hi everyone, i have a 91 trans am 5.0l tpi that i stuck a cam in last week.nothing wild just a 209 213 duration and 440 476 lift at the valves with 1.6 roller rockers.i also have a fastchip custom prom to remap all the ignition and fuel.the problem i'm having is when i start the car it runs well sometimes,most of the time the second i put it in drive the tach goes crazy sometimes jumping between 1000 and 2000 rpm back and forth like it's spring loaded.the engine wants to stall and misses when this happens.it's somewhat drivable but it bucks a lot when it's up to speed.i ohmed out the coil warrantied my distributor yesterday and it drove fine all afternoon.this morning the problems returned,it wasn't the cam.but i'm thinking while the intake was off and the harness's were moved around i may have pinched or broke something.especially the p-side where that fat harness is by the valve cover.this thing feels like every cylinder is leaking spark.any help and suggestions would be much appreciated

 

Put your stock chip back in and see whats happens. Thats not a huge cam and the stock chip should be fine NOW to see if the problem is cured. Its that is the problem the chip is bad. Once you get the new chip back then you can start tuning again. Not saying stock is optimal but it may help you better find your problem

 

yea i tried that too,i only put the new prom in 2 days ago,the car has been missing since i finished the cam swap last week.the prom actually helped smooth it's idle out some