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Trouble after intake refresh

Old 03-19-2017, 02:21 PM
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Dannyfumi
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Angry Trouble after intake refresh

Happy Sunday all,

Just completed and intake refresh on a 86s3 32v, unfortunately the car is having a hard time starting, idling, or staying on.

Replaced the following:

- intake gaskets, - ISV, -TPS, -TPS harness, -rebuilt MAF, -spark plugs, -fuel injectors, -FPR, -vacuum hose kit, -all new hoses and elbow on throttle body, -temp 2 sensor, and CPS.

Any input greatly appreciated.

Dan
Old 03-19-2017, 02:34 PM
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huskeric
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sounds like a large vac leak...
Old 03-19-2017, 03:00 PM
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PorKen
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Make sure the throttle body idle screw is not turned all the way in CW (often happens if the intake had leaks before refresh). I found it best to have at least one full turn CCW to help out the idle control system.

Triple check the spark plug wires are routed properly to the correct cylinder.

Verify the MAF CO is at the initial adjustment of 382 ohms (may require less with a new MAF).
Old 03-19-2017, 03:01 PM
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docmirror
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Use the book procedure and test all the pins of the MAF. Check the wiring of the MAF harness. Since it's across all range, discount the ISV, plugs.

Test for vac leaks with a can of carb cleaner. Get it running, hold it steady at 1000 RPM, then spritz the carb cleaner around carefully. If the RPM goes up when you spritz, you have a vac leak at that location.

Use a 'noid light to check the pulses at each injector as the injector wiring harnesses have been moved around a lot recently.
Old 03-19-2017, 04:50 PM
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Dannyfumi
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Porken,

I have an x-pipe on, where do I measure CO2 levels? Where in the WSM are the procedures?

Thanks
Old 03-20-2017, 09:38 AM
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drscottsmith
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Double check your vacuum hose routings. On the L-jet cars, I know the different points of attachment on the throttle body are there because they either provide a constant level of vacuum regardless of throttle position or they vary (on purpose) with throttle position. I am not 100% sure your car will be the same but I would imagine so.

If you have the hoses connected to the wrong spots, it can cause major issues.

-scott
Old 03-20-2017, 11:30 AM
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SeanR
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From watching your video danny, start with the basics. Do you have spark or fuel? Need to know those before going further. From the vid it looks like your fuel pump is not running and that leads back to the CPS/CPS wiring. But you won't know for sure until the above is investigated.

This may not even be related to the intake refresh.
Old 03-23-2017, 10:07 PM
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SeanR
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Just to follow up. This ended up being one of the injector boots being folded over and the wires underneath frayed and touching each other.
Old 03-23-2017, 10:33 PM
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Thanks for posting the problem/solution!

Happy spring for O/P.
Old 03-24-2017, 01:13 PM
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docmirror
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Originally Posted by SeanR
Just to follow up. This ended up being one of the injector boots being folded over and the wires underneath frayed and touching each other.
Did you find it with a noid light first, and hunt down, or just moving stuff around?


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