I was just informed that the distributor is automatically set...Therefore the timing can not be off.. Is this true?
05-09-2013 05:50 AM
Yes, the timing is controlled by the pcm (computer).
05-09-2013 02:22 PM
The timing can be off. It all depends on all the inputs being within tolerance to the ECU. It then does the math and computes timing and fuel mixture. If everything is right the timing will be within specs.
05-09-2013 03:57 PM
First off, what year and which engine?
Older Jeeps still use a distributor that can be adjusted. Starting in around 2001 they went to a distributorless ignition system that is fully controlled by the computer. If you have that you don't really have to worry about setting or checking the timing.
05-15-2013 11:05 PM
It's a 98. 4.0
05-15-2013 11:11 PM
Does the ecu have anything to do with the crankshaft positioning sensor?
05-16-2013 10:59 AM
It should have a distributor. I don't know if it has mechanical advance or if the ECU takes care of the advance or if it's a hybrid of the two. The CPS will tell the computer which injectors to fire and when but the distributor will direct the spark to the right plug.
I don't think the distributor will be fixed and set, even if the ECU completely controls the timing. It is possible for the base timing to be off and the distributor needs to be adjusted. If you grab a Haynes or Chilton manual from the local parts store and borrow/rent a timing light you should be able to figure out how to make sure it's set right.
05-17-2013 01:28 PM
'98 distributer just directs the spark to the correct plug. Timing is done by the ECU.
05-19-2013 11:05 AM
Ok thanks guys..I'm hoping this is the reason it hesitates bogs out and backfires somewhat