oldman_tau
Well-known member
i have a vr4 but normal idle is going up and down intermittently, i suspect idle control valve but maybe you were able to encounter this problem..any hints? thanks in advance
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idle goes up and down intermittently
- Thread starter oldman_tau
- Start date
GSX_TC
Well-known member
I had that same problem till I sent my throttle body to Steve Monroe at throttlebodys.com and had it rebuilt and shipped back all for only 155, best 155 I ever spent.
So you sent your tb out and spent money before doing any testing? What if you got it back and you still had idle surge?
Oldman, do you have a multimeter? Use it to test the idle air control motor.
Quote:
2. ISC servo. Press down on the release lever of the wiring harness connector and pull it off the ISC servo. You may have to wiggle it a little as you pull. Do not pull on the wires. At this point you can test the resistance of the four coils or wait until you have the ISC servo off the throttle body. To perform this test, measure the resistance between terminals 2 and 1, between 2 and 3, between 5 and 4, and between 5 and 6. The resistance should be in the range of 28 to 33 ohms for the original and older models, and ~40 ohms for the most recent model, which is after our 3S cars were manufactured (see click The results for me were 30.1, 30.1, 30.3, and 30.4 (same order as given above) with the ISC servo off the throttle body.
click
If the iac tests fine then do a boost leak test. If you don't find any boost leaks in vacuum lines or ic piping/couplers then the problem could be your throttle body shaft seals are old and leaking, could be air is also getting past the biss screw rubber o-ring. If it still does it after getting the tb rebuilt and setting the biss then it may be the drivers in the ecu are bad.
Oldman, do you have a multimeter? Use it to test the idle air control motor.
Quote:
2. ISC servo. Press down on the release lever of the wiring harness connector and pull it off the ISC servo. You may have to wiggle it a little as you pull. Do not pull on the wires. At this point you can test the resistance of the four coils or wait until you have the ISC servo off the throttle body. To perform this test, measure the resistance between terminals 2 and 1, between 2 and 3, between 5 and 4, and between 5 and 6. The resistance should be in the range of 28 to 33 ohms for the original and older models, and ~40 ohms for the most recent model, which is after our 3S cars were manufactured (see click The results for me were 30.1, 30.1, 30.3, and 30.4 (same order as given above) with the ISC servo off the throttle body.
click
If the iac tests fine then do a boost leak test. If you don't find any boost leaks in vacuum lines or ic piping/couplers then the problem could be your throttle body shaft seals are old and leaking, could be air is also getting past the biss screw rubber o-ring. If it still does it after getting the tb rebuilt and setting the biss then it may be the drivers in the ecu are bad.
turbowop
Well-known member
The vfaq explaining all the different reasons for idle surge is pretty damn useful. No need to spend money on getting the TB rebuilt, other than for extreme cases. Last idle issue I had was due to a faulty idle switch. The one that is a single prong that closes with the throttle plate. Before that was a crappy FIAV. I fixed the idle switch by swapping in a good used one from another throttle body and blocked off the FIAV with some JBweld. Total cost of like $3. My car fires right up and idles fine even in below freezing temps and hold a rock sold idle while coasting, stopped, whatever. The key is learning what all the TB components and sensors do, which ones may be having issues or broke, and how to go about fixing them.
Mike could have fixed his idle issues himself and put the extra money towards adjustable camber arms for the rear of his car. /ubbthreads/images/graemlins/rofl.gif
Mike could have fixed his idle issues himself and put the extra money towards adjustable camber arms for the rear of his car. /ubbthreads/images/graemlins/rofl.gif
Last edited:
GSX_TC
Well-known member
Boy I wish I could throw some hot grease on your ass.
turbowop
Well-known member
Is that some kind of gay innuendo? /ubbthreads/images/graemlins/uhh.gif
oldman_tau
Well-known member
thanks guys for the tips, apprecited it. ill try and keep you updated.
DR1665
Well-known member
@OMT: I had similar problems recently. A quick fix is pulling the TB, separating the FIAV section, and installing a blank gasket cut from bulk gasket material. You'll want an impact driver for the screws, but it's a one hour job and then you just set idle with the BISS. No CEL and everything stays connected so the CARB monkeys leave you alone.
Good luck.
Good luck.
oldman_tau
Well-known member
thank you very much. i was able to fixed it..thanks!
