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ErikShockey
June 23rd, 2007, 03:01 PM
Car: 2001 Camaro SS, full bolt-ons and Mti Z1 cam.

Story: i was taking a guy for a ride in my car, and he was going to buy it with cash in hand. i got on the freeway and punched it at about 20mph and let off at about 130ish. i then costed about a mile and exited. went through a few stop lights and then after the third stop the car started to idle and drive like it had a very big misfire. i pulled over and opened the hood and everything looked ok. i drove it back home (car was struggling to run, like it was running on 2 or 3 cylinders.)

i hooked it up to efi live and looked at the dashboard i noticed that the spark jumps everywhere and the manifold pressure was ~ 85kpa at idle. i thought it might be a vacuum leak, but i cant find one. i even tried plugging them and that didnt help either. the car idles at about 500rpm at idle and goes up to 800 or 900 in CL. still sounds like it has a huge misfire and runs like it. the car has no misfires though and will not throw any codes.

i have some screen shots and data logs and was hoping someone could help me this is my only car and i hate bumming rides everywhere.thanks alot Erik.

http://img2.putfile.com/thumb/6/16922271650.jpg (http://www.putfile.com/pic.php?img=5738632)
http://img2.putfile.com/thumb/6/16922271577.jpg (http://www.putfile.com/pic.php?img=5738631)
http://img2.putfile.com/thumb/6/16301511113.jpg (http://www.putfile.com/pic.php?img=5668335)

logs
Download Log_0000.efi (http://putstuff.putfile.com/90477/7479257)
Download Log_0001.efi (http://putstuff.putfile.com/90478/5771143)

joecar
June 23rd, 2007, 08:25 PM
Looking at logs, it looks like either an intake leak (manifold, tb, MAP sensor, PCV hose (oil cap?), vacuum hoses), or a broken MAP sensor.

ErikShockey
June 23rd, 2007, 08:42 PM
Looking at logs, it looks like either an intake leak (manifold, tb, MAP sensor, PCV hose (oil cap?), vacuum hoses), or a broken MAP sensor.

Well i replaced the intake gaskets, also replaced the map sensor, plugged up the pcv, and could not find any vacuum leaks. i am truely stumped on this one. i just dont know what else to try :frown: i am leaning towards something internal now. would any internal damage cause the manifold pressure to be so high?

joecar
June 24th, 2007, 03:30 AM
Erik,

You also checked the vacuum hoses/tubes (HVAC, brake booster, AIR solenoid, EVAP... i.e. anything that goes into the intake)...?

First check the easy stuff, might be a fault in the MAP wiring...

With key on engine off, usng the scantool:
- do you get any DTC's...?
- what does MAP read...?
- remove connector from MAP sensor, what does MAP read...?
- using a fused jumper wire, jumper the 2 pins in the MAP connector, if the fuse does not pop what does MAP read...?

Do you have a FAST intake...?

ErikShockey
June 24th, 2007, 08:37 AM
i dont have a fast intake, its an ls6. i will try to mess with the map sensor like you said and post up what happens. i have no dtc on the scantool at all. im going to go mess with it some more. thanks alot for giving me some tips.

ErikShockey
June 24th, 2007, 09:28 AM
ok with the car off the manifold pressure is 99kpa and unplugged with the car off its 10kpa. unplugged with the car on it just sits at zero. it did throw some codes, for the map sensor, p0107 but i guess that was due to being unplugged. before i started messing with it there was a stored code in the pcm p0506(low idle) but i suspect that is due to the car only idling at 3-500rpms.

ErikShockey
June 24th, 2007, 10:04 AM
also noticed when the car goes into CL it will hold a steady idle around 8-900rpm but when i take it out of park and put it in gear the idle drops to about 300 rpm. dont know if this help but i figured why not.

mr.prick
June 24th, 2007, 11:49 AM
what is your altitude?
85 kpa sounds kinda high for idle.

ErikShockey
June 24th, 2007, 01:12 PM
what is your altitude?
85 kpa sounds kinda high for idle.

not sure what my altitude is im in fort worth texas if that helps. but my kpa used to be no more than 50 at idle

mr.prick
June 24th, 2007, 03:11 PM
with key on motor off your kPa should be the same as your max kPa.
lower altitude seems to allow higher kPa readings,
that`s why i asked about altitude.
even if you had a leak that still seems like it`s high but maybe that`s what it is.
sometime a dirty MAF will make you run super rich and give you bad missfires
but i doubt that is what is wrong.

Chevy366
June 24th, 2007, 03:15 PM
Your about 600 feet above sea level , mine at the same altitude is 20 to 25 kPa .