Engine won't Idle
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From: Cape Coral, Florida
If you go WOT while watching your upstream O2’s they should go rich like 900 mv’s…if it goes low that signifies a bad or dirty MAF…another thing is to look at the MAP sensor with just the key ON…you should see about 14.7 psi at sea level with the scan tool.
Last edited by C5 Diag; May 27, 2023 at 08:51 PM.
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From: Cape Coral, Florida
Fred, I can remember years back one of the members had an Innova scan tool and he too had pages and pages of trouble codes so I don’t know if I would really trust that thing even the MAF and O2 readings you gave me…I’m not familiar with that product but how about using the cars “built in” code reader and see what you have stored there…I don’t know how old your scan tool is but I’d trade it in for something like an Autel or Launch scan tool…you HAVE to trust your equipment !!…maybe you can take a snap shot of those MAF and O2 readings ??
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From: Portland, Oregon
I did rescan and noticed that upon further review 98% of the 40 codes were Pending. I did take out the MAF and it was clean. I check the throttle body it was good too. I just took it out and for a drive without the MAF and it drove fabulous. only one code and that was a MAF code. I will order one any suggestion? I should confess this is a LS6 with a Vortech Supercharger with a water intercooler and Meth injection.
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You’d want to buy an OEM and new vs a reman…like I mentioned I’d look into how to view DTC’s on this Innova…you shouldn’t have all those pending DTC’s…you should check the reference ground on that MAF…with voltmeter you should see less than 100mv’s with the engine running MAF plugged in…good luck !!
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From: Cape Coral, Florida
The MAF ground is a body ground so you have to access that ground and clean it…I forgot it is a body ground and not a sensor ground which is a ground which goes to the PCM…if you have an incandescent 12 volt test light you can connect it to B+ and probe that black wire…should be bright…if you work on your car a test light is something you should have.
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From: Cape Coral, Florida
Did you ever post what the MAF reading is at “hot unloaded” idle ??…also look at your IAT after the engine is off for a few hours…it should be close to outside air temperature.
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From: Cape Coral, Florida
10.89 grams/second engine warmed up with no load ???…holy crap !!…MAF is over reporting !!…shouldn’t be more than 6.2 to 6.3…the PCM is thinking way more air is going into the engine so your injector pulse width will be too much !!…to much fuel !!…what does your MAP sensor reading at idle ??
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From: Cape Coral, Florida
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,509
Likes: 4,000
From: Cape Coral, Florida
Is this an aftermarket MAF ??…where did you buy it ??..any codes ??…a new MAF can be bad too…was the MAF ground checked ??
Last edited by C5 Diag; Jun 3, 2023 at 05:44 PM.