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View Full Version : Help with the ICV, pulling and cleaning



brendanm
01-19-2007, 07:27 PM
I've got a issue starting and idling, the car won't start very easily, needs a lot of gas, and then won't idle very well, wants to stall out. It runs fine once it's warmed up, or at least seems too, although the idle still seems low at around 500rpm. No engine check light, and no engine fault codes. From my readings and suggestions from this forum, I'm going to start by pulling the ICV and cleaning it (possibly replacing it, but at $115 cleaning would be a first choice, provided it works).

Any help you all could give me in how to go about pulling the ICV and cleaning it would be appreciated. I've a diagram from the part website, but it being the weekend, I won't be able to get my hands on a Bentley manual for some weeks, certainly not before I take the car in for a tune up. I'm assuming the ICV is the part labeled #17 "L-Shaped Idle Regulating Valve".

I'd like to narrow the issue, if not solve it before this coming Thursday, when I've got an appointment with a highly recommended but expensive mechanic.

Jeff in MN
01-19-2007, 08:02 PM
it with some carb cleaner from both ends. Look inside to see that it clean and you're good to go.
However, before you finish, besure to check the continuity on your Throttle Position Sensor. At closed throttle you should get zero ohms between two of the connections on the TPS. If you are reading between 1 and 5 ohms, you will have problems like you described. I chased my idle problems on my M30engine for months before I noticed I had slight resistance in the switch. Basically, if you are getting 1-5 ohms, the computer does not know your throttle plate is shut and doesn't know what to do.
Good luck.

Blitzkrieg Bob
01-19-2007, 08:02 PM
buy a can of throttle body cleaner, and spary the inside from both ends and see if the rotor moves as you clean it.

for good luck, you can also clean the throttle body too.

Randell
01-21-2007, 01:55 AM
At closed throttle you should get zero ohms between two of the connections on the TPS. If you are reading between 1 and 5 ohms, you will have problems like you described. I chased my idle problems on my M30engine for months before I noticed I had slight resistance in the switch. Basically, if you are getting 1-5 ohms, the computer does not know your throttle plate is shut and doesn't know what to do.
Good luck.

i've just taken my AFM and ICV off to douse in carb cleaner, while i'm waiting for it to dry i tested my TPS... at idle with the ignition on A/C i get 2.5 ohms on posts 4 and 6, anything off idle gives me 0 ohms on 4 and 6 and 0 ohms on 4 and 5... even full throttle shows no resistance between 4 and 5... no voltage on anything, despite the bentley saying there should be voltage.?

am i doing something wrong or is my TPS stuffed? i have a so-so idle at the moment, particularly when first starting the car, though the number 13 hose in the diagram above was very loose, hopefully there was a vacuum leak there