Cylinder Not Firing

[bauer.gtr]

Ive got a rb26dett engine that shakes on idle, and ive been told by a number of people that im misfiring. I unplugged the coilpacks one at a time and the engine responded by shuddering untill i unplugged the coil on the cylinder closest to the firewall. The engine ran no differently if that coil was disconnected or not. I swapped it with a different coil and it didnt solve it, so the coils are good. I checked the wiring harness and grounds, they seemed ok as well. Whats wrong here? I dont know what else to check. please help! can post pics

thanks in advance.

1991 r32 gtr 145,000 kms

stock, other than 3'' exhaust and turb timer

[blind_elk]

If the coils are good, then swap the spark plugs around, then repeat the coil test. And do the same sort of test on the injectors.

[NZM.031]

and check compression while the plugs are out...

another thing to check is for vacuum leaks... split breather hoses etc.. the engine only has vacuum at idle and thats when these leaks are present... at driving and boosting, these leaks may not appear.

[bauer.gtr]

thanks, I pulled the plug out of the bad cylinder and it was oily.. i then swapped it with another plug and STILL had the same problem on the same cylinder. so I'm getting spark, ill try swapping the injectors within the hour here...

I did a boost leak test last week and found a big one on the turbo outlet piping. Threw a new gasket in and was good to go, but ill look into possible vacuum leaks. ill try to get the compression looked at as well.

Thanks for the responses, i am a new member, but im an old guest! this is a great forum.

[DuFFR32]

Im currently having the same problem except ive narrowed mine down to cylinder no 3, im testing coilpacks atm now going to do injector test. if they are good then ive def busted a piston and or cylinder and im up for a new engine.

But the weird thing is, my car drives fine, yeah it shudders on idle but it boosts fine so yeah i thought if i had a busted piston it would be making unhappy noises.

[08yannch]

oily spark plug... sounds like the injector to me. might just need a clean