Ok so i am going to be a noob here.. asking on behalf of my brother who got a 94 2wd 5sp a few months ago. Truck has 180xxx miles.. AFE Intake.. JRE fuel plate, banks exhaust, EGT/Boost apillar guages. Towed our 16' trailer great last weekend. Now its having a problem. The weather is plenty warm here (50-70).. the truck cranks and sputters big time when starting. Once it warms up it runs great in the upper rpm range.. but if you let it idle it will idle nice for 5-10 seconds and then miss and stumble and usually stall.

Blows white smoke for awhile until its warm (always has when started cold).. blows a medium amount of black under load mostly because of the fuel plate i suppose.

Changed water separator canister and oil (which looked good)...

I've heard everything from fuel line deterioration, to injectors, to injector pump, to glow plugs.. we know nothing about diesels and hope to narrow it down.. and hopefully fix it right (and cheap hopefully)..

Any thoughts as to what it could be?

 

First things first just FYI cummins dont have glow plugs they have intake heater grids. It sounds to me like you have either some timing that slipped retarded or you have a return check valve that has failed, other things to check are lift pump pressure and volume, check for any air leaks (unlikely), or one or more stuck injectors or delivery valve or holder issues. if you need any suggestions or test procedures for any of that just let me know.

chris

 

can't be glow plugs, these trucks don't have them.

we have grid heaters, sorta like a toaster in your intake.

never use starting fluid on it!

Those temps don't look like it would be a grid issue.

White smoke is a tell tale sign of air in the system. sounds like it drains back overnight.

If it clears out and runs fine after a while I doubt it's youre timing.

If you have the original fuel lines, you will want to replace them.

you could have air leaking in around the fuel heater.

you could also have a bad overflow valve.

best bet is to pressurize your'e fuel tank with 3-5 psi and listen/look for leaks.

 

It doesnt get "better" overnight.. its a constant problem. Its just very difficult to start all the time (sounds like an old POS carbed motor leaving you stranded somewhere)..

It can be driven all day.. then you let it idle and it will stumble and stall like i said.

Any writeups/descriptions would be helpful.. as i have no idea what we're doing with this beast.