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Rough Idel on ZC motor

2972 Views 4 Replies 3 Participants Last post by  Justdriving
My buddy David has a 88 zc
The idel keeps surging "only when completely warmed up" it surges between 1100 rpms and 1300 rpms
It runs great when it is cold. as soon as it kits middle of his temp gauge it starts.
I know the idel is high right now I am knocking it down for him when I go back out
Parts replaced so far
1. TPS
2. Head Gasket
3. temp sensor
4. burped lines radiator lines for air
5. replaced all vacum lines
6. replaced throttle body
7. replaced ecu from the teg to stock (no change)
8. Idel Air control valve
9. pcv valve and canister
Its not throwing any codes either<Can anyone help us with this ????
On the back of his Intake manifold there are 2 vacum line and we plugged both of those and it ran fine for a few days. They did just have a open line connected to each. Then all of a sudden it started doing it again. Does anyone have any ideas. Our last result is to take it to a honda mechanic at $75.00 an hour. Thats going to break his bank so any help would be greatful.
Don & David
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mine zc used to do that but not anymore.......i think in my car it just fixed itself or something. try messing with the idle screw on the throttle body. lower the idle and see wat happens.
see we did that and its weird it doesnt want to work. I have no clue what the heck is going on with it I am totally stumped.
did you replace the evac sensor yet. This will cause a shitty idle but will not always throw a code, because it is working fine just not as well as it can. I had to do mine. The two vacume lines on the back of the Intake manifold means it was an automatic ZC. Just plug them or you will have a vaccume leak. Plug them well.
hopeful answer

Every sensor got replaced I had an extra 90 block with all good sensors so we replaced them. Come to find out if you look in the integra manuel there is a section about adjusting the idel and on the zc motor you have to adjust it with the idel air control sensor disconnected and then turn the car off unplug the ecu (reset it) and then plug everything up and that should solve everything.
I havent tried this yet but someone from the resource.crx board figured it out.
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