StevenB L98/LS1

For a year now ive been tracing down a dead missfire. After my intake swap was finally done, the car started to idle like it use to, but now its even worse. Im thinking it's the distributor since the car is surging at idle. I can drive the car and then come to a stop and all is fine for a couple seconds until it starts missing liking crazy. And if your waiting to long it will start surging and eventually die. Or if your moving slow down in a drive thru and stop the idle become unstable and dies.

Ive replaced the distributor about 5 years ago due to the problem of the car surging then, and then 2 years ago 3 injectors went bad and i replaced them and all was fine until a year ago and started doing the same thing. Ive tested the injectors, checked the fuel, checked spark and all seems be fine. Before i replaced my oil sending unit so my gauge would start working the car already had a miss for a few months i noticed the miss became worse though after i installed the sensor., a week after i installed the sensor i had a oil leaking out of the intake, so i did my intake swap and it idles worse than it ever has.

Im stumped trying to trace down this miss that has become worse. The car feels awesome when you stomp on it and drive it, only at idle it missfires and surges. Any ideas before i replace the distributor once again? Even though im getting spark is it possible the distributor is just the cause for all this still?

utilityguy2

iTrader: (1)

Are you sure you don't have low fuel pressure or extremely high at idle? injector can shut down and cause miss. If it was spark, I'd think it would be worse when lugging or full throttle. Sounds more like bad injector but that's just my opinion.

StevenB L98/LS1

I will recheck the injectors, it could be a faulty injector. Feels weird to think its the injector with all the power it has. But another idea came to mind that maybe the magnetic pick up in the distributor could be going bad.

red rock

iTrader: (2)

so your not throwing any codes to help point you in the right direction? Seems strange.

StevenB L98/LS1

No codes, everything sensor wise is functioning.

red rock

iTrader: (2)

No codes? Then maybe a bad ECM, or ground to the ECM. Bad grounds can cause a whole host of problems.

StevenB L98/LS1

I think its going to be fuel or distributor related, the ecm wont throw codes for those 2. Mainly the only thing the ecm really detects is egr on our cars, sometimes sensors go bad and the ecm will not give you a code. Im starting to think injector 4 might be the culprit but im not sure, i get intermittent ohms on that injector. But tested during hot its consistent, but cold its not. and the car has a hard time keeping a high rpm on cold starts, its already hitting 700 rpm on cold starts.

red rock

iTrader: (2)

K

StevenB L98/LS1

Injector 4 keeps giving me 15.1 and then 14.7 then sometimes 16.7. Why do i keep getting different reading off the injector? Is it getting enough fuel but the pulse is inconsistant while running?