(87 gtu) well after replacing and port matching my intake mani the car was running really well then while accelerating once it seems to loose all power and then it started to spit and sputter and start hard. and had bad idle surge. so i tore the intake mani back apart to find out i blew a omp line. i fixed it and now the car has fuel but no spark from leading coil, and a yellow or weak spark from trailing, i cant figure it out the car wont start, i get plenty of fuel i can smell it while cranking

checked voltage at coil got 12 volts
replaced coil and ign with known good one
replaced afm with known good one
all fuses check out good


i have searched 20+ threads and did everything recommend to try and fix this i cant figure it out, im very frustrated.

 

How are you checking spark on leading? The plugs may be so fouled now that they arent lighting off.

 

i used 4 diff plugs, i am grounding them out on the engine while my roomie cranks it

 

So when you are checking spark, you arent pulling any fuses or relays?

 

no i dont pull any, i tried with the afm unplugged and plugged in with no change

 

Sounds like something that could occur if the main ground on the UIM has seen better days. Definitely something that could occur when the UIM is removed repeatedly. Also, the Green/Yellow wire at the leading coil needs to have 5 volts on it w/key to on and then see 0 volts as the main pulley is turned. This shift from 5 volts to 0 volts is constant and this needs to occur for the coil to fire properly. If not then the CAS, ECU, and or grounding is problematic.

 

the ground under the uim has a added 4g connector on it, well i got the car to start up but the spark on the leading coil is weak still

 

If the contact point is poor that's all that's necessary to create a problem as all else would be immaterial. Perhaps a new bolt and a thorough cleaning of the thread is in order in addition to checking the other relevant components.