Engine Codes after Grand AM Rebuild.

[zuki19]

Heres the deal, Just got my car together yesterday, we purged the coolant system, started it up... first thing i noticed, check engine, RPMs 500 over normal... 1500. I hooked laptop up to it and scanned dtcs, Multi-Misfires and PO507 Idle Control System RPM Higher Than Expected.

Car misses like crazy, on a quick run down the road i went to touch boost and Power enrichment, car felt flat on its face as soon as went to go into boost. and rpms dropped. as far as wideband is reading, A/F Ratio is good. 14.7 area on idle and cruise, 11.2 under boost... my main concern is it says its not overheating, but man my engine feels HOT the entire engine bay. I'm stomped for whats going on here... any ideas?

Car ran great even when I blew my headgasket and I didnt even drive it after i blew it... now it dont even want to run.

[ThePrimerSuspect]

sounds like a vacuum leak.

[zuki19]

Would that cause misfires also? and what can i do to check intake manifold leaks without tearing it apart?

[OMGz Turbo]

wow that sucks....i definitely wouldn't have touched boost if it isn't running 100% being that car isnt factory turbo'd but a vaccum leak could definitely hurt.

Do they use MAF/MAS?

[zuki19]

wow that sucks....i definitely wouldn't have touched boost if it isn't running 100% being that car isnt factory turbo'd but a vaccum leak could definitely hurt.

Do they use MAF/MAS?
well I couldnt even like hit boost, i could hear turbo but it wasnt making any boost... I was seeing if it was my new fuel pressure regulator to see how much it needed adjusted, but seems like its getting fuel. I didnt hook up my new fuel pump yet so thats not a issue.

yeah I have an LS6 MAF

[zuki19]

I can get a log on idle today, if any of you tuners want to take a look, im literally stumped. im gonna take bumper off today and redo my whole intake make sure everything is on there good

[SovXietday]

Yeah you've got a pretty considerable vacuum leak somewhere more than likely.

[zuki19]

Could it be my lower intake manifold? thats the only place i could think id have a vaccum leak unless a coupler is loose, ill check now. probably be back in an hour with an update, any suggestions are nice.

[SovXietday]

Could be ANYWHERE after the MAF.

[zuki19]

vaccum leak fixed, still runs like ass... its breaking up if i quick touch throttle to rev it up, idles fine, breaks up tho

[SovXietday]

What's everything that you changed? Your timing and everything is right correct?

I still think you have another leak somewhere that you haven't found yet.

[zuki19]

Car idles great now, runs good, has a boost leak out of back exhaust manifold, so boost isnt really there, but car gets really hot? Sounds like my water bump bearings are shot like my water pump is screaming... possibly reason why car is getting hot.

[rickhigginshtbr]

if your water pump's going it could be causing it... or you didn't burp the coolant fully and there's another air bubble somewhere.

[GmFwd]

Toss another set of coil packs on it and a different icm too and see what happens. Coilpacks are always acting up on the 3100/3400's.

Also, I don't mean to insult you, but are you 100% positive that your plug wires are on right? These engines WILL run decent with 2 of the right swapped. I did it myself once and was going nuts . Checked the wires, 2 were reversed.

[GmFwd]

Looks like you already got it fixed.

I have a spare waterpump you can have if you want. It has 15k miles on it

[ThePrimerSuspect]

Toss another set of coil packs on it and a different icm too and see what happens. Coilpacks are always acting up on the 3100/3400's.

Also, I don't mean to insult you, but are you 100% positive that your plug wires are on right? These engines WILL run decent with 2 of the right swapped. I did it myself once and was going nuts . Checked the wires, 2 were reversed.

true. my gtp did that. i thought the fuel pump was bad and it was just crossed wires.

[zuki19]

I think my fuel pump is like dead, i have a racetronix one that is ready to go in, just haven't got to it yet. as soon as i start to build up boost car breaks out and wideband starts getting lean.

[97TurboDSM]

my dsm did that around 10-12lbs when i was hard into the throttle. replaced the fuel pump and it was magically fixed.

[zuki19]

codes went away though, 507 randomly appears, not sure why... idle is steady.. and if 507 does show up, its idling at like 1500 rpms steady...

I still get a code for my Intake air temp... not sure why... i cant really tell if i rewired it right the second time because all the wires from my original wiring harness and ls 6 maf colors look different, they are faded.