1989 260e Idle Too High
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1989 260E
1989 260e Idle Too High
1989 260E, 190,000 miles.
Just in the last few days, all of a sudden, the idle, in neutral or park, is about 1500 RPM. After driving 10-15 miles, I stop, place in neutral, it drops a bit from 1500 to 1200 RPM, but still too high.
In drive, at idle, it will drop to about 900 RPM, but it used to be about 6-700.
I looked at all the vacuum lines, rechecked them again, car runs fine, just the idle.
I'm thinking maybe the Idle Control Valve needs cleaning or replaced. Trouble is, the 2 hoses on each side are of course original, and I'm afraid they might break or split if I try to take them off. Only way to clean is to spray some brakecleen or something in there, right?
On the other hand, someone told me the Idle Control Valve has a breather hose to keep the gunk out of there, unlike most other vehicles. Is this the 2 hoses on either side?
Or, it may just be a sender somewhere going bad, possibly sending the wrong signal to the ICV. I wouldn't know which one, or how to test, but I do have an ohm meter.
Also tracking down a Haynes manual for this thing is near impossible.
Any help is highly appreciated, thanks in advance!
UPDATE: It did it this morning, (I keep it garaged), started up, idle too high, drove to work, which is about 10 miles away. Stopped at work, place in neutral or park, idle too high. After work, started up, idle too high, but, when I pulled into the garage at home, stopped, idle was perfect, everything normal. I dont get it. Something is sticky or intermittant.
Just in the last few days, all of a sudden, the idle, in neutral or park, is about 1500 RPM. After driving 10-15 miles, I stop, place in neutral, it drops a bit from 1500 to 1200 RPM, but still too high.
In drive, at idle, it will drop to about 900 RPM, but it used to be about 6-700.
I looked at all the vacuum lines, rechecked them again, car runs fine, just the idle.
I'm thinking maybe the Idle Control Valve needs cleaning or replaced. Trouble is, the 2 hoses on each side are of course original, and I'm afraid they might break or split if I try to take them off. Only way to clean is to spray some brakecleen or something in there, right?
On the other hand, someone told me the Idle Control Valve has a breather hose to keep the gunk out of there, unlike most other vehicles. Is this the 2 hoses on either side?
Or, it may just be a sender somewhere going bad, possibly sending the wrong signal to the ICV. I wouldn't know which one, or how to test, but I do have an ohm meter.
Also tracking down a Haynes manual for this thing is near impossible.
Any help is highly appreciated, thanks in advance!
UPDATE: It did it this morning, (I keep it garaged), started up, idle too high, drove to work, which is about 10 miles away. Stopped at work, place in neutral or park, idle too high. After work, started up, idle too high, but, when I pulled into the garage at home, stopped, idle was perfect, everything normal. I dont get it. Something is sticky or intermittant.
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1989 260E
Update
So it's not a cold/hot issue either.
When I got home today, it idled perfect again.
Then, 5 minutes later, I had to go to the store, and it started the cycle again: 1500 RPM at idle, 900 in drive. Then drove to the store and back, never came back down again.
This has got to be a sticky idle control valve?
When I got home today, it idled perfect again.
Then, 5 minutes later, I had to go to the store, and it started the cycle again: 1500 RPM at idle, 900 in drive. Then drove to the store and back, never came back down again.
This has got to be a sticky idle control valve?
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1989 260E
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Take it completely off. You don't need to take anything else off. Just unplug the rubber vacuum hoses both sides (just unplug, don't pull it completely out from the other end down below the assembly. You don't need to), the 2 bolts, and lift it out. That is it!
If you take off one side, you sure you want all the dirt to go back into the engine when you spray one end? So do it right and take it completely out. Goodluck!
If you take off one side, you sure you want all the dirt to go back into the engine when you spray one end? So do it right and take it completely out. Goodluck!
Last edited by ps2cho; Feb 16, 2010 at 11:25 PM.
Thread Starter
Newbie
Joined: Feb 2010
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1989 260E
Take it completely off. You don't need to take anything else off. Just unplug the rubber vacuum hoses both sides (just unplug, don't pull it completely out from the other end down below the assembly. You don't need to), the 2 bolts, and lift it out. That is it!
If you take off one side, you sure you want all the dirt to go back into the engine when you spray one end? So do it right and take it completely out. Goodluck!
If you take off one side, you sure you want all the dirt to go back into the engine when you spray one end? So do it right and take it completely out. Goodluck!
