Check Engine codes after mods install

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Welfare

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I just installed a 2.6 pulley, tensioner, CAI, thermostat, plugs, and tune. The check engine light came on and is throwing P0171 and P0174 (running lean) and there is that slight smell of it running lean in the garage when it idles. Took it out for a short around the block for a short casual drive and car seemed fine. Is this most likely a tune issue?

Also noticed when I turn the car off there is the sound of almost a slight air leak coming from the passenger side near the thermostat/coil cover area. After a couple attempts can not seem to find the source and it's just a slight little whistle. Is this normal after shutoff?

Any help will be appreciated!
 
Zemedici

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Seems like 02 codes.

Check the intake to make sure its nice and tight with no air leaks.
 
nxhappy

nxhappy

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could be a vac lean. check all connections.

could also be the MAF sensor. Did you install it the correct direction ?
 
SCGallo2

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Did you get those codes and check engine light during the first start-up and idle after installing your parts and loading your tune? Or did you get them while you were road testing the car?

I have seen those with my current tune during a run at the strip where I was WOT in 4th gear through the finish line, then pushed the clutch in and shifted to neutral while braking for the turnout... WOT straight to idle at 130mph basically. Check engine light came on. Went to the pits and checked for codes, came up with P0171 and P0174. Cleared them and made another run while datalogging, and I shifted to fifth after the finish line and let the engine wind down while braking that time. Never saw the check engine light or codes again. Sent the datalog to my tuner and let him know about the codes. His reply was he could believe that I saw them during decel, since my car would not throw those codes during WOT, but everything looked fine in the datalog. He also stated that if I cleared them and they stayed gone, all is well. In the end, we both agreed that they were probably self-induced by my technique on that run. Never saw the codes again, even after multiple runs down the strip.
 
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The codes came up after first start up and idle. I cleared them after changing the plugs again (some were not gapped correctly) thinking it was that. Started it up and daily drove around a few local blocks, nothing at all running WOT just a short 1/2 throttle pull in second and later noticed the light had come on. Plugged in the tuner and it's still throwing the same codes.
 
SCGallo2

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Ok, sounds like you have a more serious problem than I experienced. I would not drive the car until you resolve the issue.

Take a look at your fuel rail pressure and temp sensor located on top of your passenger side fuel rail. It has a small plastic vacuum/boost line that runs from the sensor to the intake manifold just below your supercharger. Make sure that it is connected on both ends and not broken anywhere. That could cause the whistle you are hearing and the lean condition. If not that, recheck all connections on your CAI.

vac_boost line1.jpg

vac_boost line2.jpg
 
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Nsssane1

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Make sure Cai is on T/b correctly no air leaks look under the t/b make sure its on good, Id think tune related if all the connections are ok.
 
SCGallo2

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From the pics you posted, your MAF sensor mount on the intake tube does not appear to be sitting flush. Can you confirm there is a good seal there against the tube?

Chances are unmetered air is being drawn into the engine. More than likely, something did not get re-connected properly or was damaged when installing your mods. If you cannot find anything out of place, contact your tuner for assistance.
 
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What is a good way to efficiently test that for a leak? That area of the bay has a lot of residual wind from the belts/pulleys.
 
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Turned out to be the tune was the issue, also why the boost gauge wasn't working. Just updating, I've seen other's with the same issue and if they find this thread and are having the same codes/issues contact your tuner. Thanks for the support
 

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