87 wagoneer limited problem
#1
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Model: Cherokee
87 wagoneer limited problem
I have a 1987 jeep wagoneer limited with the 4.0l .
it runs smooth at idle and good at wide open throtle, but around 2000 rpms it spits, sputters, and backfires thru the exuast. I have done a compresin test, tune up, new tps, cam and crank sensors are new, new injectors, and cannot find a vacuum leak or intake leak.
anyone got a suggestion on what the problem is.
it runs smooth at idle and good at wide open throtle, but around 2000 rpms it spits, sputters, and backfires thru the exuast. I have done a compresin test, tune up, new tps, cam and crank sensors are new, new injectors, and cannot find a vacuum leak or intake leak.
anyone got a suggestion on what the problem is.
#2
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Year: 1997
Model: Grand Cherokee
Engine: 4.0
I'm gonna guess lack of fuel, so either a plugged fuel filter or weak fuel pump.
Have you been through Cruiser's tips?
http://cruiser54.com
Have you been through Cruiser's tips?
http://cruiser54.com
#3
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
I'm gonna guess lack of fuel, so either a plugged fuel filter or weak fuel pump.
Have you been through Cruiser's tips?
http://cruiser54.com
Have you been through Cruiser's tips?
http://cruiser54.com
How was the TPS adjusted?
#4
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Nick-b the fuel filter is new and checked the fuel pressure at the rail and that was fine also. Sorry forgot about them in the original post. I am new to this forum and did not know about cruisers tips, but I have been reading up on them today. Thanks for the info. This is my first jeep so I am learning as I go.
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#6
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At around 2,000 RPMs, at what load are you referring to? Tooling down the road casually, or heavy on the go pedal while running through 2,000?
#7
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sitting still or moving. at idle it's smooth and I can go straight to the floor with the pedal and it revs great but if I try to gradually increase the rpms or accelerating starting from still , once it gets to around 2000/2200 rpms it starts missing, sputtering, and backfires thru the exuast and then cuts of if I try to keep going. I can let off and go back to idle then push to the floor and it comes alive. It's just in mid throttle or gradual acceleration.
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#8
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I'm gonna guess lack of fuel, so either a plugged fuel filter or weak fuel pump.
Have you been through Cruiser's tips?
http://cruiser54.com
Have you been through Cruiser's tips?
http://cruiser54.com
#9
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
The TPS must be adjusted.
http://cruiser54.com/?p=54
But hell, Tips 1 through 5 need to be done also.
http://cruiser54.com/?p=54
But hell, Tips 1 through 5 need to be done also.
#10
Seasoned Member
I'm leaning against fuel flow/pressure issues. At WOT, the pressure is at it's highest, and you're not experiencing the issue at that point. If it were a fuel pressure issue, whether it be the pump, or the thermal vacuum switch that allows the regulator to reduce fuel return thus increasing pressure, I would agree. And, if you have no issues at WOT with full load, I also don't suspect the filter or pump.
Re-adjust the TPS carefully, and re-check the voltage after you tighten the last screw. Check the small hard plastic line that leaves the MAP and enters the rear left side of the throttle body.
Additionally, the only direct item that remains the same at idle and WOT is the EGR valve, which you're not experiencing the issue at these two throttle position events. And, you're not experiencing the issue with no load while you run unto and surpass the RPMs you indicated. In my mind I'm trying to rule out an EGR issue. Have you removed it, cleaned the seat, and installed with a new gasket?
Re-adjust the TPS carefully, and re-check the voltage after you tighten the last screw. Check the small hard plastic line that leaves the MAP and enters the rear left side of the throttle body.
Additionally, the only direct item that remains the same at idle and WOT is the EGR valve, which you're not experiencing the issue at these two throttle position events. And, you're not experiencing the issue with no load while you run unto and surpass the RPMs you indicated. In my mind I'm trying to rule out an EGR issue. Have you removed it, cleaned the seat, and installed with a new gasket?
#11
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
And, this problem can be caused by poor sensor grounds.
#13
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Year: 1990
Model: Cherokee (XJ)
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Back away from the keyboard and get busy on tips 1 through 5.
#15
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0