snakepliskin

Hello,

Question for the engine gurus...

My motor seems to be fouling the #4 plug to point that the car will only run on three cylinders. This is the second time that this has happened. First time my mechanic said that the #4 fuel injector was leaking/dripping into the cylinder, thus causing the foul. He replaced the injector and plugs and car ran well for about a month of driving. Last night, it happened again...Sputtered home, pulled the plugs, 1-3 looked fine, but #4 was toasted. Cleaned it on a wire wheel and some fine sandpaper, replaced and car ran well... Until I exited the highway this morning after my 15 mile drive from home to the office. As soon as I slowed to exit, she started sputtering.

Just some background on the car... Blew head gasket a few month back after "Ingesting water through intake" (remember me?) and had full top-end work done on car, including valve job, and cap, rotor, wires and plugs. She's an 84 na, and REALLY ran awesome until this fouling problem started.

Any ideas would be appreciated.

Thanks

Mike
Atlanta

jsonnen

Could be a small hole or crack in the piston, i had the same problem on a Bmw a couple of years ago! Get someone with a beroscope to see if theres a hole in your piston! Good luck

SoCal Driver

Cracked head.

special tool

Yeah, dude - head is cracked by #4.

MHT

what do the deposits on the plug look like? Is the plug wet, black and does it smell of fuel? Are the deposits gray and do they form a clump? If the fouling is fuel then you may have a problem with #4 injector or have a really large vac. leak, maybe the intake gasket on # 4 cyl. has blown out. I know it sounds strange but you can get a mixture thats too lean to burn and leave fuel deposits on the plug. If the deposits are solid, clumpy and gray then you have a problem, that would be oil and that's not a good thing, best case would be valve guides or seals, worst would be cracked piston, broken rings or really badly damaged cyl. walls. Good luck

Jim @ EuroWerks

Ck compression maybe the water bent #4 rod. Incomplete combustion don't ya know.