Pulsating engine

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Jun 2, 2006 | 07:47 PM

trike1946

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From: NJ where fun comes to die

Pulsating engine

What causes an engine to pulsate at idle? The rpms go up and down constantly, but even out when moving. It doesn't seem to be a problem now, but I didn't think it was supposed to do it. It is my 96 that is doing it. Thank you for any help.

Jun 3, 2006 | 12:09 PM

cookie88

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From: Cabot, Arkansas

Generally it's an oil system problem. ICP sensor, IPR valve or o-rings, Injectors.

Could also be as simple as needing the oil of fuel filter changed.

Jun 3, 2006 | 04:58 PM

trike1946

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From: NJ where fun comes to die

Thanks for the reply. Would any of those show up as a code? If not is there a way to check them? I just changed the oil and filter and fuel filter about two weeks ago. It made no difference.

Jun 3, 2006 | 10:19 PM

cookie88

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From: Cabot, Arkansas

Yes. There are several codes that the ICP sensor can trigger.

Jun 4, 2006 | 05:09 AM

Jaaaaaaackman

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Quote:

Originally Posted by cookie88

Could also be as simple as needing the oil of fuel filter changed.

Hey Cookie88 are you speaking of the engine oil and the fuel filter? I can understand a clogged fuel filter, but whats engine oil got to do with surging?

Jun 4, 2006 | 02:37 PM

1997F-350

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From: SHELTON, WA

a hpx helped mine out. it idles perfectly smooth now.
oil has everything to do with the idle.

Jun 4, 2006 | 04:04 PM

cookie88

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From: Cabot, Arkansas

Quote:

Originally Posted by Jaaaaaaackman

Hey Cookie88 are you speaking of the engine oil and the fuel filter? I can understand a clogged fuel filter, but whats engine oil got to do with surging?

The injectors are fired by high pressure oil. All sorts of funny little idle/drivability issues can crop up from old tired oil.

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Jun 4, 2006 | 05:22 PM

Riata_Ag

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Joined: Apr 2006

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From: I-45, Texas

Quote:

Originally Posted by 1997F-350

a hpx helped mine out. it idles perfectly smooth now.
oil has everything to do with the idle.

What is a hpx?

My '97 has a little lope to her when you first stop and place the tranny into P.

In about 2 seconds the engine smooths out.

maybe I need a hpx..............

the Ford dealer has been changing the oil in this truck prior to my purchase.

I have no idea what brand of oil they use..............maybe I need to go ahead and drain her and give her a taste of some rotella............