Idle dips

Reply Subscribe

Thread Tools

Search this Thread

Nov 29, 2005 | 09:05 PM

Black88GT

Thread Starter

Elder User

Joined: Jun 2003

Posts: 642

Likes: 0

From: Bay Area, CA

Idle dips

What would cause the idle to dip? I hold it at say 1700 rpms, and every 10 seconds or so it will drop 400 rpms for a second then go back up. Is there something pulling juice? I had the defrost and everything off. Thanks

Nov 30, 2005 | 09:55 PM

cookie88

FTE Leadership Emeritus

Joined: May 2001

Posts: 13,653

Likes: 6

From: Cabot, Arkansas

Mine does that all the time when the compressor cycles, but with it off....

An irregular signal from the ICP, or a bit of trash in the IPR maybe??

Dec 1, 2005 | 12:20 AM

Kwikkordead

Fleet Owner

Joined: Jun 2004

Posts: 25,090

Likes: 1,111

From: Rio Rico, AZ.

More info needed: when it drops does it sound like a cylinder is dropping?

Dec 1, 2005 | 06:38 AM

Black88GT

Thread Starter

Elder User

Joined: Jun 2003

Posts: 642

Likes: 0

From: Bay Area, CA

Thanks guys, To me it sounds like when you run the AC or the defrost, you know how it put a small load on the motor? Thats kinda what it sounds like

Dec 1, 2005 | 07:59 AM

Kwikkordead

Fleet Owner

Joined: Jun 2004

Posts: 25,090

Likes: 1,111

From: Rio Rico, AZ.

Yeah 400 rpm drop is too much to just be AC cycling on and off. Gotta be a sensor acting up or something. My first thought is the IPR or the HPOP pressure sensor going south or at the very least a poor connection to one or both.

Dec 1, 2005 | 12:31 PM

Wings

Senior User

Joined: Sep 2005

Posts: 274

Likes: 0

From: Southern California

I have to agree with Kwik. Hey guys is there a good engine electrical diagram to download on all or most of the sensors and their locations? Sometimes I read over these threads and really wonder where the heck is this one. LOL. I am sure all would benifit.

Thanks Wings

Dec 1, 2005 | 09:24 PM

cookie88

FTE Leadership Emeritus

Joined: May 2001

Posts: 13,653

Likes: 6

From: Cabot, Arkansas

This one is decent. Though I do not believe it is an exact reproduction as I have run across a few discrepancies.

http://www.nav-international.com.br/...rStroke/hs.asp