Engine running rough

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Mar 11, 2005 | 06:07 PM

1984 f-250

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From: Oregon

Engine running rough

on my 92 explorer when i press the gas it stumbles and then once its moving its fine. At idle the RPM jump between 800-1000. I have a new IAC, fuel filter, spark plugs and wires also i clean the MAF but it still runs poorly. Any ideas?

Mar 11, 2005 | 08:05 PM

JerrySimm

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From: Pauline, South Carolina

Have you checked for a vacuum leak? Check the hoses and the intake hose tree back near the brake boster. Have you tried pulling any codes from the computer?

Mar 11, 2005 | 08:53 PM

1984 f-250

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From: Oregon

I looked at the vacuum tree and it seemed ok. Does anyone know of the website that shows how to pull the OBD 1 codes.

Last edited by 1984 f-250; Mar 11, 2005 at 08:58 PM.

Mar 11, 2005 | 08:58 PM

JerrySimm

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From: Pauline, South Carolina

You can either go get a code reader from the parts store, or you can try the procedures shown here http://dalidesign.com/hbook/eectest.html . Also, some parts stores will pull the codes for you in hopes that you'll buy parts to fix the problem.

Mar 12, 2005 | 10:43 PM

1984 f-250

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Can anything else cause the idle to drop to 500-700 rpms other than the IAC

Mar 12, 2005 | 11:11 PM

mrshorty

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From: UT

Other interruption in air intake, dip in the fuel pressure, misfire, vacuum leak, other EEC-IV problem.
Have you pulled codes, yet? Can you test fuel pressure?