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#1
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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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Skip '91 964 #54 '97 993 C4S |
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#2
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yes, you are missing something. The track.
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Clarke 68 912 75 911S Gemini Blue 3.0L 10 GT3 18 S6 22 F250 King Ranch Gone: 18 F250 King Ranch 12 F450 Lariat 11 GT3RS silver 11 GT3RS white 10 Cayenne GTS 08 Cayenne S 06 997 C4S cab (2) 05 997S C2 Launch 04 M3 Laguna Seca Blue 02 996 cab 91 964 C4 82 911 SC Euro 3.0 (3) 78 911 - 3.2 77 911 75 911S 73.5 911T 73 911T 72 911T 71 911T RSR vintage racer 3.0 69 911T Kermit vintage racer 2.0 68 911 Maximum Freedom, Minimum Government http://www.lp.org/ |
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#3
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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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Karl Lucky owner of a couple 911s 1963 LeMans Convertible 336 HO V8 with a manual 3 speed 1965 Honda Sport 50 |
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#4
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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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Everything has changed |
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#5
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..... racing with the Steve Wong chip Quote:
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2007 997 Turbo 1990 G Wagon Diesel 1990 Porsche 964 C2 G 1985 Citroen CX GTI 1988 Citroen BX GTI 1976 Vespa GTR 125cc 1970 Citroen Mehari 1968 Citroen ID 20 1965 356 C |
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#6
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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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Skip '91 964 #54 '97 993 C4S |
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#7
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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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Bob 04 GT3 86 Carrera 97 318ti "Guys, I'm coming in, I have too much grip." |
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#8
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Quote:
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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2001 Boxster "S", Some kind of Blue color (sold) 1986 Carrera, Guards Red 1998 Boxster, Guards Red ("amazing") (now amazingly broken) 1991 Audi 200 TQ20V with Stage II Boost kit (sold, alas) x2 Some other crap PCA Potomac Passed President 2015-FOREVER!!!!! PCA Potomac El Presidente 2013 (Chief Complaint Officer) PCA Potomac VEEP 2012 (President of Vice) PCA Potomac Drive & Dine Chair 2008-2011 |
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#9
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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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#10
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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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Skip '91 964 #54 '97 993 C4S |
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