Been heaps busy with work and haven't had a chance to really dig into it and start troubleshooting but im thinking its due to possibly a failed coilpack, spark plug or injectors.

Symptoms:

Intermittent (started months ago as rarely but has started being more frequent) vibrations felt thru steering wheel and gearstick

When the vibrations starts, it hestitates and loses power. Sometimes slowly accelerating, it would return back to normal.

The exhaust also sounds like a boxer engine when accelerating and its really rich, spitting fuel out of the exhaust tip and a strong scent can be smelt.

RPM doesn't seem to be affected at idle, it misses a few times but nothing drastic as if it was going to stall

No CEL, but im not sure if the HKS V-pro is masking it or not

Mods:

HKS single turbo kit
HKS V-pro V3.2
Walbro fuel pump
DW 600CC injectors
Fujitsubo exhaust

At first i thought it could be a cracked engine mount due to the vibrations but the fault is intermittent, so highly unlikely its a mount. Also doubt its a flywheel/clultch but i could be wrong.

So im thinking its ignition related as i think it started when i had a batch of fuel one day. I have since replaced the spark plugs when that happened.


Thanks in advance

 

Start the car and let it idle. Start un-plugging the connectors on the coil packs one at a time. If you unplug a coil pack and the idle gets worse plug that one back in and move to the next. Keep doing this until you unplug a coil pack and the idle does not change. That will be bad cylinder bank. Try swapping that coil pack with one of the known working coil packs. If the dead cylinder moves with the coil pack then you found your issue. If not, do the same thing with a known working spark plug. If the dead cylinder moves with the sparkplug then you found your issue. If the dead cylinder does not chase the coil pack or the sparkplug it’s going to be expensive.

 

You're losing spark on one or more cylinders... if it's accelerating that 'slowly' it could be a whole bank. I lost a coil pack once and it was still very drivable... but losing a whole bank would def. make acceleration slow. Since you have an Fcon I'll bet it's an electrical issue.

 

Excellent tips guys. Will get into it soon and post the outcome.

When you say Since you have an Fcon I'll bet it's an electical issue do you mean a bad ground or faulty sensor?

 

I think he means bad connection. Failed crimp or solder joint.

 

Just an update, seems like my coilpacks are OK. There was quite alot of oil in the 3rd sparkplug well. Seems like the fault moves when we moved the injectors so looks like we will be needing a new one.

 

glad to hear you made some progress on the issue