SlIght fluctuation at idle

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Apr 7, 2021 | 05:29 AM

Txadvrider

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From: Bosque County Texas

SlIght fluctuation at idle

on my 97 psd, i get a RPM fluctuation every 3 or 4 seconds. It drops 100 to 200 rpm. I unplugged the ICP and it goes away. I guess ICP NEEDS replacing? Everything else is fine as far as drivability and starting. Icp connecter is clean with zero oil residue.

Apr 7, 2021 | 07:22 AM

TheFecalFanatic

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From: NT, See you in the

Could be the connector as well. Neither the sensor nor the pigtail is cheap to replace though. Soon as you replace one it'll always be the other one that's the issue...

Apr 7, 2021 | 11:16 AM

gtex

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From: Texas

I think mine has a light "surging" at idle as well. is that not normal? I just wonder if my ears are being to sensitive.

Apr 7, 2021 | 01:28 PM

Bitterroot Diesel

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From: Florence, MT

Sounds like the PCM is providing constant correction due to something...fuel, electrical, sensor.

Apr 7, 2021 | 01:53 PM

96 OBS

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From: Fowler Colorado

Funny mine has the same thing. I’ve been trying to figure it out for a while

Apr 7, 2021 | 07:29 PM

z31freakify

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From: Las Cruces New Mexico

You sure it's not the AC compressor cycling on/off?

Apr 7, 2021 | 07:30 PM

96 OBS

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Joined: Oct 2019

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From: Fowler Colorado

Quote:

Originally Posted by z31freakify

You sure it's not the AC compressor cycling on/off?

AC off for me

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Apr 9, 2021 | 07:15 PM

pilgrimbizket

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Joined: May 2012

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From: Central Oregon

Mine does the same thing also. It dosent happen all the time, but occasionally. I have a new ICP IPR HPOP, injectors are the only thing that have never been touched.

Apr 10, 2021 | 01:12 AM

#10

Tanker1

4wd Low

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are you sure it doesn't matter? it could be a fly getting sucked into the intake. don't you have something better to do?

Apr 10, 2021 | 08:04 AM

#11

96 OBS

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From: Fowler Colorado

Quote:

Originally Posted by Tanker1

are you sure it doesn't matter? it could be a fly getting sucked into the intake. don't you have something better to do?

pretty sure if there’s flys getting into the intake you have other things to worry about yourself

Apr 10, 2021 | 09:21 AM

#12

Txadvrider

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From: Bosque County Texas

Quote:

Originally Posted by Tanker1

are you sure it doesn't matter? it could be a fly getting sucked into the intake. don't you have something better to do?

that was kind of my point for posting...to see if they all do it OR if its a prob with my 97.

Apr 10, 2021 | 02:11 PM

#13

Hit Man X

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From: North Texas

Dually does it. Easier to spot with the AC on...I blame it on early 90s electronics. I never cared.

Apr 10, 2021 | 02:24 PM

#14

Txadvrider

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From: Bosque County Texas

Quote:

Originally Posted by Hit Man X

Dually does it. Easier to spot with the AC on...I blame it on early 90s electronics. I never cared.

well that makes me feel a little at ease Hitman. Seems to be somewhat common...

Apr 10, 2021 | 04:48 PM

#15

BuddyBarnes

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From: Fl.

Quote:

Originally Posted by Txadvrider

well that makes me feel a little at ease Hitman. Seems to be somewhat common...

It has become more common after they changed the diesel oil formula to work with the newer trucks. This has been the topic of a few post in the past. If you have the time and desire you could check some of my comments under my profile or do a search on here for some info. Yes a lot of us have chased this in the past and as far as I know no one has found the answer. Yes mine does it too.