Idle Control Computer/Maybe Fuel Pump?
Thread Starter
Newbie
Joined: Apr 2003
Posts: 8
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From: Hartland, WI
1988 BMW 325is
Idle Control Computer/Maybe Fuel Pump?
Okay, first off, 1995 E420. The car has been giving me trouble and the only answer I have gotten from the mechanic is the idle control computer for $1k, I'm also not convinced he is correct. So I want to be sure before I shell out the cash and find out the problem is still there and he says ahh well guess that wasn't it (and doesn't refund the money).
The car has been having trouble starting. There seems to be a problem at the rear fuel pump relay. When the car doesn't start, it can usually be started by going to the relay and holding it down (I opened it up). Replacing the relay has no affect. Sometimes the relay makes a chattering noise and instead of clicking closed it goes between open and closed (cause that noise). Sometimes the check engine light comes on and the mechanic said this was the idle control computer. I inspected the computer and nothing seems obviously burnt out or anything. The mechanic has never seen it when it makes the chattering noise, only when the check engine light is on. Somehow the car refuses to cooperate and anytime I try to bring it in, it stops doing that and switches to the check engine or just decides to work. I've spent a bunch getting unreliable diagnostics so far...
So any opinions? Any insight would be appreciated. Could this be the idle computer? What about just the fuel pump? Is it possible this is failing in such away to get this mixed signal to the computer? Thanks
Toby
The car has been having trouble starting. There seems to be a problem at the rear fuel pump relay. When the car doesn't start, it can usually be started by going to the relay and holding it down (I opened it up). Replacing the relay has no affect. Sometimes the relay makes a chattering noise and instead of clicking closed it goes between open and closed (cause that noise). Sometimes the check engine light comes on and the mechanic said this was the idle control computer. I inspected the computer and nothing seems obviously burnt out or anything. The mechanic has never seen it when it makes the chattering noise, only when the check engine light is on. Somehow the car refuses to cooperate and anytime I try to bring it in, it stops doing that and switches to the check engine or just decides to work. I've spent a bunch getting unreliable diagnostics so far...
So any opinions? Any insight would be appreciated. Could this be the idle computer? What about just the fuel pump? Is it possible this is failing in such away to get this mixed signal to the computer? Thanks
Toby
Newbie
Joined: Nov 2002
Posts: 10
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From: Reykjavik, Iceland
Mercedes GL Pewter w. offroad package and a PE launch Edit.
The idle computer
Hello Toby,
I also have this problem with my 1995 E420 but not with the relay and I live in europe so we dont have check engine lights. I took it to the dealer and had it plugged in and they told it was the injection actuator wich is the idle computer. I have problems starting (sometimes it wont start at all) and sometimes when I put it in R or D the RPM goes up and down but its ok in N and P. The dealer told me these things break down very often and I sholdnt be surprised specially in the 4.2 V8.
Huginn
I also have this problem with my 1995 E420 but not with the relay and I live in europe so we dont have check engine lights. I took it to the dealer and had it plugged in and they told it was the injection actuator wich is the idle computer. I have problems starting (sometimes it wont start at all) and sometimes when I put it in R or D the RPM goes up and down but its ok in N and P. The dealer told me these things break down very often and I sholdnt be surprised specially in the 4.2 V8.
Huginn
