Rough Idling

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Jun 6, 2008 | 02:03 PM

$300vett

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From: Roanoke Rapids NC

Rough Idling

Ok I have done a lot of work on this car-1985 (replace the ECM, MAS, COIL, WIRES, PLUGS, O2 SENSOR, and the TPS.. Check the fuel pressure it was with in the specs. Also check for vacum leaks cannot find any. It will crank and run fine. But when it returns to idle it will start to surge from 7000 to 4400 and finally it will cut off. Running out of ideas-- No code or check enging light is comming on.
Thanks $300vett

PS.. How do you check the omhs for the fuel injectors. How much should it be??

Last edited by $300vett; Jun 6, 2008 at 03:10 PM.

Jun 6, 2008 | 11:28 PM

FICINJECTORS

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From: Cumming Ga

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Originally Posted by $300vett

to check the resistance of the injector coil you have to first remove the electrical connector on the injector. there are 2 terminals on the injector. Attach a lead from an ohm meter on each of the termnals. Your ohm meter will measure the resistance of the coil. They should be between 12-16 ohms with all eight being within +-.5 ohms of each other

Jun 7, 2008 | 12:22 AM

cwyates4

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From: Jasper Texas

Looking at what all you changed, it is very likely to be a couple of bad injectors. Is the idle rough when cold?, warm?, both? Details please.

Jun 7, 2008 | 11:23 AM

$300vett

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From: Roanoke Rapids NC

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Originally Posted by cwyates4

Looking at what all you changed, it is very likely to be a couple of bad injectors. Is the idle rough when cold?, warm?, both? Details please.

It idles bad when it is cold and warm.. I also just change the IAC valve... When you check the injectors (dumb qustion) is the motor running or off.... Also check the TPS and it is at .545-- acccording to Haynes --.54 So I am thinking maybe the EGR valve or Injectors... I read somewhere about (GM intake cleaner -aka Spray bomb.. Can't find it anywhere.....

Thanks $300vett

Last edited by $300vett; Jun 7, 2008 at 11:29 AM.

Jun 7, 2008 | 12:01 PM

FICINJECTORS

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From: Cumming Ga

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Originally Posted by $300vett

you have to remove the electrical connector off the injector to check it.. motor off. Pull all the connectors and check each one of the eight.. record the readings and post it here.

Jun 7, 2008 | 12:23 PM

$300vett

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From: Roanoke Rapids NC

Quote:

Originally Posted by FICINJECTORS

you have to remove the electrical connector off the injector to check it.. motor off. Pull all the connectors and check each one of the eight.. record the readings and post it here.

Thanks-- 7 injectors are reading between 17.6 and 18.0 and one reading 13.5.. is the #6 cyclinder..

Last edited by $300vett; Jun 7, 2008 at 12:29 PM.

Jun 7, 2008 | 12:59 PM

FICINJECTORS

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From: Cumming Ga

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Originally Posted by $300vett

Thanks-- 7 injectors are reading between 17.6 and 18.0 and one reading 13.5.. is the #6 cyclinder..

that should not cause you symtoms unless 1 is clogged. There is no on the car check to tell. is the one with the different ohms a replacement that might of been changed?

Jun 7, 2008 | 01:24 PM

$300vett

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From: Roanoke Rapids NC

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Originally Posted by FICINJECTORS

that should not cause you symtoms unless 1 is clogged. There is no on the car check to tell. is the one with the different ohms a replacement that might of been changed?

No I don't think so.. but when I change out the IAC valve it was really dirty---lots of black carbon... Have you ever heard of a (Spray bomb)... for cleaning the intake and the EGR valve?? Is there a easy way to check the EGR valve?

Last edited by $300vett; Jun 7, 2008 at 02:26 PM.