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Weird Problems after Head Swap

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Old Nov 2, 2003 | 05:58 AM
  #1  
Nagash01WS6's Avatar
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Default Weird Problems after Head Swap

Alright...

I bent all zie intake valves just a bit... attemted to advance a cam and it didnt work out.

Anyway...

Since then... ive had a few odd problems.

1. P0121 - TPS Insufficient Activity and occasional P0172 and P0175.
2. Misfires. Very slight throttle... ~2000rpm no power at all, sounded like it was misfiring heavily. Let up, it would idle fine. Give it more throttle, it would stop doing it.

It did it another time yesterday. Was pulling out of the neighborhood... went to get on it... and it misfired like crazy. So I let out, gave it part throttle and it was fine. I would LOVE to have autotap on it when it does this.... but I never do. There was a DTC set... but as always... It went away before I could scan it.

Before it the good ol SES light comes on... it feels like its misfiring on a cylinder. You can feel it while driving, feels like a slight hesitation.

Anyone have any ideas??????
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Old Nov 2, 2003 | 11:41 AM
  #2  
Bowtieman4life's Avatar
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Check your MAP sensor in the back of the intake. It might be bent inside.

Originally Posted by Nagash01WS6
Alright...


I bent all zie intake valves just a bit... attemted to advance a cam and it didnt work out.

Anyway...

Since then... ive had a few odd problems.

1. P0121 - TPS Insufficient Activity and occasional P0172 and P0175.
2. Misfires. Very slight throttle... ~2000rpm no power at all, sounded like it was misfiring heavily. Let up, it would idle fine. Give it more throttle, it would stop doing it.

It did it another time yesterday. Was pulling out of the neighborhood... went to get on it... and it misfired like crazy. So I let out, gave it part throttle and it was fine. I would LOVE to have autotap on it when it does this.... but I never do. There was a DTC set... but as always... It went away before I could scan it.

Before it the good ol SES light comes on... it feels like its misfiring on a cylinder. You can feel it while driving, feels like a slight hesitation.

Anyone have any ideas??????
Reply
Old Nov 2, 2003 | 04:07 PM
  #3  
Nagash01WS6's Avatar
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Launching!
 
Joined: Jun 2002
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From: Orlando, FL
Default

Originally Posted by Bowtieman4life
Check your MAP sensor in the back of the intake. It might be bent inside.

hrm... interesting.

The MAP sensor was never forcefully touched or anything... but the wiring harness is kinda tight back there. I think I stuck the dipstick tube in front of it instead of behind the wiring harness. I gotta pull the trans and replace the flexplate, so that is an opportune time to take care of that.

Another question... what are normal MAP readings???? I assume I am getting them because its not throwing any codes other than the above mentioned... I could pick up another map sensor just to see what it does... and replace it when I do the trans. Im going to swap the TPS sensor out in a few days when I run out to Orlando.
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Old Nov 6, 2003 | 09:46 PM
  #4  
WILWAXU's Avatar
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From: League City, TX
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Moving to Internal Engine section.
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Old Dec 12, 2003 | 01:51 PM
  #5  
WicketMike's Avatar
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From: Killa Cali
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Originally Posted by Nagash01WS6
hrm... interesting.

The MAP sensor was never forcefully touched or anything... but the wiring harness is kinda tight back there. I think I stuck the dipstick tube in front of it instead of behind the wiring harness. I gotta pull the trans and replace the flexplate, so that is an opportune time to take care of that.

Another question... what are normal MAP readings???? I assume I am getting them because its not throwing any codes other than the above mentioned... I could pick up another map sensor just to see what it does... and replace it when I do the trans. Im going to swap the TPS sensor out in a few days when I run out to Orlando.

did you see anything wrong with your map sensor? did you find out what the problem was?
Reply




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