GenVibe - Community for Pontiac Vibe Enthusiasts

So i'm changing the oil on my Buddy's 03 base vibe the other day, and i notice the CEL is lit up. Go get my scangauge & spare cable from my car, it comes up with a p0171, and p0420.

if i remember reading things right on here, the p0171 could just be a MAF in need of cleaning
and the p0420, could be a multitude of issues.
this car does have a small mystery coolant leak(doesn't appear to be getting into oil, nor is the car dripping anything on the ground, but he does have to keep an eye on the reservoir and top it off (it was low enough he didn't have heat last winter unless the car was moving, topped off the tank let the system burp, heat galore!) so it could be antifreeze fouling the cat....
Cat has no heat sheild
car is nearly 10yrs old, has 154k miles on it, and before he bought it(@120k summer 2010) it was in an obvious front end wreck, with "That'll do" repairs.
None of the gaps around the hood are consistent in their spacing, door checks broken on both front doors, drivers door scrapes against front fender every time you open/close it, fenders dont appear to be all the way down snug(can push down where they meet the a pillars) no front fender liners or splash guards, front pass door looks fine from the outside, but the brackets holding the window motor are all bent out of whack( if you open the window it goes of track, and getting to close properly is a 2 man job) and the suspension is shot on all 4 corners (he might have "blown" the struts himself though...)
oh yeah, it also has the infamous blend door tick, and the fan only works on high (we already replaced the resistor didn't work)

but back to those 2 codes, anything else in particular to look for?? (after i cleared the codes, the CEL came back on within 50 mi)

Regarding the codes, P0171 could just be the MAF, like you said. Clean it up and clear the code. As for P0420, ask him how tight he tightens the gas cap. He has to tighten it to two clicks for it to be properly sealed. If it's not, the code will show. It could be an o2 sensor (like on my friend's car) or, worse, the catalytic converter. Try the MAF and gas cap, and clear the codes. See if that works.

p0420 may end up being a sensor like kitt states. have you ran any other diagnostics on the car?

p0171 is a system too lean code. if he hasn't had the intake manifold gasket replaced, do so.

there is a tsb indicating faulty intake gasket leaking excessive air into the combustion chamber causing the lean issue.

the 420 could be directly related to the lean condition.

bluneon wrote:p0171 is a system too lean code. if he hasn't had the intake manifold gasket replaced, do so.

there is a tsb indicating faulty intake gasket leaking excessive air into the combustion chamber causing the lean issue.

the 420 could be directly related to the lean condition.

this is what my gut was feeling, but looking for confirmation. sorry about the rambling, just wanted to try and get across a sense of the over-all condition of the car.

oh, yeah, more recent issue that popped up, you can remove the key without turning the ignition back to lock. he's had the key out, in his hand, with the car still running.
anyone else??