SES codes

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Aug 26, 2008 | 03:34 PM

Johns00Z28

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From: Germantown, MD

SES codes

My service engine soon light just came on the other day and I got the codes diagnosed and it read P0171 and P0174, system too lean on bank 1 and 2. Not sure what this means, can anyone help me figure it out?

Aug 26, 2008 | 03:50 PM

2001NBMZ28

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From: Jacksonville, FL

Could be a few things - I'd check for a vacuum leak first. www.gearchatter.com/viewtopic9039.php

Aug 26, 2008 | 03:59 PM

Johns00Z28

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From: Germantown, MD

Quote:

Originally Posted by 2001NBMZ28

Could be a few things - I'd check for a vacuum leak first. www.gearchatter.com/viewtopic9039.php

Where could the vacuum leak be coming from? Someone recommended I check the MAF and spray some carb cleaner on it in case some oil from the filter got in it.

Aug 28, 2008 | 07:17 PM

Johns00Z28

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Well I cleaned the MAF and checked and found the wingnut on my catch can wasn't tightnened so I tightened that. I pulled the pcm ign and pcm bat fuses to reset the pcm but to no avail. The SES light stayed on so I guess I'm going to have to take it by my mechanic to check for vacuum leaks.

Aug 28, 2008 | 09:34 PM

BAMALS1

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From: Rocket City

Have you checked the PCV Hose? That is a common place also right where it turns to go the intake under throttle body blade.

Aug 28, 2008 | 09:44 PM

Formula413

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You can check for vacuum leaks yourself, it's pretty easy. Just get a can of carb cleaner and spray it on and around any and all vacuum lines or anywhere there is vacuum. As someone mentioned, the PCV hose is a leading candidate, these seem to fail often on LS1s. The hoses to and from your catch can are another possibility.

Aug 29, 2008 | 02:34 PM

tording99Z28

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Quote:

Originally Posted by BAMALS1

Have you checked the PCV Hose? That is a common place also right where it turns to go the intake under throttle body blade.

I had this exact issue not 2 months ago and this is exactly where mine was. I just replaced that little angled piece with some 3/8" vacumn line with some hose clamps to make sure it stays secure and I have not had a problem since. Check here for sure.