Idle Climbs When Thoroughly Warmed-Up

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John Brennan
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Idle Climbs When Thoroughly Warmed-Up

Post by John Brennan » Wed Nov 02, 2005 6:55 pm

Lately, I've been noticed a weird idle climb, to 1500 or even more, after the car's been run a while, stuck in traffic, or thoroughly heat-cycled. A shorter drive won't do it, and when I first start it and it warms up, the idle drops down normally to ~900. I will do my due diligence and try to track down vacuum leaks, check TPS settings, etc., but I've kept up on that pretty much, and my past experience tells me that if those aren't right, the engine won't idle right in the first place. Does this ring any bells?
This is my car, and these are my people!
1989 XR4Ti 5-Speed
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Ed Lijewski
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Post by Ed Lijewski » Wed Nov 02, 2005 8:02 pm

Certainly consider any/all of the usual suspects. Several have been named already by you and Alex. If it were my problem I'd also routinely clean/service the TB and throttle linkage as well as the IAC; check each turbo hose and clamps, and also remove and clean the EGR. As well, I'd check tightness on each nut/bolt on both sections of the the intake manifold, and I'd clean the VAM. Don't forget to check the vacuum reservoir hoses and the blend door solenoid motor hose. If that doesn't solve the problem, I might consider replacing the coolant temperature sender if the one you have has seen a lot of service.

Good luck. :wink:

YMMV 8)

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John Brennan
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Post by John Brennan » Wed Nov 02, 2005 8:30 pm

The ECT is brand-new, and when I pulled the turbo hoses off, I saw very little oil in the VAM and virtually nothing in the TB. I suppose I'll have to dig into the IAC and perhaps the EGR, but it hasn't been that long...

I know I shouldn't ask the question until I've checked EVERYTHING, but sometimes I get lazy! :?
This is my car, and these are my people!
1989 XR4Ti 5-Speed
2001 BMW Z3 3.0 5-Speed
2015 Fiesta ST 6-Speed
2015 Edge 3.5 V6 Auto/Paddles

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Post by jkxr4ti » Thu Nov 03, 2005 2:09 am

John, if you have build up in the throttle body you probably wont see it by just removing the hose. Ask me how i know. The build up occurs behind the throttle plateas it comes in through the EGR. If your thinking of cleaning the IAC take off the trottle body and IAC as one unit and save yourself a headache or two.

Good luck
Merkur....Its German for Mutt....Mustang, Saab, Volvo, Lincoln, Contour, Cummins... and the list goes on.

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Post by Shigma » Thu Nov 03, 2005 12:55 pm

Mine did it after I swapped the LA3 in, mine cleared up by adjusting the TPS and tweaking the idle control screw
01 Cavalier - it still runs!
08 Evo X GSR - Stock.. for now

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Post by mangostick » Thu Nov 03, 2005 5:36 pm

Are you getting any codes? I had a loose connection at the vam recently that gave me a 54... (air temp sensor open circuit) and was playing hell with driveability and Idle speed when warm. ... I suspect you've already run the codes no? ...
where'd I put that damned hammer?? :-D

Shawn Mangan

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John Brennan
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Post by John Brennan » Thu Nov 03, 2005 5:40 pm

I'll do it all again, and thanks. Just ran the codes before moving here, but-- new climate, different driving, etc... I'll get on all that thoroughly just as soon as it stops raining! Really need to clear out the garage!
This is my car, and these are my people!
1989 XR4Ti 5-Speed
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2015 Fiesta ST 6-Speed
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Post by Ed Lijewski » Thu Nov 03, 2005 5:48 pm

John Brennan wrote:I'll do it all again, and thanks. Just ran the codes before moving here, but-- new climate, different driving, etc... I'll get on all that thoroughly just as soon as it stops raining! Really need to clear out the garage!

Raining?! Something different, eh? I bet the wiper blades on that Phoenix-bred beauty are still original--from lack of use :!: :P :lol: :wink:

YMMV 8)

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John Brennan
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Post by John Brennan » Thu Nov 03, 2005 6:08 pm

No, 'cause the sun cooks 'em real bad in the desert. When it rains there, it really pours, so you have to stay on top of that. People are more often caught by surprise there, because it might not rain for months, and then one day the heavens open and people activate the wiper switch to find their wipers literally fused to the windshield! Then they pop loose, and you've got two-piece wiper blades (ask me how I know...)!

That said, yes, they do need to be replaced, though they're not too bad yet. I got some nice new ones for the Explorer already-- always thinking about the wife and kiddies first.

I found that my blow-by issues, which were previously the cause of much intake contamination, were vastly reduced by my cylinder head rebuild. Perhaps the bottom end, at 168,000 miles, is beginning to significantly lose compression now. I'll let y'all know what I find out.
This is my car, and these are my people!
1989 XR4Ti 5-Speed
2001 BMW Z3 3.0 5-Speed
2015 Fiesta ST 6-Speed
2015 Edge 3.5 V6 Auto/Paddles

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Post by richardcurtis » Thu Nov 03, 2005 11:39 pm

Check TPS for no hiccups when you've got the DVM hooked up and move the throttle from idle to WOT. Does the idle drop back down if you tap the accelerator? (An old timer like you knows this, I'm sure, so pardon me for stating the obvious.)
Richard Curtis
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Post by vcallaway » Fri Nov 04, 2005 12:55 am

This is going to sound kind of dumb, but I had a similar issue after replacing my ECT sensor. I did not discover the actuall reason until the car failed to start.

My plug on the ECT was loose. All I did was reach in and push down REALLY HARD.

Visually it looked fine, but it was not seated good.
Vince Callaway

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Post by Ed Lijewski » Mon Nov 07, 2005 1:48 pm

Ditto; that sort of thing--as well as cleaning the contacts there--was what I was pointing to in my comments earlier. :wink:

8)

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John Brennan
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Post by John Brennan » Mon Nov 07, 2005 6:29 pm

Well, the sun came out yesterday, and is poking out today, but wouldn't 'ya know it, I wrenched my shoulder the other night at work-- very painful; went to the ER and they tell me it's tendonitis-- follow-up in a couple of days. Sucks getting old-- the warranty's definitely expired!

However, I'll get out there and see what I can do-- running codes and checking TPS should be doable-- thanks, all.
This is my car, and these are my people!
1989 XR4Ti 5-Speed
2001 BMW Z3 3.0 5-Speed
2015 Fiesta ST 6-Speed
2015 Edge 3.5 V6 Auto/Paddles

Ed Lijewski
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Post by Ed Lijewski » Mon Nov 07, 2005 6:33 pm

I bet you wrenched it AFTER work, during that ride home that was memorialized in your recent novella; if it's the right shoulder, it was from energetically selecting gears upward and downward; if it's the left shoulder it wa from lively but firm twists of the steering wheel to induce gradations of oversteer/udnersteer/oversteer/understeer--well, you get the point. :lol: :wink:

YMMV 8)

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