IAC Stuck wide open
01-23-2016, 08:56 PM
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IAC Stuck wide open Hey guys!! So I'm still chasing issues with the car...I'm very close to just throwing a match down the fuel tank and calling it a day!! haha
So I'm having a idle issue...with the IAC hooked up the car idles at 3K rpm...Now if I unplug the IAC and set the plunger manually and do not plug in the IAC plug the car idles somewhat properly but low on power, shifts very very hard and throw codes randomly, and always different ones, I've gotten mass air flow, o2's, TPS, Map, Evap...But it seems the TPS code always stick around, atleast right now it is!
So with the old IAC and the key on, then off you can see the plunger move back and forth..ok...Now the new IAC dosent move at all with the key on then off...However if I set the plunger all the way out the car will pull it all the way back in...Not sure if they new IAC is maybe a dud?
I have replaced the TPS with 2 different sensors...BWD from Oreilly....the code is P1022 and P1002 P...Low voltage
I also bought a PCM from Hawks Third Gen thinking it was it...no go
Here's what's happening...Anytime the IAC plug is plugged into the IAC the car automatically pulls the plunger all the way in so that it's "wide open" thus causing my 3K rpm...it will not function properly with either IAC's...both of them pull the plunger all the way in and will not adjust it properly....
I drove the car 4hrs to Myrtle Beach tonight and it died 3 times...all around 70/75MPH...just died...alway cranked right back up...again IAC unplugged...plunger manually adjusted....
I had 4 codes when I got here...here they are:
p0107 Map sensor
p0122 TPS
p0131 O2's
p0452 Evap
I cleared codes and just like always the p0122 came back, and only that...with a brand new TPS sensor...I am at a loss right now, I'm not sure what to change, what to check anymore...no vacuum leaks, haven't found any ground or wire issues...YET...any help would be appreciated it!...This all started directly after a wrench sparked with the battery terminal!
So I'm having a idle issue...with the IAC hooked up the car idles at 3K rpm...Now if I unplug the IAC and set the plunger manually and do not plug in the IAC plug the car idles somewhat properly but low on power, shifts very very hard and throw codes randomly, and always different ones, I've gotten mass air flow, o2's, TPS, Map, Evap...But it seems the TPS code always stick around, atleast right now it is!
So with the old IAC and the key on, then off you can see the plunger move back and forth..ok...Now the new IAC dosent move at all with the key on then off...However if I set the plunger all the way out the car will pull it all the way back in...Not sure if they new IAC is maybe a dud?
I have replaced the TPS with 2 different sensors...BWD from Oreilly....the code is P1022 and P1002 P...Low voltage
I also bought a PCM from Hawks Third Gen thinking it was it...no go
Here's what's happening...Anytime the IAC plug is plugged into the IAC the car automatically pulls the plunger all the way in so that it's "wide open" thus causing my 3K rpm...it will not function properly with either IAC's...both of them pull the plunger all the way in and will not adjust it properly....
I drove the car 4hrs to Myrtle Beach tonight and it died 3 times...all around 70/75MPH...just died...alway cranked right back up...again IAC unplugged...plunger manually adjusted....
I had 4 codes when I got here...here they are:
p0107 Map sensor
p0122 TPS
p0131 O2's
p0452 Evap
I cleared codes and just like always the p0122 came back, and only that...with a brand new TPS sensor...I am at a loss right now, I'm not sure what to change, what to check anymore...no vacuum leaks, haven't found any ground or wire issues...YET...any help would be appreciated it!...This all started directly after a wrench sparked with the battery terminal!
01-23-2016, 10:58 PM
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I agree with that 100% It's like it's reading the throttle open at a certain percent/level when it really isn't...I'm sure it's something dumb! I have spent about $350 so far trying to fix this!...I don't have a scanner capable of doing any testing..I've got a $15 scanner just to check DTC codes and a multimeter...LOL...is this probably something that I will have to take the the dealer or even hawks thrid gen..I'm really trying to do everything I can to fix it and not have to take it anywhere because it costs lots of $$$ having others wrench on you car! ....I'm not against "investing" in new tools though...where might one get a good scanner capable of doing more in depth trouble shooting?
