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Misfire Problems

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Old Feb 6, 2004 | 12:05 AM
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Default Misfire Problems - Something Shutting Down?

Alright... Ive been having this problem for the past few months and its driving me crazy and I NEED to fix it.

Problem... car acts like its misfiring. Absolutely no power.

This occurs at light throttle after a cold start when it reaches ~160 or after its been sitting for about an hour.

I currently have a P0121 stored in the computer (Insufficient TPS Activity).

We threw a scanner on today... and found that the drivers side O2 sensor is not oscillating at all... it tends to stick around 850mv, where as the passenger side goes from 0 to 900. It also feels like it is switching on and off.

Mods... they're in the sig.

And Ive swapped the heads as well... all three grounds are on one bolt.

Any ideas???????

Last edited by Nagash01WS6; Feb 6, 2004 at 08:32 AM.
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Old Feb 6, 2004 | 05:18 PM
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All grounds on one bolt = BAD

Split the the grounds up. I did the same thing on mine and had all kinds of odd electrical problems.

Sensors require a good ground. Dumping to much to the same source messes up the read voltage across the sensors.
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Old Feb 7, 2004 | 02:02 AM
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Will do then.

Did you put them all on their own ground on the head or did you have it as stock????
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Old Feb 7, 2004 | 02:18 PM
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I ended up putting them all on their own ground because I couldn't remember how the stock configuration was.
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Old Feb 8, 2004 | 10:49 PM
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Alright... I split them all into the stock config... and its doing... better. Now I only have to shut it off once when it starts doing it. Im wondering if maybe the passenger side coil packs are shutting down from oil and crap getting dumped on them... or maybe something else causing it... can anyone help me out???? Has anyone experienced this problem before????
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