P0171 and P0174

Z_ealot

Hey everyone, so to get to it as the title reads i have had 2 codes theown aince getting my transmission swapped out. Im thinking maybe i have an exhaust leak, but i took it back to the shop that did the work which was corner 3 garage and they couldnt detect any exhaust leaks. I have also noticed every so often i will get a slight lag between the time i hit the gas at around 3,000rpm and when the power actually reaches the tires. Also a few minutes after the codes came up the idle of the car went up to about 1100rpm and stayed there. I cleared the codes and the idle went back to normal, but the lag is still present. Just an fyi, the exhaust and air intake are completely stock

Trips

Hey Mike,

P171 usually a lean condition due to a vacuum leak.

That would explain the high idle and slow return to idle.

Try spraying some carb cleaner around the intake hose connections to see if the idle rises.

Have you checked to see if the plastic pvc baffle that attaches to the driver side intake is not broken or cracked?

If its stock? It's not uncommon for them to break as I've already gone thru two replacements.

That being fixed would take care of P174

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Z_ealot

That was my next stop after they told me they couldnt find any exhaust leaks, most of the plastics under the hood were in pretty bad shape when i picked the car up, but when i cleaned out the throttle bodies i didnt notice anything but that doesnt mean it wasnt there. Would that also cause the lag in acceleration?

Trips

I would guess the computers busy trying to compensate for vacuum leak and so it would affect throttle.

Carefully look at all the plastic intake pieces even if you have remove them for cracks or other damage that would cause the vacuum leak.

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Z_ealot

Makes sense to me since the problem seems to get worse the hotter that the engine gets...probably gonna pull the trigger on some z1 replacement silicone parts if it turns out to be a vacuum leak in the air intake hoses

Z_ealot

So was able to get in the engine bay after the rain and sprayed some carb cleaner around the pcv breather hoses and all the intake connections.....nothing happened. At this point im thinking the exhaust gaskets are giving out since I've had the mid pipe down off the car twice now and they kinda looked a little cruddy the first time i had the mid pipe down off the car. Picked up some exhaust gaskets today so i can take care of it this weekend. Interesting thing is since i cleared the codes i havent had them come back, but car still has a little bit of a lag when it's up to temp and i try to punch it every so often.

BeemaaZ

yup it's happening

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Z_ealot

Yeah, mine is nothing like that at all lol....holy crap dude, were you throwing codes at all?

BeemaaZ

RPM is at 1100 and it smells in the morning.

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Trips

Thats a pretty common break with aftermarket cai.

I suggest carefully removing it, and Krazy glue it, and order the Z1 silicone hoses.

Trying to find someone who has one in an emergency is pia.

I changed mine out after going thru a couple already.

Mine didn't break to the point that it started to affect the idle though.

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Z_ealot

Might also want to check and see if there's any exhaust leaks near the cats, i know greg from the corner 3 facebook group said they are a common failing point for exhaust leaks from the gaskets that go in between the cats and the mid pipe

Z_ealot

Well, got underneath the car and like i thought the exhaust was leaking. Had a couple points at the exhaust gaskets that were dripping water pretty good where they werent supposed to be. Got in there, installed new gaskets and put on some rtv sealant, just waiting for it to dry partially now and i think it should be good. Gonna keep an eye on it just in case, but i think we're good