New comanche! Renix idle issues
#1
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Year: 1999
Model: Cherokee
Engine: 4.0 HO
New comanche! Renix idle issues
Bought me a manche for 700 the other day
Little background.. 88 4.0 auto 208k
Need to get it to pass smog
New:
Cap rotor plugs wires
o2 sensor
Cat
Muffler
Grounds scrubbed and cleaned
Tps adjusted
Tb and iac scrubbed.
Sprayed water around intake to check for a leak.. Nothing found
It idles high, kinda rough, and the idle will fluctuate every 20 seconds or so but only out of gear (park or neutral)
In gear it idles at 750 or so and still rough but no fluctuation.
I have noticed a slight hissing from the rear CCV valve line to the intake manifold. I took off the ccv hose and plugged it with my finger and it runs smooth as silk. Perfect idle in gear and park.
Did I find my cause? Or am I just wasting my time?
Crruuiiisssserrrrr!
Here's a pic of her... Oh ya D44 rear
Little background.. 88 4.0 auto 208k
Need to get it to pass smog
New:
Cap rotor plugs wires
o2 sensor
Cat
Muffler
Grounds scrubbed and cleaned
Tps adjusted
Tb and iac scrubbed.
Sprayed water around intake to check for a leak.. Nothing found
It idles high, kinda rough, and the idle will fluctuate every 20 seconds or so but only out of gear (park or neutral)
In gear it idles at 750 or so and still rough but no fluctuation.
I have noticed a slight hissing from the rear CCV valve line to the intake manifold. I took off the ccv hose and plugged it with my finger and it runs smooth as silk. Perfect idle in gear and park.
Did I find my cause? Or am I just wasting my time?
Crruuiiisssserrrrr!
Here's a pic of her... Oh ya D44 rear
Last edited by 831xj; 04-23-2014 at 10:12 PM.
#2
Herp Derp Jerp
Join Date: Nov 2011
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Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Sounds like a vacuum leak! I'd replace those fittings and lines. In his giant tips thread therr should be a P/N for the harness. Grab the CCV stuff too
#3
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Not wasting your time at all. Replace the front and rear CCV harnesses. Grommet is included with the rear one.
Have you cleaned the throttle body before adjusting the TPS on the engine side?
Done the sensor ground test?
I would do post 27 and eliminate the c101.
Can you still drive down the road to Greyhound Rock?
Boulder Burger still around?
Have you cleaned the throttle body before adjusting the TPS on the engine side?
Done the sensor ground test?
I would do post 27 and eliminate the c101.
Can you still drive down the road to Greyhound Rock?
Boulder Burger still around?
#4
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Year: 1999
Model: Cherokee
Engine: 4.0 HO
Hah! Ya that's actually pidgeon point in the pic. Picked it up in half moon bay!
I'll spend some time doing the c101 elimination and replace the rear ccv. Yes I removed the tps from the TB and cleaned the TB. Replaced it and I have it adjusted right on the money.
Why when I plug it up does it run perfect though?
I'll spend some time doing the c101 elimination and replace the rear ccv. Yes I removed the tps from the TB and cleaned the TB. Replaced it and I have it adjusted right on the money.
Why when I plug it up does it run perfect though?
#5
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Hah! Ya that's actually pidgeon point in the pic. Picked it up in half moon bay!
I'll spend some time doing the c101 elimination and replace the rear ccv. Yes I removed the tps from the TB and cleaned the TB. Replaced it and I have it adjusted right on the money.
Why when I plug it up does it run perfect though?
I'll spend some time doing the c101 elimination and replace the rear ccv. Yes I removed the tps from the TB and cleaned the TB. Replaced it and I have it adjusted right on the money.
Why when I plug it up does it run perfect though?
How's the hose MAP to TB?
#6
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Year: 90,84
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Engine: 4.0,2.5
[QUOTE=831xj;2840594]I have noticed a slight hissing from the rear CCV valve line to the intake manifold. I took off the ccv hose and plugged it with my finger and it runs smooth as silk. /QUOTE]
It's suppose to have a little 2.6mm orifice there in the CC valve. It actually even has moving parts to do things like block backfire gas and shut down at really high vacuum. Me, I'd try cleaning it....but it sounds funky in any case.
It's suppose to have a little 2.6mm orifice there in the CC valve. It actually even has moving parts to do things like block backfire gas and shut down at really high vacuum. Me, I'd try cleaning it....but it sounds funky in any case.
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#9
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Year: 1999
Model: Cherokee
Engine: 4.0 HO
Im unsure.. Im going to weld up my Exhaust manifold, put in a new NTK o2 and the PO had the new cat and muffler just clamped on so gonna weld those up too.
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