Did replacing your ISV solve your low idle issues?
#1
Burning Brakes
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I'm pulling my intake and replacing all my vacuum lines soon. My car (85.5) runs great except it likes to dip down to about 750 RPMs at stoplights then grumble a bit. It corrects itself but is very annoying. If I run my AC it drops another 400 rpm. I'm not sure this is a sign of a faulty ISV...I've searched but have not found anything conclusive. It doesnt spike and stays consistent once it calibrates. Would replacing the alternator help stabilize the low RPM idle/ ac draw? It does this cold or warm...have new wire/plugs/cap/rotor/injectors.
Thanks
Thanks
Last edited by BlackOp; 06-17-2010 at 10:01 PM.
#2
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I'm having a similar issue with my 86, it has a rough low idle but drives just fine.
Car has new wire/plugs/cap/rotor/voltage regulator/vacuum hoses. I have another ISV to replace the current one. At that point should replace the old hoses associated with the ISV. Should anything else be considered while in there?
BlackOP when I replaced the voltage regulator it prevented dips while the ac was running.
Car has new wire/plugs/cap/rotor/voltage regulator/vacuum hoses. I have another ISV to replace the current one. At that point should replace the old hoses associated with the ISV. Should anything else be considered while in there?
BlackOP when I replaced the voltage regulator it prevented dips while the ac was running.
#3
Three Wheelin'
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I had all kinds of weird idle problems - but the worst was when I'd clutch at say 2500RPM and go into neutral...the idle would bomb out and sometimes the car would even die. I replaced both my ISV and my TPS with brand new units and haven't had any idle problems since.
It could be your idle screw though too - I've read that folks have had issues with theirs backing out or vacuum leaks in that area that cause idle issues.
It could be your idle screw though too - I've read that folks have had issues with theirs backing out or vacuum leaks in that area that cause idle issues.
#4
Burning Brakes
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I adjusted my idle screw today to just below 1000 and it runs perfect now. Idles @ 950 with the A/C on with no grumbles...perfectly smooth, like a new car.. Hurray....
#5
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I may look into the idle screw adjustment too.
Weird enough but since this rough idle issue I think the car is burning less gas.
Over the years a full tank would allow about 310 miles
With rough idle over the last couple months I get like 350 miles.
I am doing the same kind of driving and refilling when the needle is on E.
Does that make sense to anyone?
Weird enough but since this rough idle issue I think the car is burning less gas.
Over the years a full tank would allow about 310 miles
With rough idle over the last couple months I get like 350 miles.
I am doing the same kind of driving and refilling when the needle is on E.
Does that make sense to anyone?
#6
Burning Brakes
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#7
Wax On, Wax Off
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did you do it the Proper way by getting the engine completely up to operating temp, then disabling the ISV and adjusting it then? or did you just f*ck with the idle screw?
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#8
Burning Brakes
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did you do it the Proper way by getting the engine completely up to operating temp, then disabling the ISV and adjusting it then? or did you just f*ck with the idle screw?
Clark's Garage listed American 944's @ around 900 +/- 50. Mine was set too low. I may fiddle with it but the extra 40 isnt really discernible (to me). The shudder at every stop light is gone.
#9
Burning Brakes
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Just wanted to follow up...drove my car about 100 miles today, 1/3 being in bumper-to-bumper traffic. It drove perfect...I no longer hate my car. The end.
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#15
Burning Brakes
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I'm curious if this fixes your issue as well....sounds exactly what mine was doing...report back. I was going to replace my ISV, FPR, FPD, TPS , voltage regulator and vacuum lines. That's how fed up I was.....I have an O2 sensor I have to return now.