Deere7020 Posted June 2, 2013 Report Share Posted June 2, 2013 Wanted to update you guys on the car. Got injector and iac changed. Car is now running but idling at around 3000 rpms. Any ideas? Quote Link to comment Share on other sites More sharing options...
JimMadsen Posted June 2, 2013 Report Share Posted June 2, 2013 throttle position sensor maybe? when mine went it reved up in drive but at a stop. I think I had an error code though Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted June 2, 2013 Report Share Posted June 2, 2013 TPS, IAC, vacuum leak, throttle blade way out of adjustment, PCM learned bad minimum TPS value. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted June 2, 2013 Report Share Posted June 2, 2013 PCM learned bad minimum TPS value. my guess. pull the fuse and reset the computer. IAC is way out of position. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted June 2, 2013 Report Share Posted June 2, 2013 could be. seeing how he's dealing with a 91 3.4, assuming it's not a vacuum leak due to UIM/LIM gaskets, that would be the first(cheapest and easiest) place i would check. Quote Link to comment Share on other sites More sharing options...
Deere7020 Posted June 3, 2013 Author Report Share Posted June 3, 2013 Does pulling the fuse reset the computer? Would disconnecting the battery do the same thing? Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted June 3, 2013 Report Share Posted June 3, 2013 don't do that its way too much work. find the pcm fuse. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted June 3, 2013 Report Share Posted June 3, 2013 battery would do it, but it is a pain when it takes 5 seconds to pull the PCM fuse. underhood, on the driver's side strut tower, you'll find a little plastic box, inside is the fuel pump relay and the fuse for the PCM that retains learned memory. pull that fuse for ~30 seconds, then replace and the ECM will clear all learned values. there is another PCM fuse in-cabin, but it is only active when the ignition is in run or crank. if either fuse fails, the PCM won't turn on. Quote Link to comment Share on other sites More sharing options...
Deere7020 Posted June 4, 2013 Author Report Share Posted June 4, 2013 What do I do after resetting the computer. Do I just start the car normally? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted June 4, 2013 Report Share Posted June 4, 2013 yeah... give it some time to settle down after cranking, it will probably drive oddly for the first 5 or so drive cycles where the engine goes from ambient temps to ~180 or so. Quote Link to comment Share on other sites More sharing options...
Deere7020 Posted June 9, 2013 Author Report Share Posted June 9, 2013 Tried resetting computer. No help looks like I gotta change manifold gaskets and see what happens Quote Link to comment Share on other sites More sharing options...
pshojo Posted June 9, 2013 Report Share Posted June 9, 2013 THis is funny, I have similar issue with 3.4 After swapping out the intakes, i'm starting to experience high idle. Not at start up. It only occurs after i've driven it, then it idles 1200-2000 rpms. If I turn off the car and restart it will idle at 1000 rpms. I swapped out the intake and new LIM/UIM gaskets. I switched the TPS/IAC, but did not replace the Orings. Thoughts? Should I also try resetting the computer or does this sound more like warm vacuum leak? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted June 9, 2013 Report Share Posted June 9, 2013 (edited) that sounds like TPS.... that generally happens when you get off the throttle quickly, the TPS appears to overshoot the voltage drop and causes a bad minimum TPS value to be learned. at startup, a new value is learned. this exact situation happened with the MC. replaced TPS with a used ~03 impala 3400 unit, problem solved. you can confirm this if you're able to access scan data.... compare TPS voltage with a closed throttle immediately after startup and when the issue happens. compare TPS% afterwards as well. you'll likely find an identical voltage, but a couple of percent throttle in the after scenario. Edited June 9, 2013 by RobertISaar Quote Link to comment Share on other sites More sharing options...
pshojo Posted June 9, 2013 Report Share Posted June 9, 2013 Cool I'll try this when I get snap on scanner back from a friend. Saar, there are Sylvania bulbs that claim 40% brighter, I do know they run hotter. Would you use these in instrument cluster , or could this be too hot? Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted June 9, 2013 Report Share Posted June 9, 2013 exactly, why jump to any conclusions when you can just look at data? could be the coolant sensor or something. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted June 9, 2013 Report Share Posted June 9, 2013 if you've ever looked at the board on a cluster in a car that had any kind of never-ending bulb-on issue, ESPECIALLY GP UB3 clusters with the low fuel/coolant level/check guages issue, you'll notice the board discolors around those bulbs.... IMO: the factory bulbs are too hot, anything beyond that will risk damaging the board. Quote Link to comment Share on other sites More sharing options...
GM Guy Posted June 10, 2013 Report Share Posted June 10, 2013 I had a similar issue where the idle would be high and sometimes hit the rev limiter in park and then could turn off, start again and idle lower around 1200, and sometimes would be fine then touch the throttle and would go sky high. Ended up being a bad pressure sensor on the steering rack. Quote Link to comment Share on other sites More sharing options...
pshojo Posted June 10, 2013 Report Share Posted June 10, 2013 (edited) i definately do not like to throw parts at cars, Its amazing how much information you lose when you don't use it. Trying to remember what values are supposed to be when looking at scanner is difficult to remember some times, at least i still remember open/closed loop. I worked at Dodge dealership for a few years. The main things i did was head gaskets and timing belts on neons, recall work on stratus, and new vehicle preps because I was new guy and these didn't pay well. Didn't really get chance to work much with driveability. Edited June 10, 2013 by pshojo Quote Link to comment Share on other sites More sharing options...
pshojo Posted June 10, 2013 Report Share Posted June 10, 2013 Wow, i would've never guessed. Quote Link to comment Share on other sites More sharing options...
pshojo Posted June 10, 2013 Report Share Posted June 10, 2013 I did do a closer inspection on the board, the board was pretty brown around bulb areas. I bought LED's and called it good. Quote Link to comment Share on other sites More sharing options...
Garrett Powered Posted June 10, 2013 Report Share Posted June 10, 2013 few of the rusty gears in my head freed up just now and started turning. but there is a lot of TPS going bad out there. last night at work a pontiac 6000 or OLdsmobile looking thing with you could tell it was a 3.1 doing that idle search IAC too low thing and I thought to myself, why does life suck so bad with ethanol? just blame it on that if you want. but that's just the way it is. the led bulb thing is interesting. but would be giving off excess heat if the main engine ground was better? I have had a bunch of electronics fail with poor charging cars. is my thinking flawed? maybe it is not the bulb creating the strain on the circuit...could be dirty power? Quote Link to comment Share on other sites More sharing options...
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