My truck idles very rough when in gear, place it in neutral or park and idle is fine ?? I have checked for vac leaks, cleaned throttle body, Im thinking now possibly transmission mounts?? engine mounts are new. any one have any ideas
Idle issues
- Thread starter swerks
- Start date
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It may be doing something similar to the brake idle dip problem (Idle drops when you step on the brakes...) with the extra load when in gear... Where the solution is to actually turn the idle down..... ? But that's just a guess.... as I'm assuming you've turned the idle up? 
check the ignition system
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- #4
my idle is at 800 rpm , what should I check specifically with the ignition ??
check the spark plugs
check the spark plug wires. that means take em off look for corrosion
take off the distibutor cap. look for corrosion. look for carbon tracks
set the timing
make sure all 3 wires to the coil are tight
make sure when you tach it out, the coil or anything, for that matter, is not arcing out
check the spark plug wires. that means take em off look for corrosion
take off the distibutor cap. look for corrosion. look for carbon tracks
set the timing
make sure all 3 wires to the coil are tight
make sure when you tach it out, the coil or anything, for that matter, is not arcing out
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- #6
I was originaly thinking it was a vacume leak but I checked things out in that department as best I could. found nothing. new OME suspension. tranny is shifting fine. I still feel it may be a combo of vac leak and bad tranny mount. my mount is very cracked but I dont think it could cause my problem all on its own. I tried using propane to find leaks. ignition system checks out, Any other suggestions??????
get a vacuum gauge on there and measure what its pulling
coolant temp sensors can also cause this
coolant temp sensors can also cause this
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- #8
when I'm idling smooth I'm at 17-20,in hg when idling rough its at 12-14 in hg
ok so it sounds like you may have got a vacuum hose crossed with somthin. like when a vsv is switchin on
could be a leaking EGR valve but i doubt it
did you do some work to it recently you could have crossed somthing?
its like a switch is opening or somthing and leaning it out
check out the check valve for the brake booster also check the idle up switch on the PS, oh the PCV valve too
could be a leaking EGR valve but i doubt it
did you do some work to it recently you could have crossed somthing?
its like a switch is opening or somthing and leaning it out
check out the check valve for the brake booster also check the idle up switch on the PS, oh the PCV valve too
- Thread starter
- #10
thanks ill try to check those things out tomorrow. I did try to find leaks without success
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- #11
I fixed a vac leak and restored the factory air box, reset the ECU and now I have a much improved idle. not perfect but much better.
