94 z28 modded having issues with running crappy when warmed up
03-04-2015, 05:59 PM
#1
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94 z28 modded having issues with running crappy when warmed up
Ok guys my issue is when my car warms up it starts running rough but when given wot it acts like it clears up and hauls butt but as soon as I let it idle back down it starts running like crap again !!! Any ideas would be appreciated !
03-08-2015, 08:12 AM
#3
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Re: 94 z28 modded having issues with running crappy when warmed up
Well it has 150k+ but motor is rebuilt and about 80-100 miles on it so far and I tried to do the signature of it doesn't show up I'll reply again with mods and everything done to the car
94 z28 LE2 H/C package LT's 58mm TB 30# injectors 232/240-110 LS other then that is all minor stuff like new opti and new fuel pump an plugs/wires
94 z28 LE2 H/C package LT's 58mm TB 30# injectors 232/240-110 LS other then that is all minor stuff like new opti and new fuel pump an plugs/wires
Last edited by Bignasty85; 03-08-2015 at 08:16 AM. Reason: Signature didn't work
03-08-2015, 09:12 AM
#4
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Re: 94 z28 modded having issues with running crappy when warmed up
Who tuned it for the rebuild, LE2, etc? 30#/HR sounds small for the injectors, but that would only show up as a problem at WOT over 5,000 RPM, and you indicate it runs fine at WOT.
Sounds like a problem that happens when the PCM goes into closed loop, relying on the feedback from the O2 sensors to manage the A/F ratio. When you go WOT, the PCM once again ignores the O2 sensors. How old are the O2 sensors?
Have you scanned it for codes? Have you discussed the problem with the tuner?
Sounds like a problem that happens when the PCM goes into closed loop, relying on the feedback from the O2 sensors to manage the A/F ratio. When you go WOT, the PCM once again ignores the O2 sensors. How old are the O2 sensors?
Have you scanned it for codes? Have you discussed the problem with the tuner?
03-08-2015, 06:02 PM
#5
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Re: 94 z28 modded having issues with running crappy when warmed up
From what I have read on other people's problems it sound like O2 sensors but Jeff Creech from Carolina auto masters in Durham did the tune and yea it will run like straight garbage but if I give it WOT then it clears up so I'm leaning towards the o2's they aren't old but I can't remember how old might just have to stick some new ones in and try it !?!? Any suggestions on what brand to buy ??
03-08-2015, 06:05 PM
#6
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Re: 94 z28 modded having issues with running crappy when warmed up
I also did have it scanned for codes an injuneer said that it looked like some codes that got thrown bc of low voltage so I'm not sure if the codes are true or not ? The voltage meter looks to be in the right range when running and doesn't drop of I turn on running lights or the a/c
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