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Sputtering/Hesitation problem...

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Old 04-30-2009, 08:12 PM
  #16  
knfeparty
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make sure the speed/ref sensors are attached well.

I had a really strange hesitation problem once and it turns out that it was caused by the alternator. My leads were so corroded that when I was driving with a heavy electrical load (lights and interior fans and/or engine cooling fans are the worst) it wouldn't have enough juice left over to make a good spark.

See if electrical load has any effect. If it does, check the alt. belt tension and consider cleaning the leads.
Old 04-30-2009, 10:37 PM
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VTCMart
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The plastic front for that Modis is not too much. You can get a 5-pack for about $43, Part #EAK0253L63A. That one looks pretty beat to hell.

See your local Snap-On tool truck...


Originally Posted by thewerxracing

Well, using my billion dollar Snap-On scanner, I realized every part that said Bosch on the damn car was in spec. Pumps, Coil, MAF, fuel injectors. Everything. So I went back to basics...
Old 04-30-2009, 10:53 PM
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Ditto on the grounds, speed and refrerence sensors. I would add the TPS to the list.

I had the same problem, only happened in right hand turns...finally solved by replacing a J-boot that was leaking in un-metered air.
Old 05-01-2009, 12:15 AM
  #19  
thewerxracing
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I was thinking the same thing about the alternator. I am running a lightweight relocation bracket on it and the wrong size belt. Anyone have any idea what the right size would be for an alternator relocation bracket? Its only a small problem, but since we're discussing it....

Im going to have to crack open the bottom of the tank to poke around. JOHN AZ- is that what it looks like if I were to unscrew that nozzle on the bottom of the tank? it looks like it has a hex on it to accept a wrench. Does it just screw out?
Old 05-01-2009, 12:21 AM
  #20  
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Originally Posted by VTCMart
The plastic front for that Modis is not too much. You can get a 5-pack for about $43, Part #EAK0253L63A. That one looks pretty beat to hell.

See your local Snap-On tool truck...
Hahah! Sounds like you know your tools. Are you a snap on truck owner?
Old 05-01-2009, 09:36 AM
  #21  
VTCMart
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Originally Posted by thewerxracing
Hahah! Sounds like you know your tools. Are you a snap on truck owner?
Diagnostics Sales Developer for the truck guys. I have about 40 trucks in my territory.
Old 05-01-2009, 11:09 AM
  #22  
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Originally Posted by VTCMart
Diagnostics Sales Developer for the truck guys. I have about 40 trucks in my territory.
I thought those were OBDII scanners/dataloggers/reprogrammers/kitchen sink whatever, but limited to things with computer interfaces.

They can do things useful on these cars too? (please tell me no, and tell me that they are complete trash. They are too expensive for me to want one).
Old 05-01-2009, 07:40 PM
  #23  
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There are a lot more features for OBD-I and OBD-II vehicles but the 4-channel lab scope, DVOM, and digital pressure transducers can come in handy on any vehicle. You can record scope waveforms to the internal memory or a CF card for later review to catch intermittent glitches.

Originally Posted by DarylJ
I thought those were OBDII scanners/dataloggers/reprogrammers/kitchen sink whatever, but limited to things with computer interfaces.

They can do things useful on these cars too? (please tell me no, and tell me that they are complete trash. They are too expensive for me to want one).
Old 05-02-2009, 01:20 AM
  #24  
944Ross
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Here's how I solved the same tank screen problem (after ruining a brand new pump with ingested sand). Mr. Gasket (first name in Porsche parts!) sells a chrome fuel filter with 1/2" connections for $12 (Summit P/N MRG-2526). I put it in the line from the tank to the pump, and don't rely on the internal tank screen. The MrG part is made to flow a huge amount of gas, it's for big-block drag racers. Did I mention it's only $12, vs $40 freakin' bucks for the OEM screen? Got mine from Summit Racing.

But honestly, you're pumping oil on #1 cylinder, I think you've got other problems, most likely rings.
Old 05-02-2009, 05:11 PM
  #25  
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944Ross- It hasnt come back... yet. The new plugs and surrounding areas look good. Hmm.

Anyway- Thanks for everyones help! I discarded the old in-tank filter and left it out. Then I threw on an in-line filter from a 199X Chevrolet. (Fram Part #XXX (Not sure yet)). I put it in before the pump. The car runs healthier than ever! Thanks again!
Old 05-03-2009, 11:41 AM
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Originally Posted by VTCMart
You can record scope waveforms to the internal memory or a CF card for later review to catch intermittent glitches.
Mmmmmmm. Portable data logging scope.

Damn you, I said make me NOT want one.
Old 05-04-2009, 10:12 PM
  #27  
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944Ross- I took a similar approach.






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