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01-24-2016, 09:07 AM
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Ok awesome! It looks like elm327 is the popular choice! Cant find any ones available locally, so I'll have to buy something online...I was hoping it was just a stupid sensor or some silly thing I could fix quick before leaving back home...the car is not running very swell right now. For some reason the car is slamming into Drive from Park, I mean it tries to lunge the car forward! And from 1st to 2nd it shifts very hard and goes above where it should in the rpm's to shift...shifts smooth after words, still not exactly perfect but it works.
Say the throttle is reporting somewhat open when it's really not...Then what? I mean I have replaced the TPS twice already...what would that indicate? The PCM would need to be tuned? Strange that this problem persists with 2 good working pcm's though...Am I the only one that hates issues like this?? lol
Say the throttle is reporting somewhat open when it's really not...Then what? I mean I have replaced the TPS twice already...what would that indicate? The PCM would need to be tuned? Strange that this problem persists with 2 good working pcm's though...Am I the only one that hates issues like this?? lol
01-24-2016, 09:43 AM
#9
What is elm327??
You're asking questions you already asked and already got some suggestions to troubleshoot.
A scanner will allow you to view the TPS in real time as the throttle is operated. I suspect a TPS circuit issue which means wiring problem.
You're asking questions you already asked and already got some suggestions to troubleshoot.
A scanner will allow you to view the TPS in real time as the throttle is operated. I suspect a TPS circuit issue which means wiring problem.
01-24-2016, 09:55 AM
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Elm 327 is a Bluetooth OBD scanner that you use your cell phone as the scanner with the help of a ap, like torque as mentioned above.
http://www.obdinnovations.com/elm327...nd-windows-pc/
The last part is what I was looking for from you guys...a wire issue...I understand I need the scanner to help in the trouble shooting process. I am going to go look over the wires and connections and see what I can find...if anything...I'm going to order a bluetooth/wifi scanner and when it gets here hopefully with the help from it and you guys we can get it fixed, and maybe I'll even learn a thing or two! Thanks for the help so far guys! It's much appreciated.
http://www.obdinnovations.com/elm327...nd-windows-pc/
The last part is what I was looking for from you guys...a wire issue...I understand I need the scanner to help in the trouble shooting process. I am going to go look over the wires and connections and see what I can find...if anything...I'm going to order a bluetooth/wifi scanner and when it gets here hopefully with the help from it and you guys we can get it fixed, and maybe I'll even learn a thing or two! Thanks for the help so far guys! It's much appreciated.
01-24-2016, 02:08 PM
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Well...this is going to be a embarrassing post...but I want anybody that comes across this thread to see what the solution to my problem was, so maybe it will help them...I believe I have fixed the issue with this car...We re-seated and tightened the PCM plugs back onto the PCM and that seemed to cure the car..no more check engine light and it idles, shifts, and generally runs pretty well...from a dead stop it seems to have plenty of power, going 40 and then to the floor it still dosen't have all of it's power, but the pcm might still be re-learning everything, we only drove about 15 miles just in town, havent gone on the interstate yet...
So the orginal problem was a bad PCM...Replaced with good used PCM...But failed to properly connect the 2 plugs...which caused these 2nd round of issues. ...New PCM, plugs properly seated and tightened seemed to have fixed problem. Thanks for all the help guys! I'm still buying to bluetooth scanner for future use! What a dumb mistake on my part the 2nd time!
So the orginal problem was a bad PCM...Replaced with good used PCM...But failed to properly connect the 2 plugs...which caused these 2nd round of issues. ...New PCM, plugs properly seated and tightened seemed to have fixed problem. Thanks for all the help guys! I'm still buying to bluetooth scanner for future use! What a dumb mistake on my part the 2nd time!
Last edited by johndeere 4255; 01-24-2016 at 09:38 PM.
01-28-2016, 12:59 PM
#14
I see you got rid of your edit. I'm assuming the problem is actually fixed then?
If you haven't done it already, there is a learn procedure that you have to do when you install a new TPS or it may not actually give you 100% throttle which might be what you're experiencing at 40 when you mash it.
If you haven't done it already, there is a learn procedure that you have to do when you install a new TPS or it may not actually give you 100% throttle which might be what you're experiencing at 40 when you mash it.