Running lean

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dkad260

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What is your vacuum at idle, using a physical gauge, also is the needle steady?

Have you done a leakdown test of the injectors? Verified fuel pressure?

Are the O2 sensors AC Delco or aftermarket?

Miles on plugs, are they AC Delco?

Just a few questions to help try to diagnose.
 
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builds4christ

builds4christ

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What is your vacuum at idle, using a physical gauge, also is the needle steady?

Have you done a leakdown test of the injectors? Verified fuel pressure?

Are the O2 sensors AC Delco or aftermarket?

Miles on plugs, are they AC Delco?

Just a few questions to help try to diagnose.
Hey DK.

I am unsure of the plugs (brand or mileage), but the 02 sensors are Walker. I have verified pressure at the rail to be steady at around 58 psi, if memory serves, but I have to look again. I checked fuel pressure and verified the number, but can't quite remember what the number was lol. There's no misfire history though.

I also have not check vacuum with a physical gage. That's a good idea. What should the vacuum be at idle?

I want to perform a leak down test, but haven't yet. I've never done one tbh.
 

dkad260

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What should the vacuum be at idle?

I don't know what these are supposed to pull, but I would assume 18-21 inHg.

Can you elaborate more on the history....how long have you owned it, and after you purchased it, what have you done to it and what if any problems were present at time of purchase and did the problems start before or after any service you performed.

Was it acting up when you bought it?

We definitely need to see what the PCM is seeing in regards to alcohol content. Could have alot of E85 in it and maybe it's not a flex vehicle.
 

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