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1989 260E
Well that didn't work
I took off the ICV, cleaned it with carb clean. When I took it off, it really looked pretty clean inside to me. Some dirt came out when spraying, but not much. I can move the little metal door with a small screwdriver easily, and it springs back with no drag, seems smooth and seems to operate normally.
Put it back on, no change. Idle at 14-1500 RPM. After a few minutes, it will gradually drop to about 1200 RPM, but will not completely idle normal unless I drive it around, like 5 or 10 miles.
Then I took the wires off the ICV. Now it idled perfect. But gunning it at idle a few times proved that was not going to work. Not smooth out and back into the idle circuit without those wires, and even a bit of very light backfire. Nope, I put the wires back on, and now I'm back to square one.
Anybody got any ideas?
Put it back on, no change. Idle at 14-1500 RPM. After a few minutes, it will gradually drop to about 1200 RPM, but will not completely idle normal unless I drive it around, like 5 or 10 miles.
Then I took the wires off the ICV. Now it idled perfect. But gunning it at idle a few times proved that was not going to work. Not smooth out and back into the idle circuit without those wires, and even a bit of very light backfire. Nope, I put the wires back on, and now I'm back to square one.
Anybody got any ideas?
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I would comment and say my engine temp sensor broke (literally I snapped it in half) and it did not show any raised idle rpm issues, just a rough idle only when cold...but then I have the two prong one and not the updated "plug" type. Not sure if it made changes other than reports for error codes.
I would lean towards saying its the same unit just with the extra error handling for code pulling. So IMO I doubt that is the problem part.
To check operation of the ICV, you need to apply a 12V battery to the poles and listen for a "click".
Make sure to check for vacuum leaks and make sure the air flow plate is centered correctly.
I would lean towards saying its the same unit just with the extra error handling for code pulling. So IMO I doubt that is the problem part.
To check operation of the ICV, you need to apply a 12V battery to the poles and listen for a "click".
Make sure to check for vacuum leaks and make sure the air flow plate is centered correctly.
Last edited by ps2cho; Feb 17, 2010 at 10:59 PM.
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1989 260E
Make sure to check for vacuum leaks and make sure the air flow plate is centered correctly.
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1989 260E
I'm losing my mind
Todays fun:
Started up this morning, idled @ 1500 RPM.
Went to store. Then decided to drive around a bit to see if it would drop. Drive about 5 miles, stopped. Idle still 1500 RPM. Just sat and waited letting it idle, just would not go down. Drove home.
2 hours later, I start it. Idle climbs to 1500. I just let it sit and idle. After the supposed 28 seconds, it started to audibly change speed very slight. Slowly, it drops about 100 RPM. About 10-15 seconds later, slowly drops another 100 or so. Slowly slowly, until, after a few minutes total, it finally drops almost exactly to 1000. Stays there and idles smooth as silk, I mean smooth. I cant believe what I'm seeing and hearing. Put in drive, back in neutral, perfect. So, I shut it off.
About an hour later, I start it, drive to the store again. Still perfect in every way. Spent about an hour or so in the store. Started it, 1500 RPM again. And, all the way home, pulled in garage, would not go down, just sat at 1500.
Started up this morning, idled @ 1500 RPM.
Went to store. Then decided to drive around a bit to see if it would drop. Drive about 5 miles, stopped. Idle still 1500 RPM. Just sat and waited letting it idle, just would not go down. Drove home.
2 hours later, I start it. Idle climbs to 1500. I just let it sit and idle. After the supposed 28 seconds, it started to audibly change speed very slight. Slowly, it drops about 100 RPM. About 10-15 seconds later, slowly drops another 100 or so. Slowly slowly, until, after a few minutes total, it finally drops almost exactly to 1000. Stays there and idles smooth as silk, I mean smooth. I cant believe what I'm seeing and hearing. Put in drive, back in neutral, perfect. So, I shut it off.
About an hour later, I start it, drive to the store again. Still perfect in every way. Spent about an hour or so in the store. Started it, 1500 RPM again. And, all the way home, pulled in garage, would not go down, just sat at 1500.
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Joined: Oct 2008
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From: Bellingham, Wa
1989 190e
This is just a thought, try pulling your fuel pump relay and cleaning the contacts with electrical cleaner. Then apply some dielectric grease to each one. Could help....
You can actually do this with all the sensors/plugs in your engine compartment. You never know - you could get lucky
You can actually do this with all the sensors/plugs in your engine compartment. You never know - you could get lucky
