 bolts has created situations wherby the vacuum chamber can be lifted off its seals under deceleration and create an intermittent vacuum leak.

The bulletin also outlines checking the repair using a scan tool.

At any rate, you or your mechanic should get hold of the bulletin (#02-T-28). Have the mechanic read it and see if he thinks your vacuum chamber should be re-installed and re-torqued.

CSA

Sounds like you are having issues with your MAF sensor…at the very least take it out and clean it with an appropriate spray…Ironically I literally JUST finished fixing a P0171 on a Toyota Tacoma truck 15 minutes ago. I cleaned the MAF and it went away. The 171 is a system too lean…adn the 172 is a system too rich if memory serves correctly.

Try cleaning the MAF FIRST…many x this fixes it. If not it may be time for a new MAF sensor