Cat and muffler glow red
#1
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Location: grandville. mi
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Year: 2000
Model: Grand Cherokee
Engine: 4.0l I6
Cat and muffler glow red
I have a 98 jeep grand cherokee I6 stock exhaust and the cat and muffler glow red when you are going and the temp gauge reads 1/4 of the way. at that point the engine also starts to missfire and tries to stall. However if you let it idle it will run just fine all the way to temp. What could my problem be???? I have tried new cat, new muffler, new 02 sensors, new spark plugs, and new crank positioning sensor.
#4
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Year: 1993
Model: Grand Cherokee
Engine: 4.0
Are you dumping gas? Sounds like a vehicle that I had that had bad distributor caps and was dumping gas, killed the cats and fouled my O2 sensor our.
#5
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
Your cat converter is in melt down and clogging the exhaust, which causes the engine to run hotter while under load.
#6
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Year: 96
Model: Grand Cherokee
Engine: 4.0 I6
hope it helps
I had the same problem & symptoms recently. 96' gc I6. After a new cat, muffler & o2 sensor I traced it to a fouled out plug (#1) All 6 were new, but done before exaust repair. Its a cheap, easy check & or fix. Also cheap & easy is to make sure your firing order is correct & check your factory trouble codes. Autozone will check them for free if your check engine light is on & be able to pinpoint it alittle more. Good luck & keep us posted.
#7
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Year: 95
Model: Grand Cherokee
Engine: 4.0
x2 for misfires, a leaking injector can do it too. The thing is a rich condition doesn't cause the heat, but excessive fuel will destroy and then restrict a cat which then could cause the heat. A excessive lean condition will cause cause very high combustion temps and an exhaust system to glow but you should see it glowing the from manifold (possibly particular cylinder ports) and maybe some length of the tailpipe behind the manifold). If the exhaust was restricted to the point of causing the system to glow, you should also notice a loss of power on the top end, I have seen convertors restricted so bad the engine would barely run and even idle, even had a couple where it wouldn't even start (fouled plugs)
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#9
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Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
def sounds like raw unburned fuel is getting into the exhaust and heating every thing up ,is the exhaust tail pipe have a lot of black soot in it
#10
Old fart with a wrench
Sounds to me you've got a furnace in your cat! For whatever reason, raw gas is maintaining a flame in the convertor and will eventually melt the matrix and cause it to plug. Also, as the matrix fails, it will plug your muffler as well. Check out the source of you "over-rich" exhaust QUICKLY before it sets you vehicle on fire!
#12
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Year: 2000
Model: Grand Cherokee
Engine: 4.0l I6
Got a new cap and rotor and still glowing red, however it is not not glowing as red as it used to and its taking longer to glow red. This problem started when my brother got gas and sat in the meijer parking lot and then it started acting funny....the rpms were fluctuating a lot and then it would stall. We have run the jeep without the muffler back and the cat still glowed red. Thanks for the tips though, I really appreciate them!
#13
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Year: 1997
Model: Cherokee
Engine: 4.0L
It would be interesting to know what the ignition timing is running at when it's doing this. (A scan tool should be able to tell you this.) I know it's not adjustable and is controlled by a computer, but I can make the headers on a small block chevy glow nicely by retarding the timing significantly. The fuel burns out the exhaust rather than in the combustion chamber.
#14
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Year: 2000
Model: Grand Cherokee
Engine: 4.0l I6
That never crossed my mind till u said something that my timing might be off. Is there a way to regulate fuel pressure on a 98 gc? One of my buddies wants to do a fuel pressure test.......
#15
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Year: 95
Model: Grand Cherokee
Engine: 4.0
running pressure should be 49 PSI +/-5 PSI
leakdown pressure should not drop approx 10 PSI in 5 min
With your jeeps condition, if you have leakdown I would suspect an injector. Its pretty easy to remove the injector and rail assembly from the intake. I think you will only need to remove the cables at the throttle body and the cable bracket. You shouldn't even need to remove the fuel supply line, just swing/pivot the rail up on the fuel line connection. What I would do with the injector rail up and out is, turn the key to run and inspect the injector tips for leakage/spray.