I was spraying for almost a year with a Zex Dry 55 & 75 shot when all of a sudden I was having a really bad misfire/hesitation problem when I would start spraying around 3500-4500 rpm at full throttle. Ignition consisted of Iridium plugs, MSD wires, Cap and Exteral Coil.This would only happen under spray, NA it would pull up to 7k with no problems-part throttle and WOT. My RPM tach stopped working as well and was told when that happens its the ICM. Switched out the ICM everything was fine for a few days but the tach went dead again same misfire sh*t, ocasionally would get check engine light, code 43 "Fuel System." Installed a Walbro 255 LPH pump, B&M FPR, RC 310s but to no avail. Ditched the nitrous and went boost. Crome Pro on 8.7 psi, new NGK BKR7E's gapped to .26, DSM 450s with inline 10watt, 10 Ohm resistors and at 4500 and up same bad misfire/hesitation, no check engine light though. Took the cap off and found the screw that holds the rotor in came loose and caused havoc inside the dizzy, broke all the teath on the inside of the dizzy. Replaced the dizzy with a used one of a buddies car and it ran like a champ no problems, RPM tach all good as well for a few days. Tach went dead again and hesitation returned but not as bad as before. Both old and used dizzy were OBD2. Engine wire harness is OBD2 of course. Replaced the used dizzy with a brand new one (OBD2), ditched the MSD stuff and put in some stock used plug wires I had. Tach back again, no hesitation everything good again for a few days. Now slight hesitation is back sporadically under WOT 4500 to about 5700-6000 and tach is dead again. What could be frying the ICMs this makes 3!! WTF any help will be greatly appreciated. No check engine lights.

Someone suggested to check the tps but I dont know how with my 6$ voltometer


99 B20, p75 ecu, obd2-obd1 harness

Sorry for the book report


Modified by blazin99si at 7:15 AM 5/1/2006

 

ttt

 

No one?