Fixed It - Backfire, Misfire, Rough Running 348tb

Hey All,

RE: 1992 Ferrari 348TB

Just wanted to give an update that I fixed my recent Rough-Running and 5-8 bank engine cut-out issues.

My car was back-firing and popping and hesitating at 4000-5000 rpms and the 5-8 check engine light was coming on and off.

After researching all of the articles on this board I determined the most common problem would be the speed/crank sensor or connection to the sensor.

This weekend I jacked up the car and removed the bat shield to reveal the speed sensors just below the main belts.

Sure enough, I pealed back the rubber boot on the 5-8 bank speed/crank sensor and the wires were seperating and barely hanging on, thus causing the misfire and check engine light to come on when the sensor wiring would short out.

As a temporary fix I resoldered the wiring into the connector plug until I can hopefully track down a new wiring harness.

Started her up and she redlines smooth as could be now.

Hope this helps anyone out there with the same problem.

This message board is awesome as I now feel more confident owning and working on this Ferrari with the help of others going through the same problems.

I don't remember all the posts I used to diagnose the problem, but many thaks to all!!!!!!!!

Nick
Racine, Wisconsin