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rpmdiag, Tech and Instructor
Category: Mercury
Satisfied Customers: 8073
Experience:  Since 1975
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Mercury Topaz: My 94 mercury topaz 2.3 idles highs as soon

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My 94 mercury topaz 2.3 idles highs as soon as it starts and doesnt drop. I already cleaned the throtle body and replaced colant temp sensor next to the upper raddiator hose. I also fixed two vacuum leaks and it still the same and only getting worse. What is the problem?

rpmdiag :

Thanks for your question. Sorry you're having car problems. If I go off line, just leave a message and I'll be right back. DO NOT leave feedback yet. The idle motor is probably dirty or defective. Take it off and clean it first, then re-train it too. Thanks, Ron

rpmdiag :

Relearn procedure:

Disconnect both battery cables for 20 minutes and touch the 2 cable ends together for 10 seconds. After the 20 minutes has expired, re-connect the cables and start and drive vehicle for about 15 minutes under a variety of conditions such as idle, cruise and wide open throttle, to do a complete re-learn of the rest of the computer system.


rpmdiag :

Please click on the appropriate “positive button” to Rate My Answer AFTER you have followed OR agreed with my suggestions. If you have more questions, then click on the “CONTINUE CONVERSATION” button PRIOR to rating me. Please remember to only rate my answer when you are 100% satisfied. IF you feel the need to click either "Helped a little" or "I expected more", please stop and reply to me via the REPLY or CONTINUE CONVERSATION. If you click on either of those two buttons, you will be leaving NEGATIVE FEEDBACK for me that hurts my reputation.

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Customer: I already cleaned that and the engine light is not on. It runs high in drive to the throtle is constanly wide open.
rpmdiag :

Then the idle motor is probably defective. You will need to do the re-learn AGAIN with the new idle motor too. Thanks, Ron

Customer: I already cleaned that and the engine light is not on. It runs high+ in drive to the throtle is constanly wide open.
rpmdiag :

OK, so you have done ALL my suggestions including the re-learn procedure. That only leaves the idle motor to be bad then and it needs to be replaced. Please don't forget to rate me as high as you see fit and I can still assist you afterwards too if you need me. Thanks again, Ron

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