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Engine wants to try to die above 40mph Help!

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Old Dec 12, 2010 | 07:07 AM
  #16  
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Originally Posted by randman
I'm no genius, but that just don't seem normal..LMAO

would placing a piece of paper over the pipe do the same thing?
i hope you guys are smart enough not to grab the damb tail pipe hello?
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Old Dec 12, 2010 | 07:10 AM
  #17  
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the whole idea here is the exhaust pressure when reving the motor will make you hand get pushed awa from the pipe
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Old Dec 12, 2010 | 08:57 AM
  #18  
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Originally Posted by BlackXJ
Leave your cat alone, its not clogged. Change the fuel filter, and enjoy your XJ again.
The fuel filter on a 99 is part of the fuel pump assembly, which is located inside of the gas tank; tank has to come down to replace.

It is not replaced until symptoms/testing point directly to it.

That is why I recommended testing of both fuel delivery and for exhaust restriction. Hunches and guesses generally leave you with less money in your pocket and still symptomatic.

It could be something entirely different, but in my garage, those two things would be the absolute first things I rule in or out, with tests that can help you isolate the root cause.
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Old Dec 12, 2010 | 11:29 AM
  #19  
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Originally Posted by freegdr
i hope you guys are smart enough not to grab the damb tail pipe hello?
Hello!
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Old Dec 12, 2010 | 11:33 AM
  #20  
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Originally Posted by tjwalker
The fuel filter on a 99 is part of the fuel pump assembly, which is located inside of the gas tank; tank has to come down to replace.

It is not replaced until symptoms/testing point directly to it.

That is why I recommended testing of both fuel delivery and for exhaust restriction. Hunches and guesses generally leave you with less money in your pocket and still symptomatic.

It could be something entirely different, but in my garage, those two things would be the absolute first things I rule in or out, with tests that can help you isolate the root cause.
I subscribe to the theory of Fact, most of the time.. I also like to keep the duckets in my pocket.. Shelling them out unneccassarily is not my idea of a good time!
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Old Dec 12, 2010 | 12:25 PM
  #21  
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So I cranked it up, put a piece of paper in front of the tail pipe (touching) the exhaust pushed it away at idle...reved, it was a a steady stream of air, keeping the paper pushed away...little bit of white exhaust, but it is fairly cold here today..

Pulled the air filter cover and the filter is fine... seems like a good amount of black stuff inside the hose that goes from the filter housing to the manifold...

How would i check the fuel delivery?
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Old Dec 12, 2010 | 12:31 PM
  #22  
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if it was the Cat wouldnt it do the same thing in neutral while revving to 3k?
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Old Dec 12, 2010 | 12:36 PM
  #23  
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Originally Posted by xPlover24x
if it was the Cat wouldnt it do the same thing in neutral while revving to 3k?
was I supposed to put it in Neutral and then rev?

And by do the same thing, do you mean as when it was being driven?
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Old Dec 12, 2010 | 01:07 PM
  #24  
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Put it in Neutral and reved it, with paper at the pipe...same thing as when it was in park...steady stream...

of course there is not an rpm guage, so just had to guess at 3k rpms...
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Old Dec 12, 2010 | 01:43 PM
  #25  
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If the problem is fuel delivery problem, it will go lean - usually causing bucking or spitting when this happens. If the problem is clogged cat, it will go rich.
I had similar problem, had computer hooked up to see O2 sensor signal while driving. I confirmed clogged cat by removing the (upstream) O2 sensor and going for a drive. When I stepped on the gas, it sounded like a jet taking off, or a compressed air hose running full blast.
New cat = runs great now.
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Old Dec 12, 2010 | 04:12 PM
  #26  
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So, if the problem turns out to be the Cat... Can I just get one of these and replace it? http://www.autopartswarehouse.com/de...1&apwidzU9j4QV

is it that simple? Not that I want to spend money on this when I really need a roof basket..LOL...
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Old Dec 12, 2010 | 04:42 PM
  #27  
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cut the old one out, your prob not planning on welding so bolt it back on with u bolts, or better yet, hit up the exhaust shop or a welding shop and have them weld it on. If you dont get it on right and leak before the cat, your problems will remain or increase
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Old Dec 12, 2010 | 05:00 PM
  #28  
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If we cut it out, and just clamp a piece of str8 pipe in there until we can get a hold of the cat, would that work for a couple of weeks?
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Old Dec 12, 2010 | 05:03 PM
  #29  
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if the cat was plugged the exhaust would of not gotten stronger when reving check fuel pressure would be my next step
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Old Dec 12, 2010 | 05:05 PM
  #30  
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If the cats actually clogged than yes. Its not legal though, and IDK if your year has 02 sensors after the cat..probably not unless you live in CA
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