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New comanche! Renix idle issues

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Old 04-23-2014, 10:06 PM
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Default 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
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Last edited by 831xj; 04-23-2014 at 10:12 PM.
Old 04-24-2014, 06:30 AM
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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
Old 04-24-2014, 07:16 AM
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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?
Old 04-24-2014, 08:46 AM
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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?
Old 04-24-2014, 09:00 AM
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Originally Posted by 831xj
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?
Because it's getting too much air? From someplace else?

How's the hose MAP to TB?
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Old 04-24-2014, 02:24 PM
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[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.
Old 04-24-2014, 02:52 PM
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Pick n pull.. $2

Gonna slap it on later. Stupid autozone and napa can't find it in their system
Old 04-24-2014, 03:30 PM
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What brand 02 sensor?
Old 04-25-2014, 05:18 PM
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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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