OBD1 code 94

[westcoasttowing]

My 1995 3500HD has a gnarly misfire. OK i just used a snap on scan tool. It's giving me an code 94.
Now what?

[DmaxMaverick]

DTC 94 is a cylinder balance issue with cylinder #4. Check that fuel injector line connections are tight with no leaks. If it appears good, then try swapping that injector with another (preferably on the opposite bank), to see if the problem follows the injector, or stays with the cylinder.

[westcoasttowing]

I went ahead and installed all new upgraded marine injectors with new fuel lines. Same problem. Idles fine but when I rev it there is a bad misfire.

[HeavyChevy95]

'95 model-

DTC 94 Cylinder Balance Fault #5 cylinder.

Check: For basic engine mechanical or cylinder fuel delivery fauilures. (Low compression, faulty nozzle, fuel leak, restricted high pressure line, etc...)

[westcoasttowing]

I did a compression test. got a consistent 200 lbs in all cylinders but the motor was cold. today I started it up again. runs kind of okay cold but as soon as it warms up or if i drive it a couple of hundred feet it just runs terrible starts missing real bad, then I was revving it and it quit. Then real hard to turn over. no start. When it cooled down then it started. ??????

[westcoasttowing]

using a stethascope on the drivers side valve cover, I detected a loud knock towards the front. Actually I hear it loudest right in between the embossed GM logo. right between the G and the M. As I scan around on both Valve covers I hear equal tapping sounds of pushrod/rocker arm assy. But right there at GM I can clearly hear a knock. I cracked the fuel lines on the first two injectors and the knock was still present. That should cancel out injector issues. Could it be a stuck lifter. I am also noticing when I shut my engine off residual blow-by coming out of my air filter box. I am also now hearing a hi pitch squeal that comes and goes when the motor warms up and starts to run like ****.