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Car wont idle? MAF sensor? Whats your TPI idle at?

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Old 08-09-2008, 09:20 PM
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Car wont idle? MAF sensor? Whats your TPI idle at?

Ok I have just a 305 TPI. Someones it idles and when it does at like 3,500-4,000 rpm (seems low) and sometimes if you let off the throttle it just stalls, if i start it back up it will fire, then stall and Check engine light goes on. Like I drove 25 miles, and about 15 miles into it, it would stall unless i kept it going, But then on the way back, it ran fine, (still idles low though) So could this be the Maf (mass air sensor) is bad?? what does your TPI engine idle at?

Thanks--
Old 08-10-2008, 12:40 PM
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Re: Car wont idle? MAF sensor? Whats your TPI idle at?

need help, car wont idel. sometimes does, sometimes doesnt,
Old 08-15-2008, 08:03 AM
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Re: Car wont idle? MAF sensor? Whats your TPI idle at?

Check/clean Idle Air Control motor on the Throttle Body
Old 08-15-2008, 11:42 AM
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Re: Car wont idle? MAF sensor? Whats your TPI idle at?

my car at stops idle a 800rpm, stable, before it was trying to stops at a stop or a red light! but it was a problem with the pci valve!
Old 08-15-2008, 02:32 PM
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Re: Car wont idle? MAF sensor? Whats your TPI idle at?

What is a PCI valve?

Positive Crankcase Ventilator maybe?
Old 08-15-2008, 04:04 PM
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Re: Car wont idle? MAF sensor? Whats your TPI idle at?

er its either pci or ecm ... not sure, its avalve that is openingat hight speed to lower the explosion temperature, in my case it was open all the time.
Old 08-15-2008, 04:44 PM
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Re: Car wont idle? MAF sensor? Whats your TPI idle at?

Originally Posted by Curtisyz54
Ok I have just a 305 TPI. Someones it idles and when it does at like 3,500-4,000 rpm (seems low) and sometimes if you let off the throttle it just stalls, if i start it back up it will fire, then stall and Check engine light goes on. Like I drove 25 miles, and about 15 miles into it, it would stall unless i kept it going, But then on the way back, it ran fine, (still idles low though) So could this be the Maf (mass air sensor) is bad?? what does your TPI engine idle at?

Thanks--
your idle can be adjusted using the piece that attaches to your throttlebody from the throttle cables. basically you just bend it with some plyers but thats hard to explain and thats probably a silly way to do it. if your car wasnt doing this before now and you didnt touch that throttle cable piece then its something else. to test the MAF, just unplug it and see if it runs the exact same way. if it does, then it COULD be your MAF. if you have your TPS unplugged or its not working, it will also run this way. and like someone else said, could be your IAC, may be no good. mine idles around 800rpms which is about normal, some run up to 1000 but supposed to be around 800. and i believe you are saying your car idles at 350 to 400rpms? cuz 3500 to 4000 is HIGH as heck. since it is so low, its likely you have and air leak of some sort, low compression, or your not getting much fuel. how much power does she get when you give it gas as you're driving? you can try adjusting your timing, maybe its way too low cuz you can have low idle from that. turn your distributor until it gets to 800rpms (or whats best, get you a timing gun) then you might want to tighten the distributor down so it doesnt move back. see how she runs after adjusting that and if it still stalls, then the problem was something else. normally if your MAF, TPS, or IAC were bad, you would idle high and normally at least near 2000rpms. its possible your injectors are bad. ohm then with a reader, unplugging them one at a time (when the engine is hot) and they should be at be between 11-16 ohms each. if any are below that, that particular one is probably no good. let us know what you get and narrow some of this stuff down and maybe we can come to another conclusion
Old 08-15-2008, 08:42 PM
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Re: Car wont idle? MAF sensor? Whats your TPI idle at?

Originally Posted by auth100488
er its either pci or ecm ... not sure, its avalve that is openingat hight speed to lower the explosion temperature, in my case it was open all the time.
Explosion temperature is in cylinder temperature which is lowered by recircluting exhaust gas at part throttle, this process is called EGR; Exhaust Gas Recirculation.
Old 08-15-2008, 10:06 PM
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Re: Car wont idle? MAF sensor? Whats your TPI idle at?

Originally Posted by armygreen87
your idle can be adjusted using the piece that attaches to your throttlebody from the throttle cables. basically you just bend it with some plyers but thats hard to explain and thats probably a silly way to do it. if your car wasnt doing this before now and you didnt touch that throttle cable piece then its something else. to test the MAF, just unplug it and see if it runs the exact same way. if it does, then it COULD be your MAF. if you have your TPS unplugged or its not working, it will also run this way. and like someone else said, could be your IAC, may be no good. mine idles around 800rpms which is about normal, some run up to 1000 but supposed to be around 800. and i believe you are saying your car idles at 350 to 400rpms? cuz 3500 to 4000 is HIGH as heck. since it is so low, its likely you have and air leak of some sort, low compression, or your not getting much fuel. how much power does she get when you give it gas as you're driving? you can try adjusting your timing, maybe its way too low cuz you can have low idle from that. turn your distributor until it gets to 800rpms (or whats best, get you a timing gun) then you might want to tighten the distributor down so it doesnt move back. see how she runs after adjusting that and if it still stalls, then the problem was something else. normally if your MAF, TPS, or IAC were bad, you would idle high and normally at least near 2000rpms. its possible your injectors are bad. ohm then with a reader, unplugging them one at a time (when the engine is hot) and they should be at be between 11-16 ohms each. if any are below that, that particular one is probably no good. let us know what you get and narrow some of this stuff down and maybe we can come to another conclusion

yeah woops i ment 350-400. And its low, But its runs GREAT no problems other then idel only sometimes. It didnt do it for like 4 days, And then today when i started it, it started then staled, start then stall. so I keep it running and drove it and didnt do it again all day tell later, I started it, thenstaled, same thing then it was fine. then shut it off for a min, and SAME THING!!
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