van frank

my 1993 16v i prelude is acting up. had it 4 years no probs apart from having the distributor changed just after i got it.















once its warmed up the tickover drops too low and nearly cuts out then comes back up again to a normal level an then is fine until I stop again. It normally happens as am dumping the clutch to put into neutral or first or just stopped at junction etc..the clutch is fully depressed or its in neutral...then a few minutes of driving later the engine management light comes on...weird..theres no real loss of power but it doesnt seem to be running quite as smooth as it has done.















it has a small hole in the rear section of the exhaust pipe, not sure if this would do it? Think its not running as smooth because of pipe but wouldnt have thought it would make problem with tickover do you think? It has been service 6 months ago...any ideas what it could be?

russ.gower@btinternet.com

Sounds like an idling problem. Try replacing the idle speed sensor. You can test to see if it works or not by parking the car up running after its warmed up and unplugging the sensor and if the engines revs change then it is working but could be an itermittant fault. If unplugging makes no difference then its gone completely. The car will run without it but will do what you have discribed. Get a new one or second hand off ebay and try it.















It definately sounds like an idling problem. There are other things it could be; make sure simple things like air filters are clean and air intake hoses are not blocked. Check the throttle body and clean out with carb cleaner if dirty. If you have an EGR system check all of the pipes, check vacuum pipes for leaks as well. If you have a charcoal canister for helping with emmisions, make sure pipes leading to and from are unblocked and working ok - don't think this will make a difference but worth doing anyway. Good luck















PS can't see a small hole in the exhaust causing this problem really. You can try a temp repair and see if it helps, then you will know but I very much doubt it.

saturnine

check the engine light error code, you can do that yourself. i have a 93 civic and the way you do that is to locate the ecu/jumper wire...should be by the passenger frount wheel well. there should be two plugs, find the one with 2 wires, and with the car off, stick a piece of wire into the plug (to cause a short circuit)















turn the key to 'on', but don't start the car. the CEL will come on but then start to flash. short flashes are single digits, long ones are 10's. if there's just one error the code will just repeat itself, if there's more than one it'll go thru them all then repeat itself.















if you have the service manual for your car the error codes should be in there, as well as a troubleshooting flowchart for each error.















to check your error code: reset the ecu afterwards (pull battery's neg cable or the ECU fuse), get the CEL to come on, and repeat the procedure.