89 300 E surging idle
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89 300e
89 300 E surging idle
The car has 140K miles. It starts right up but then idles between 500RPM and 1500RPM and cycles. It runs great at high speed though. I see a lot of discussion on this but I dont see a consesus of possible problems. I replaced the two fuel pumps and filter thinking that was the problem but it wasnt.
A second problem is the interior heater/AC fan doesnt work, which is an unrelated (i think) problem and of course not as serious.
Any ideas on what it could be?
Thanks
A second problem is the interior heater/AC fan doesnt work, which is an unrelated (i think) problem and of course not as serious.
Any ideas on what it could be?
Thanks
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89 300e
Thanks for the reply. I understand that it could be a number of things, but I was hoping there was a good mechanic on this forum that could point me in the right direction to run a few checks. As an engineer, I do most mechanical work on cars myself.
Thanks
Thanks
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89 300e
Thats funny, I'm actually very good at searching! When I search for the document you posted- "ra0703ke2g030x", nothing comes up but your post! If you want to be helpful, and Im sure you do since you bothered to respond, despite your sarcasm, I'd apprectiate you send me the link to this document.
In my other searching outside this forum, I found that the problem may be the MAF sensor that is causing the surging idle. So I'll check that out this weekend.
In my other searching outside this forum, I found that the problem may be the MAF sensor that is causing the surging idle. So I'll check that out this weekend.
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From: Southern California
1992 300E 3.0L
This thread may be dead... but I figured I'd toss in my $0.02
I had exactly the same issue as described, the problem ended up being the throttle position switch.
Might be worth checking out.
I attached a photo and the part # i found for it was this:
0025456814
Switch; Thrust Cut-Off Micro-Switch at Throttle Linkage on Intake Manifold with Single Roller/Lever
By quickly looking at the throttle assembly, it's clearly visible. Most likely will have to remove the air filter to get a good look at it.
I had exactly the same issue as described, the problem ended up being the throttle position switch.
Might be worth checking out.
I attached a photo and the part # i found for it was this:
0025456814
Switch; Thrust Cut-Off Micro-Switch at Throttle Linkage on Intake Manifold with Single Roller/Lever
By quickly looking at the throttle assembly, it's clearly visible. Most likely will have to remove the air filter to get a good look at it.
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89 300e
Thanks everyone-- I finally fixed the problem. The biggest clue was that the ABS light was on, which I didn't mention thinking the brakes have nothing to do with engine operation. I'm sure if I did one of the experts out there would have said replace the OVP relay. However by searching all over, I saw that the OVP relay powers both the engine computer and the ABS system and when it goes which it frequently does, the symptoms I had are common. I bought a used one on ebay for $$12 plus shipping and now the car runs great! with no ABS light.
Also thanks for the tip on the blower relay, I'll check that tomorrow. I think also the wiper doesn't work now.
Also thanks for the tip on the blower relay, I'll check that tomorrow. I think also the wiper doesn't work now.
