Vanagon EuroVan
Previous messageNext messagePrevious in topicNext in topicPrevious by same authorNext by same authorPrevious page (August 2012, week 1)Back to main VANAGON pageJoin or leave VANAGON (or change settings)ReplyPost a new messageSearchProportional fontNon-proportional font
Date:         Wed, 1 Aug 2012 21:20:33 -0400
Reply-To:     Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject:      Re: Idle control system
Comments: To: Steven Sittser <ssittservl@AOL.COM>
In-Reply-To:  <8CF3E3598DDB907-15F8-5F29@webmail-m139.sysops.aol.com>
Content-Type: text/plain; charset="us-ascii"

Another possibility is that the AC system is overcharged causing too much load on the engine! Does the van run well except for the idle?

Dennis

-----Original Message----- From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Steven Sittser Sent: Wednesday, August 01, 2012 3:47 PM To: vanagon@GERRY.VANAGON.COM Subject: Re: Idle control system

Dennis Haynes wrote:

> Does the engine idle near set speed with the valve electrically > disconnected?

Yes.

> Set idles speed to at least 850 without the valves help.

It's at approximately that now.

> Even with the valve not operating the engine should be able to carry > the AC load. Idle speed will drop but it should keep running.

In my case, the engine can't carry the A/C load unless the idle is set very high.

> It is possible you have an engine performance issue and the idle valve > can't compensate.

That's possible. It's not particularly smooth running, but the incompetent shop supposedly did a thorough refurbishing of it. The engine is an AVP rebuild from about 6 years ago. The incompetent shop claimed that AVP did a terrible job on the rebuild, but my confidence in their opinion is not particularly high. They're one of those "everyone's work but ours is garbage; all parts but those we sell are garbage" places. There was a large gap between their arrogance and their performance.

Since the idle valve doesn't adjust when it's hooked up and the engine's running, though (it's always closed), I do have at least an idle control system problem, separate from any engine performance issues.

Neil wrote:

> ... when you turn the steering hard right or left, the input from the > PS switch should audibly cause the idle stabilization system to adjust > the idle. The PS switch is easy to check.

I tested the PS switch a while back, and it's fine. (I repaired the questionable wiring connection to it.) I didn't test the PS input at the module (which would effectively just be testing the wiring), but since the problem occurs with A/C as well as PS it's not an issue.

> Re: coolant temp sensor. There is a graph in Bentley showing coolant > temps and corresponding resistance. With an infrared gun or other > means to measure coolant temp, you should easily be able to confirm > things.

I looked the graph, but I wasn't sure which of the two sensors (or both) it covered, and which connects to the idle control module. According to the graph, 250 ohms would indicate 100 Celsius, which is hotter than I expected for a merely warm engine, but I wasn't sure if I was looking at the right graph. To be thorough, I should check the input at a few different engine temperatures and make sure the resistance changes in some reasonable way

> There is a fellow in Canada who sells the ISV control modules. I'm not > suggesting "throwing parts" at the issue, but the in case you want a > spare.... > > http://benplace.com/parts_sale1.htm

I contacted Ben for an idle control valve (since he says he tests his used parts thoroughly), but he's out of them. If there's a problem with the idle control module, then I think Module Master will probably re-repair it under warranty, or at least re-test it and verify that that's the problem.

> I noticed it's easy to have a termination push out of the block the > idle stabilization module plugs into. Be sure the connectors are clean > and properly seated.

I checked - putting 12V on the ST1 & ST2 connections on the idle control module connector will cause the idle control valve piston to move, so the connection is good.

> The throttle valve switch, as I'm learning, can be affected by a worn > throttle body. This is mentioned in Bentley. What I experienced is > that if the throttle is "let down" to idle slowly, the shaft can come > to rest in one position, then, possibly move to yet another rest > position. My *guess* is that with a really worn TB shaft, this issue > can be worse and can make TVS adjustment tough.

Throttle body was recently replaced, so in theory this should be OK.

Thanks for the help!

- Steven


Back to: Top of message | Previous page | Main VANAGON page

Please note - During the past 17 years of operation, several gigabytes of Vanagon mail messages have been archived. Searching the entire collection will take up to five minutes to complete. Please be patient!


Return to the archives @ gerry.vanagon.com


The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.

Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.