420A Bad misfire, cylinder 1 dead

[Karmah]

Hey guys, been messing with my girlfriend's car for a while now. Still can't trace this back to the cause. Cylinder 1 is completely dead; when you pull the spark plug wire out of the cylinder when it's running, no sound is changed at all. We've replaced the spark plugs, wires, coil pack, did timing on it which is dead on with new components, compression tested 180-190 on all cylinders. Not sure what else to do to test for anything else. Any opinions? Car has about 145k miles and is a 1998.

 

[Dsmkauai]

There's no codes or anything? Could be a cam or crank sensor issue.

 

[Karmah]

Just cylinder 1 misfire code.

 

[ThunderChild]

Injector? If you have compression, and you know you're getting spark, fuel is the only thing left.

 

[Karmah]

Replaced all of the injectors, forgot to mention that

 

[OGDSM1989]

Are you getting voltage at the injector clip ? Could be a bad injector clip / wiring

 

[Karmah]

Yes, used a noid light. I believe it is what it's called.

 

[OGDSM1989]

So Voltage at injector, new injectors, coil , plugs and wires are also new ...... and you check for spark on cylinder one ? Ignition control module ?

 

[Karmah]

Yes, but just by seeing how much comes out when the plug is pulled. Looks the same as the rest, so I'm assuming it has spark. I'm just dumbfounded.

 

[OGDSM1989]

I would get a spark tester ... to be sure that it is sparking ..... I know you said you have new injectors but I would swap injector 1 to cylinder 3 and see if the misfire moves that is real simple you could even move plugs around and see what happens .... even a weak spark will cause a misfire.

If the miss fire doesnt move then its either mechanical or in the wire/electronic and atleast you can start to narrow them down

 

[Boost-Junkie]

Put a vacuum gauge on it to look for a valve issue. if you have fuel spark and compression only thing left is air.

 

[ThunderChild]

Put a vacuum gauge on it to look for a valve issue. if you have fuel spark and compression only thing left is air.

Good idea, you could check for spit roller-followers. Pull the valve cover and make sure you don't have any missing valve train pieces