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  #1  
Old 05-24-2012, 10:41 PM
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Default Can Exhaust cause stalling?

I seem like the problem child these days...

My lower valve covers were leaking something aweful, so I pulled those and replaced the gaskets. Decided I would re-install the primary muffler to quiet the car down a bit from the primary bypass (since I'm not hitting the track this year) and now the car is acting funny. It starts and seems to run smoothly, but after a while of idling it stalls. Sometimes the warning lights come on and at one point I even had a clicking from the gauges in the dash after it stalled. Very strange.

The only change I made was adding the primary muffler back. I am running a Steve Wong chip, but am wondering if the muffler could be causing the issue? It has been stored in the basement for abotu 4 years. I can reinstall the bypass (it wasn't that bad for daily driving), but am wondering if I'm missing something else.

Thanks,

-Skip
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Old 05-25-2012, 12:07 AM
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yes, you are missing something. The track.
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Old 05-25-2012, 07:12 AM
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Sounds like a bad ground, is it possible that something was bumped while you were working on the valve covers?
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Old 05-25-2012, 08:00 AM
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Is the chip tuned specifically for the other exhaust you removed and not the primary exhaust? If so, there could be something Wong there (sorry, I just had to!).
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Old 05-25-2012, 08:09 AM
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..... racing with the Steve Wong chip




Quote:
Originally Posted by swftiii View Post
I seem like the problem child these days...

My lower valve covers were leaking something aweful, so I pulled those and replaced the gaskets. Decided I would re-install the primary muffler to quiet the car down a bit from the primary bypass (since I'm not hitting the track this year) and now the car is acting funny. It starts and seems to run smoothly, but after a while of idling it stalls. Sometimes the warning lights come on and at one point I even had a clicking from the gauges in the dash after it stalled. Very strange.

The only change I made was adding the primary muffler back. I am running a Steve Wong chip, but am wondering if the muffler could be causing the issue? It has been stored in the basement for abotu 4 years. I can reinstall the bypass (it wasn't that bad for daily driving), but am wondering if I'm missing something else.

Thanks,

-Skip
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Old 05-25-2012, 08:40 AM
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Thanks guys...I was tired and just wanted the car done yesterday...sometimes these things can be frustrating.

Yes the chip is for a primary or secondary bypass and LWF. So, I'm hoping that is the issue and guess I'll take the hour this afternoon (I'm going to leave the office early to button this up) and put the primary bypass back on. As I do that I'll look around and take a look at the wiring in the valve cover area, but don't thin there is anything in the lower valve cover area (I only worked on the lower covers since the uppers aren't leaking).

Antonio - I didn't race with the Wong chip, I installed it last summer b/c the car likes to stall due to the LWF when the A/C is running. Don't know if I'll be racing again for a while, taking a low key approach for a while.

-Skip
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Old 05-25-2012, 11:45 AM
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FWIW I have a Wong chip in my 86 that was optimized for a cat bypass pipe. I have not yet installed the bypass but my car runs just fine (thus the lack of urgency to replace the pipe and make the car louder).
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Old 05-25-2012, 08:19 PM
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Quote:
Originally Posted by swftiii View Post
Thanks guys...I was tired and just wanted the car done yesterday...sometimes these things can be frustrating.

Yes the chip is for a primary or secondary bypass and LWF. So, I'm hoping that is the issue and guess I'll take the hour this afternoon (I'm going to leave the office early to button this up) and put the primary bypass back on. As I do that I'll look around and take a look at the wiring in the valve cover area, but don't thin there is anything in the lower valve cover area (I only worked on the lower covers since the uppers aren't leaking).

Antonio - I didn't race with the Wong chip, I installed it last summer b/c the car likes to stall due to the LWF when the A/C is running. Don't know if I'll be racing again for a while, taking a low key approach for a while.

-Skip
A bad ground is an obvious choice.

It also sounds to me like the O2 sensors could be giving the ECU the wrong info, either because the chip is programmed to expect more airflow in the sensor behind the cat - or maybe the wiring on the sensors (or the sensors themselves) are loose?
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Old 05-26-2012, 07:10 AM
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Ignition coils were a problem back in the day (if it's a 964 like your picture). They would arc across the top of one or both coils causing missfires, a bunch of dash lights and stalling issues. You can pull the covers off the top of the coils and a lot of times see black trace marks where it's been arcing. Just throwing it out there.--Dave
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Old 05-26-2012, 11:59 AM
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Since I did a lower valve cover gasket swap I am betting I didn't seat the spark plug wires correctly, so am going to take it apart to do that and hope that fixes it. I checked for some arching and didnt see any anywhere.

Hope that is the problem.
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