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Radioadix
07-09-2013, 08:16 AM
A friend and I recently picked up a 93 twinturbo. This is a current list of what has been done to the car thus far:
Battery
Spark Plugs
UIM Gasket
Injectors
PTU Ignition
Fuel Filter
Clutch Slave Cyl
Clutch Cables
Clutch Master Cyl
Compression test confirmed 170+ each cylinder.
Grounding kit

At this time, Cylinder 5 will not fire. We have used a test plug and confirmed that there is spark. We have checked the voltage to each line. the plug is wet with gas when removed, we have swapped the coil pack with a cylinder that is for sure firing. The next step we are about to take is to replace the entire wiring harness just to eliminate that as a possibility but wanted to check on here to see if anyone else has experienced anything like this and what possible fixes you guys can offer. Any help is appreciated. Thanks in advance.

typhoonslippery
07-09-2013, 08:44 AM
did you try replacing the vg30 ? I hear they are usually the issue


injector stuck open ?

Radioadix
07-09-2013, 08:51 AM
I guess your a 240 guy.. lol

The injectors are all brand new.

typhoonslippery
07-09-2013, 08:54 AM
sorta

I remember working on a few of them and the coil pack harnesses were always brittle and had cracks as well as the coil packs themselves were always needing to be replaced like in a ca18det engine.

New injectors don't always mean 100% ... they can be stuck

Radioadix
07-09-2013, 08:56 AM
We swamped the coil pack for cylinder 1 which is 100% for sure working. and still got nothing although with a test plug running off of cylinder 5's coil pack and - we got spark. We also replaced the plug in that cylinder yesterday and its still not firing.

Radioadix
07-09-2013, 08:57 AM
We have also checked the voltage on each line at the clip for the coil pack

double_R
07-09-2013, 09:18 AM
Where did you get the injectors from? I had to replace my injectors before even if I got em brand new.

PoorMans180SX
07-09-2013, 09:21 AM
Check compression on that cylinder. I had a problem exactly like this. Turned out compression was 90psi on that cylinder. Bye bye VG30, hello 1JZ...

Radioadix
07-09-2013, 09:26 AM
Injectors are from advance auto parts - and the compression check has been done - 170+ on each cylinder.

Hopefully we do not have to replace the injectors - that was not a fun job removing the intake.

double_R
07-09-2013, 09:34 AM
Swap your injector with another working one and see what happens. Could be the harness and hopefully its fixed when you replace it.

double_R
07-09-2013, 10:03 AM
Ohm test the injector also.

jr_ss
07-09-2013, 11:30 AM
Why don't you put a noid light on the injector clip to see if it's even getting signal?

JeeBus
07-09-2013, 08:54 PM
injector stuck open or pinched seal.

Both will flood that cylinder and keep it from firing, hence why the plug on that cylinder is wet.