Idle sticks at 2000~2500 rpm
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Joined: Oct 2007
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88 260e, 94 toyota 4runner, 98 ZX2
Idle sticks at 2000~2500 rpm
I had the heads done I replaced the temp sensor. I replaced the Idle speed control valve but the problem is with the signal that goes to the idle speed control valve.
I haven't driven this car since the battery was off so I don't know if I need to drive a while so settings can be put back into the control module.
I can remove the connector to the idle speed control and the rpm goes back down and idles correctly. I then plug the connector back in and it stays at idle unless I rev the engine. WHen I rev the engine it stays at 2000~2500 rpm.
If I turn off the engine and restart it will go right back to idle.
I tried turning on the AC then back off to see if it would change the idle and it does just a little but it still stays at 2000~2500 rpm. Also at idle the engine surges from 750~850 back and forth.
Do I need a new KE Injection ECM? Wire issue or what?
Any ideas
Thanks Anthony
I haven't driven this car since the battery was off so I don't know if I need to drive a while so settings can be put back into the control module.
I can remove the connector to the idle speed control and the rpm goes back down and idles correctly. I then plug the connector back in and it stays at idle unless I rev the engine. WHen I rev the engine it stays at 2000~2500 rpm.
If I turn off the engine and restart it will go right back to idle.
I tried turning on the AC then back off to see if it would change the idle and it does just a little but it still stays at 2000~2500 rpm. Also at idle the engine surges from 750~850 back and forth.
Do I need a new KE Injection ECM? Wire issue or what?
Any ideas
Thanks Anthony
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Idle sticks at 2000-2500 rpm
It sound like you have a vacuum leak problem to me, because if you pull the connector off of the idle air valve the engine would die rightaway , I did it lots off times to my 260E and the second I pull that connector off the engine stops running because it can breath anymore. So you must have a vacuum leak ,their is a vacuum hose somewhere that was not put back properly or put back at all or a vacuum hose that might have gotton broken buring the head job.
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88 260e, 94 toyota 4runner, 98 ZX2
Vaccume leak???/
I think I do have a vacuume leak but I cant find it. I replaced intake manifold gasket and my vaccum pressure went from around 10~12 to 15~16 at idle. I tried removing all of the vaccum lines off of the manifold except for the brake booster and the vaccum stays the same...
Where to check next?
Where to check next?
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88 260e, 94 toyota 4runner, 98 ZX2
mixture control unit?
Do you think it could be the mixture control unit?
I took this off and took it apart and cleaned the inside when I did the headjob. Could this be the culprit?
I am going to take off and take apart again and RTV the bottom seal. There are cracks in the rubber as well I am going to RTV those cracks as well.
It definately does not stall when I take off the connector to the idle speed control valve. As a matter of fact at idle it has no effect. I tried covering the sensor plate with a rag and my hand and it would not stall it just ran at idle.
Something very wrong here just don't know what it is....
I took this off and took it apart and cleaned the inside when I did the headjob. Could this be the culprit?
I am going to take off and take apart again and RTV the bottom seal. There are cracks in the rubber as well I am going to RTV those cracks as well.
It definately does not stall when I take off the connector to the idle speed control valve. As a matter of fact at idle it has no effect. I tried covering the sensor plate with a rag and my hand and it would not stall it just ran at idle.
Something very wrong here just don't know what it is....
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From: Bellevue, NE
1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
Verify the idle valve is closing completely by disconnecting and plugging one of its hoses. The engine should not idle at all. If it doesn't, your idle valve is sticking open. If it remains unchanged then there is a leak external to the idle air circuit.
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88 260e, 94 toyota 4runner, 98 ZX2
Thanks sooo much.
First off I have 2 idle air valves and they are open just a little bit without voltage being applied. The gap looks the same on both. So the valve is suppost to be open a little.
I have removed mixture unit and butterfly unit below. I sealed everything real well. I also notice a little bit of oil in the bottom of the intake. I have cleaned this out several times and it keeps comming back. Where could this oil come from ? Brake booster? I check all the lines and cannot find where its comming from.
I do see how the Idle air valve works. It takes air from the mixture unit directly into the manifold. I will try and block this off and see if it dies--
It wont start without the idle valve installed. I tried removing it and there was a massive vaccum leak. I tried plugging the hose and it still wouldn't start.
I just don't know where else to look.
I did remove the KE injection unit and resoldered all the connections.
Will try this and test.
Thanks Anthony
I have removed mixture unit and butterfly unit below. I sealed everything real well. I also notice a little bit of oil in the bottom of the intake. I have cleaned this out several times and it keeps comming back. Where could this oil come from ? Brake booster? I check all the lines and cannot find where its comming from.
I do see how the Idle air valve works. It takes air from the mixture unit directly into the manifold. I will try and block this off and see if it dies--
It wont start without the idle valve installed. I tried removing it and there was a massive vaccum leak. I tried plugging the hose and it still wouldn't start.
I just don't know where else to look.
I did remove the KE injection unit and resoldered all the connections.
Will try this and test.
Thanks Anthony
Last edited by cnctony; Oct 10, 2007 at 05:16 PM.
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1995 e320 sedan
