first a little info on the truck, its a 94 12v with a 5 speed, no plate, maxed star wheel, waste gate has been messed with, everything else pretty much stock. so the truck always runs like crap until its warmed up, it just runs rough, pretty much expected with fixed timing. but this morning it wasn't even cold out(i live in Florida) and it started right up but when i gave it a little bit of throttle is ran rougher then ever and was just boiling out white smoke. once it warmed up it was back to normal but iv never had it run so rough before. the only thing that's changed on the truck is yesterday i pulled the intake elbow to paint it, changed the oil, and built a 5" exhaust system, im thinking maybe the intake heater got messed with when taking off the intake elbow?

 

Sounds like your timing has slipped. Need to have it checked and set at about 15. Then it will fix the rough running when cold. My old 97 had the same problem until I set the timing.

 

o, that makes sense, so by slipped do you mean increased or decreased? wouldnt it run better cold if it decreased?

 

Check your overflow valve. I had that exact issue and the valve was worn out. Check Ebay and get a genuine Bosch part. Something like $45 and 10 minutes to fix it. The smoke should be consistent if you have timing probs from what I understand.

 

By slipped I mean its injecting fuel to late so it doesn't have time to burn it. Even a stock 12v benefits from the timing set at about 15-16 degrees before top dead center compression.

 

ok, well i planned on doing the timing anyway. im just saving my pennies for a good dial indicator to do the job, i get a great discount with matco for being a student so ill be buying some more tools here pretty soon and ill do it then. from what iv read it doesn't seem like a big deal to do.

what overflow are you talking about? being that your talking about bosch parts i assume its related to the injectors? im not real familiar with this truck or any of its common problems, iv been int he diesel game for about a month now...

 

Its a banjo bolt on the IP fuel return line. It has a small check ball/plate and spring inside. When they wear out some of the common symptoms are hard starting, rough idle, white smoke, and low power. OE recommendation is to replace them every 100k miles. Before I replaced mine it would idle smooth then sputter and give white smoke until it got a little warm. They retail for around $100 which is why I said check Ebay.