Did Dodge sometime in the mid 1990's build any Ram trucks that had 5.9 Gas motors (360c.i.d) that under certain driving conditions would basically shut down 2 opposing cylinders, maybe for emissions or to meet MPG requirements
via the ECM. Later on recalling or having dealers attempt to Flash those computers due to chronic problems. My 1998 intermittent drops #8 with no codes and we determined the ECM was from an earlier year. A Auto ECM Guru hooked up to it and said it was one of the old version ECM's that a previous owner must have put in and the ECM was never corrected properly years ago.

We went thru the truck with a fine tooth comb and can't find any issues.
runs fine , then out of no where will drop # 8.

Did Dodge try this like GM did on the early Cadillacs did, only using enough cylinders to motor down the road.

Help! Thanks in Advance

 

Nope. No cylinder shutdown on trucks until about 06.

Have you fixed the plenum? (Read the sticky. )

How many miles on it? Checked the plugs lately?

 

Complete tune up and the plenum issue, also went thru TB.
202k miles 1999 Ram 1500 , Auto. Compression tests wet and dry as well as leak down test too.Ran rich for the 1st tank an now when it's not droping a cyclinder the mixture seems fine. Just passed CA> smog in Sept. Got it in when it was firing on all eight one day.

 

Check plug wire routing. There is a TSB for it in the faq section. (if you have *good* quality wires, not so much of an issue.)

Try swapping injectors on 6 and 8, see if the miss moves.

Beyond that, I would have a look at the crank sensor.....