Engine/Transmission (1994 - 1998) Blow by, mechanic says #3 cylinder doa

[wrichards]

1998 12 valve 134k, 3500 work truck. Engine running rough, has a lot of steam pulsing out of fill when hot. Mechanic says #3 cylinder bad because when he cracks that injector engine remains the same unlike cracking any other injector engine runs worse. Valves have never been adjusted, injectors original, vaccum pump original. Where would you start. My fear is dumping money into engine with bad cylinder. I have owned this truck since it had 50k on the clock and changed oil with amsoil every 3k since so I feel as if it may not be cylinder but am confused why such blow by. thanks

 

[AEdelheit]

Could also be a bad injector or pump issue, id start with a compression test to verify engine condition

 

[Vaughn MacKenzie]

Could be a bad head gasket. Anything odd or unusual happen leading up to it, did it start all of a sudden? Overheat the engine significantly? Were you towing heavy and maybe let your exhaust temperatures get too high?

 

[BIGNASTY]

Only 134k? not very many miles compared to some on site.

 

[Dieseldemon]

Check Compression for sure

 

[PToombs]

And maybe swap that injector with another one and see if the problem changes with the injector or stays with the hole.

 

[GAmes]

I agree thate mileage is way too low to worry about blowby. If you feel the need you can build your own basic manometer for a few dollars. http://www.cumminsforum.com/forum/94-98-powertrain/232645-tool-check-blow.html