: Engine Miss comes and goes

07-30-12, 08:11 PM
Hi I have an 89 that developed a distinct miss, that I have not been able to track down. Sometimes it misses and sometimes it doesn't. Of course, if you try to check the engine, it runs on all 8 cylinders. I have replaced the plugs and plug wires and have suspected an injector but haven't been able to diagnose anything at all. Has anyone else had a problem of this sort? It is bad enough that you don't want to drive it because it will start missing. It does not happen reliably enough to have a relationship to how long the engine has been running, engine temp or speed. There are no codes showing.


07-31-12, 11:04 AM
First thing to check is that all the connectors to the injectors are fully seated. Make sure by pulling on all of them. Do you have a factory service manual? With the manual you can short out each injector to help isolate the cylinder affected.