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Old 07-13-2015, 02:48 PM   #1
V8RUMBL
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car not working, need help

so my car seems to have developed an issue. it will turn on and run for a very short time then it will just start cutting out. i can be driving down the road then as i go to accelerate, itll drop to idle. if i come back off the throttle, itll "catch" and continue on at whatever rpm its limiting itself to but as i pass its magical threshold, itll drop to idle again. this lists for about a minute or so before the car decides to shut down. and when i say "idle", its not the standard idle, its more like on the brink of dying idle... the right side turn indicator is also steady on while this is going on. im assuming something electrical, but if anyone has an idea, im all ears.
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Old 07-14-2015, 08:47 AM   #2
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more about this problem. it only happens once the car warms up. oddly, the longer the car is running from the cold start, the brighter the turn signal gets. once its been on long enough to start raising the temp gauge, it starts to miss and then shuts down after trying to rev it.
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Old 07-15-2015, 07:03 AM   #3
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Sounds like an IAC issue to me. So when you car is warming up, (open loop) it's getting a set of parameters to run from the ECU. These settings dictate all sorts of presets so that your EFI car can warm up properly. Once the car warms up and goes into closed loop, the car starts to get readings from the IAT, the MAF, the O2's, the TPS, etc. and it uses all these readings to control your IAC. So what's happening is the car runs fine cold, and then starts tripping out when it goes closed loop. You either have an ECU issue, or your IAC is on the fritz. I would try the simplest thing first and that would be to clean your IAC. If that doesn't fix it, test the IAC to see if 12 volts opens and closes the IAC. Hope this helps.
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Old 07-15-2015, 07:04 AM   #4
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Quote:
Originally Posted by 96gts4.6L View Post
Sounds like an IAC issue to me. So when you car is warming up, (open loop) it's getting a set of parameters to run from the ECU. These settings dictate all sorts of presets so that your EFI car can warm up properly. Once the car warms up and goes into closed loop, the car starts to get readings from the IAT, the MAF, the O2's, the TPS, etc. and it uses all these readings to control your IAC. So what's happening is the car runs fine cold, and then starts tripping out when it goes closed loop. You either have an ECU issue, or your IAC is on the fritz. I would try the simplest thing first and that would be to clean your IAC. If that doesn't fix it, test the IAC to see if 12 volts opens and closes the IAC. Hope this helps.
This makes sense. I'll try it
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Old 07-15-2015, 08:02 AM   #5
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So cleaning the iac worked. I can freaking believe this. My old mechanic told me he replaced it two months ago. Of course this was the same guy that told me my entire ac system was shot and needed replacing when i took it to a friend who discovered the belt tensioner was bad and not keeping the belt tight enough to turn the compressor. Amazing.
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Old 07-15-2015, 07:40 PM   #6
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Quote:
Originally Posted by V8RUMBL View Post
So cleaning the iac worked. I can freaking believe this. My old mechanic told me he replaced it two months ago. Of course this was the same guy that told me my entire ac system was shot and needed replacing when i took it to a friend who discovered the belt tensioner was bad and not keeping the belt tight enough to turn the compressor. Amazing.
Was going to say IAC... You need a new mechanic. My guy is a social "potato" ,but knows cars and works for cheap. Just sucks when he wants to hangout.
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Old 07-16-2015, 04:58 AM   #7
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Was going to say IAC... You need a new mechanic. My guy is a social "potato" ,but knows cars and works for cheap. Just sucks when he wants to hangout.
i actually got one. coworker used to work as a mechanic at toyota for years before he came on with us. i bitched to him about the a/c and he did the fix. he could have easily fvcked me. i already gave him all the cash to put in all the new a/c parts. he just fixed the belt issue and gave me back the rest of my money.
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Old 07-16-2015, 04:59 AM   #8
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also im still curious about the turn signal. wtf was up with that? obviously a symptom but still odd.
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Old 07-20-2015, 10:49 AM   #9
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Quote:
Originally Posted by V8RUMBL View Post
So cleaning the iac worked. I can freaking believe this. My old mechanic told me he replaced it two months ago. Of course this was the same guy that told me my entire ac system was shot and needed replacing when i took it to a friend who discovered the belt tensioner was bad and not keeping the belt tight enough to turn the compressor. Amazing.
I'm glad that worked for you. And yeah, I would make a lousy mechanic, not meaning that I wouldn't fix cars, I just would not and could not over charge people. I can't stand when someone says something is wrong with a car, and then they have like zero proof that the problem is what they say it is.

I'd say find a different mechanic, problem is you don't know which one is being truthful......
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