Car revs high when driving
I have a 1993 Olds Cutlas Supreme 3.1. When car warms up, car revs high, about 3000 rpms at 65 mph. Normally runs about 2200 at this speed. Have tried to pull codes but am getting no codes. Check engine is on most of time but was before this problem started. We have cleaned the throttle body several times. Seems to help for a while but then does same thing again. Any suggestions?
12 Answers
migration_judge_roy answered 10 years ago
think the ambient sensor is not workin' right....let me investigate~
Thanks judge_roy. Do you think I should change this sensor or wait while you investigate further?
migration_judge_roy answered 10 years ago
...well let's think about it some more...this sensor is what sets the air/fuel mix when hot or cold....but now I believe based on your problem description that it's the throttle position sensor have been burned because the sensor that I specified was for the thermostat on the top of your mirror, sometimes the computer shares this info sometimes there are two sensors, but if it is temperature related has to be a thermal sensor....runs good hot, runs good not so hot, runs not so hot when cold....etc...will price out a TPS as these DO wear out and issue erratic behavior~.....also will pull a check engine lite and code as well~
migration_judge_roy answered 10 years ago
the throttle postion sensor...if these things are givin' bogus instructions to the computer, lordy how...the gas smilege will go kaput~
It runs good when cold and warm, not so good once it reaches temperature. Husband says it seems like it drops out of overdrive when it is running bad. When running bad, if you take your foot off the gas pedal, rpms drop to about 1000. As soon as you put it back on, starts going up again. Trying to give as many details as possible for you.
migration_judge_roy answered 10 years ago
it's like NOT expensive a part....couple of burritos cost is all~
migration_judge_roy answered 10 years ago
...telling you it's worth the risk...if nothing else the cost of saved gasoline~
I changed the TPS and it is still doing the same thing. The battery was disconnected for at least 5 minutes then reconnected so the system could relearn. This was done this past Sunday and have been driving it every day since. Would this correct right away or would it take time to "relearn"?
migration_judge_roy answered 10 years ago
high revs---computer still thinks it is cold and need more to keep it running under cold conditions...when it warms up....well should know by the temp sensor and feather it back to 700-900 rpm~ will have to find your electrical schematic to find out if the ambient sensor or the one in your coolant (base of the radiator) sensor is responsible for setting the RPM to the prevailing conditions.....also could just be a vacuum leak as ole' butyl rubber tends to crack. you could check for these leaks with an unlit propane torch or a flammable can of brake cleaner...if you can hear hissing...that's your leak~ as far as relearning, it cannot learn to not have a vacuum leak anymore~
migration_judge_roy answered 10 years ago
replace those butyl black leakers with silicone vacuum hoses~