Spark plug fouling

[twobjshelbys]

Originally Posted by jhv48

Call roush. Their early IR engines were known to have FI gremlins.

Indeed. If you have the Accel DFI controller you're in for a ride... It took months, shipping the car to Roush (which accomplished nothing) and finally finding an Accel trained tuner that knew how to adjust all the tables.

If you are at high altitude the early tunes did NOT populate the altitude compensation table. The system uses the MAF sensor on power up to estimate the altitude and make fuel trim compensations. Mine ran incredibly rich all the time as it sounds like yours may be. The system DID work correctly at say below 3000' but failed miserably at our 5800 feet where I was and got really bad in Estes Park at 7000ish... Roush admitted they hadn't completed the tuning process at altitude but never came through with anything to fix it.

If it is the Accel system you will need to acquire their "dongle" and software. You will need the "advanced" system that opens up all of the tables. I found the hardware at Jegs but that was years ago... That particular DFI system is perhaps the most complicated you can get but it is also able to control things rather precisely. It does no self-tuning.