1990 3.0 MTX backfires

[Bruce M]

Sometimes on startup (cold start up but can happen hot) I get either misfires or backfires. These are not loud and might be mised if your not expecting it. If I shut the engine down and start it up again they often go away. Scanner says CID. so its pointing to the Cam posistion sensor. Will these motors even run with a bad CPS or a faulty CPS? Has anyone had these symptoms before and is tyhe CPS the likly susspect?

 

[SHOtime2511]

if thats what your scanner is saying,id say the CID is a good bet.
id go ahead and reset the ecu and wait for the problem to occor again then check the codes once more.

 

[shobote]

I believe the car will not run at all if the CPS is bad; so probably not due to a bad cps.

 

[AREA 91]

Time to change your CAM sensor.