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Engine idling at 2K rpm when warmed up; locating the Idle Speed Control Motor
Topic Started: Oct 29 2017, 01:18 PM (171 Views)
ScottAY
Fresh Fish
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Hello everyone. I'm a little nervous posting here. So many of you are so very good at diagnostics. So, I've a '98 Metro, 3 cyl. 190K miles. Good compression, runs nicely. I put a new fuel injector in the throttle body about 3 years. Ran fine. About a month ago the engine began to run up to 2K and higher rpms. I've checked for air leaks in hoses; can't find any. My thinking now turns to the idle speed control motor. I infer this throttle body has an ISC motor, not an IAC valve. Is this correct? I don't know how to locate the ISC motor. I'm going to try to attach an image of the passenger side of the throttle body and an image of the fire wall just back of the throttle body. Can any of you tell me which of these components in the ISC motor? I very much appreciate your help. Scott
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Edited by ScottAY, Oct 29 2017, 01:22 PM.
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ScottAY
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I think that I should have said that the engine runs up to 2K rpm and higher when warmed up and at idle. Sorry.
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freegeo
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The black component attached to the back of the throttle body is the isc. The motor is inside the isc. I am at work or I would post a picture of it. Is your throttle cable possibly keeping the throttle plate from closing?
Edited by freegeo, Oct 29 2017, 01:58 PM.
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freegeo
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You mentioned you checked for vacuum leaks. Double check the vacuum lines, especially the one going too the brake booster.
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ptcapboy


you may also try feeling the coolant hoses going into the throttle body and making sure they are warm when the engine is warm and I wouldn't feel nervous about posting we're here to help and the only "dumb question" is an unasked one-
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ScottAY
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Well, thanks Freegeo and Ptcapboy. Your suggestions are excellent: check vacuum lines (esp. brake booster) and temp of coolant into the t. body; I'll do these things. I think I've the ISC located, Freegeo. Thanks. I'll attach an image of what I think is the ISC. Many thanks, and I'll get back when I check some things out. Thanks again.
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freegeo
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Yes that is the ISC.
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