94 z28

[anthony m]

hi i have a 94 z28 5.7 runs ok when cold except smells like its dumping fuel after about 1 mile of drivinv it wants to stutter or misfire when pulling off also is it normaL that if i put a noid lite on an injector wire that if the engine is running i get no lite but if i shut engine off and restart i get noid (pulse) this is the same on all injector wires it almost feels like a bad spark plug wire when it stutters but plugs and wires are new any help???? thanks

[ROUDA]

I Have Heard Of An Injecter Getting Clogged. Or A Clog In The Fuel Line .

[corning_d3]

The fuel smell when cold is typical open loop operation. I bet you cut off your catalytic converter, huh. I wouldn't be unplugging injectors and plugging in noid lights with the engine running. Your supposed to disable the fuel system(usually by removing the "Fuel Inj." fuse, which kills power to the fuel pump), install the noid and crank the engine. A flashing noid light is good. It means the PCM is sending the signal to energize the injector. Is your check engine light on?

[anthony m]

Originally Posted by corning_d3

The fuel smell when cold is typical open loop operation. I bet you cut off your catalytic converter, huh. I wouldn't be unplugging injectors and plugging in noid lights with the engine running. Your supposed to disable the fuel system(usually by removing the "Fuel Inj." fuse, which kills power to the fuel pump), install the noid and crank the engine. A flashing noid light is good. It means the PCM is sending the signal to energize the injector. Is your check engine light on?

hi no check engine lite but i'll have to check if the cat was cleaned out but i dont think so. as i was looking tonite though i did see that the bank 2 o2 wire is patched and may even have melted against the headers so i'll re do the sensor harness and check thatalso the caruns like bad wires when warmed up

[anthony m]

Originally Posted by ROUDA

I Have Heard Of An Injecter Getting Clogged. Or A Clog In The Fuel Line .

the cylinder balance test shows #2 ......no change when turned off w/scanner plug getting spark compression is 105 in cyl 2 thanks for any suggestions,

[anthony m]

Originally Posted by anthony m

the cylinder balance test shows #2 ......no change when turned off w/scanner plug getting spark compression is 105 in cyl 2 thanks for any suggestions,

oops i almost forgot w/scanner hooked up timing at idle fluctuates from 17deg to 21 at idle constantly

[corning_d3]

I'd say pull injector #2 and slap a new one in..

[anthony m]

Originally Posted by corning_d3

I'd say pull injector #2 and slap a new one in..

thanks i already tried that also tried a new pcm (remaN) also should the noid lite get brighter when opening throttle?seems dim when idling w/engine warmed up its 50% brighter when cold after warming up light is pretty dim except when opening throttle then it gets very bright at first crack of the throttle

[corning_d3]

Hmm, i believe the light should stay at the same brightness regardless. I'd start looking around for more chaffed/burnt wiring..

EDIT: Are you sure your battery is up to par? I'd check the voltage at the battery while idling.

[anthony m]

Originally Posted by corning_d3

Hmm, i believe the light should stay at the same brightness regardless. I'd start looking around for more chaffed/burnt wiring..

EDIT: Are you sure your battery is up to par? I'd check the voltage at the battery while idling.

yea battery is good alt putting out 14.15 i know the ground for the injectors on this motor is supplied through the pcm that is why i tried replacing and also i tried checking the pos wire for the inj.and light is bright when i reverse to the neg wire (pos bat terminal to neg terminal on inj.plug )i get a dim pulse like it is not a good ground unless the messed up wire on the o2 sensor as mentioned earlier is causing that i will try to replace the 02 wire tomorrow to see if that helps i would have tried to replace the dist. by now if it wasnt such a big job its behind the water pump unlike my 95 silverado which is on top who the h- - - thought that one up

[corning_d3]

So is number 2 cylinder is the only one giving trouble(dim light)? First thing I'd do is do a resistance check with an ohmmeter on all the injector grounds from the injector to the PCM harness. You shouldn't see anymore than .5 ohms. All injector grounds go to Connector A on the PCM. Here's a pinout:

Injector--------Harness Location
1....................Pin 3
2....................Pin 19
3....................Pin 21
4....................Pin 4
5....................Pin 20
6....................Pin 5
7....................Pin 6
8....................Pin 22

The PCM grounds thru Pins 2 and 18, so make sure the wires there are properly grounded.

After you test all grounds, then move on to the Pink hot wires. There are 2 fuses for the injectors, Fuse 9 is for 2,3,5 and 8. Fuse 10 for 1,4,6 and 7. Check the resistance from each injector to the fuse panel. You shouldn't see anymore than .5 ohms.

If you still haven't pinpointed it, try testing the voltage at both fuel inj. fuses.

[anthony m]

Originally Posted by anthony m

yea battery is good alt putting out 14.15 i know the ground for the injectors on this motor is supplied through the pcm that is why i tried replacing and also i tried checking the pos wire for the inj.and light is bright when i reverse to the neg wire (pos bat terminal to neg terminal on inj.plug )i get a dim pulse like it is not a good ground unless the messed up wire on the o2 sensor as mentioned earlier is causing that i will try to replace the 02 wire tomorrow to see if that helps i would have tried to replace the dist. by now if it wasnt such a big job its behind the water pump unlike my 95 silverado which is on top who the h- - - thought that one up

thanks i'll try that today and i'll let you know this eve thanks again anthony