Tons of white smoke after cold start,,,

[94GMC2500]

Hello,

I just got this truck a few weeks ago, its a 94 GMC 2500, 6.5 turbo, 5 speed, 4x4.

The original 6.5 was bad so I pulled the 6.2 out of my old rusty Suburban, put late model 6.5 heads on it and all the other 6.5 stuff originally on the 94 truck. The 94 6.5 heads were cracked really bad.

I installed rebuilt injectors, made a rig to test 4 glow plugs at a time on a battery so I know they all work and heat up in the same amount of time. I know the short block is in good shape.

It has a Heath chip and a manual boost control.

It starts great in cold weather. The video link below was after a cold start at just above 0 degrees F, problem is after the start it makes TONS of white smoke and pops and farts for about 6 minutes before it finally runs on all 8 cylinders. It was the same deal this morning at about 35 degrees F.

I have tried the stock chip in the computer, another pump driver, advancing the pump a little but nothing helps. If the wind blows the smoke at the house the whole house smells like diesel inside. It makes me feel sick if I am anywhere near the smoke it as it warms up.

Did I lose too much compression with the late model {2000 I think} 6.5 heads? I could get my compression gauge in only 7 cylinders, could not get in the back pass side without removing the down pipe. I had 360 to 380 psi compression on a slightly warmed up engine.

I am starting to wonder if there is a problem with a couple of the rebuilt injectors I got.

After it warms up it runs great, in fact it hauls a$$ for a old 6.2, 85 mph in 4th gear in no time at 12 lbs of boost.

What do you guys on here think? Should I pull the injectors and have them tested? I am about out of ideas otherwise.

Just to make it clear it starts awesome at 0 degrees without block heater, the problem is smoking out our yard or the neighbor's yard after it starts.

[rmilsap30]

Mine does the same thing. It is a stock 93 6.5TD and it really does lay down some smoke in the morn. just like your video. Runs great after been running for about 10 min. and is warmed up then no smoke. I will be patiently waiting an answer for your question. Sorry I was no help but am curious as to the remedy.

[DennisG01]

If it starts a 0* with no block heater, I'd say you're doing just fine.

How is it when it's been plugged in for about 3 or 4 hours? Better?

How about doing a couple of glow cycles, first?

Extending the glow cycle via the push button method may be a good idea for you. Especially if you aren't going to be using the heater. Although, the heater is there for a reason - use it Unless, of course, you don't have access to a wall plug.

[phantom309]

when it starts and runs rough with the white smoke,. do you have any throttle response? will it rev up some and catch on all 8 cylinders, clean itself up and then run with no smoke??
i have the same problem with my 94,. i have a constant code 36 with the truck warmed up and driving ,.when its cold it will light off with the 8 new injectors and 8 new bosch duraterm glow plugs,. but it rocks and rolls and has clouds of grey/white smoke,. sounds like its running retarded and waay too rich , same as yours the smell of unburnt fuel is overhwelming,.
when its cold i have zero throttle response,. till it decides its warm enough to run right,. that may take up to 5 mins,. if its f-f-freezing cold (-5f) and not plugged in,. plugging in reduces the amount of time till its happy by quite a bit,.
I talked to my pump guy and he talked about a poppett valve(sp?) in the back of the pump that gets worn and doesn't seat properly reducing the amount of internal pump pressure (or thats what i think i thought i heard him describe,. as my eyes slowly glazed over,.) and will cause this problem when its cold,.
I,ve learned to work around it,. always face the pipe away from the house,. always plug it in when its bisch cold,. and give it 2-3 mins before i try to drive it,.truck gets great fuel mileage,. and runs really nice after its done this bs first start of the day,. even up to 8 hrs later all is fine,.
When the weather gets warmer i'll peel the pump off and he says $300 will fix it and he'll re-calibrate it at the same time,..he may be full of bullsht too,. who really knows,.

Nick

[tall78]

Sounds like I'm not alone. Best advice I have come up with is change the timing chain to a gear drive. these motor s react to very fine adjustments. I think the chain has too much variation.Thus , rresauling in too much change in timing. DSG PHASER KIT ismy next step.

[JohnC]

DTC 36 is a problem with the fuel solenoid. This is what controls the fuel rate to the engine. When the PCM can't control it the PCM will disable the throttle to prevent sudden unintended acceleration. Sounds like the pump guy is on the right track...

[94GMC2500]

when it starts and runs rough with the white smoke,. do you have any throttle response? will it rev up some and catch on all 8 cylinders, clean itself up and then run with no smoke??
i have the same problem with my 94,. i have a constant code 36 with the truck warmed up and driving ,.when its cold it will light off with the 8 new injectors and 8 new bosch duraterm glow plugs,. but it rocks and rolls and has clouds of grey/white smoke,. sounds like its running retarded and waay too rich , same as yours the smell of unburnt fuel is overhwelming,.
when its cold i have zero throttle response,. till it decides its warm enough to run right,. that may take up to 5 mins,. if its f-f-freezing cold (-5f) and not plugged in,. plugging in reduces the amount of time till its happy by quite a bit,.
I talked to my pump guy and he talked about a poppett valve(sp?) in the back of the pump that gets worn and doesn't seat properly reducing the amount of internal pump pressure (or thats what i think i thought i heard him describe,. as my eyes slowly glazed over,.) and will cause this problem when its cold,.
I,ve learned to work around it,. always face the pipe away from the house,. always plug it in when its bisch cold,. and give it 2-3 mins before i try to drive it,.truck gets great fuel mileage,. and runs really nice after its done this bs first start of the day,. even up to 8 hrs later all is fine,.
When the weather gets warmer i'll peel the pump off and he says $300 will fix it and he'll re-calibrate it at the same time,..he may be full of bullsht too,. who really knows,.

Nick

Throttle works, I don't get any codes/check engine light. If I leave it run a couple minutes and then drive it the smoke cuts down much faster. People don't follow to close for a while till it warms up though LOL.

Tom

[Old6.2]

I had a similar condition on my NA 6.2 after I had my injectors rebuilt. Seems the old pump could not handle the higher pressure of the renewed injectors. A pump rebuild cured my white smoke at startup.

[bobbywalter]

looks like a cold idi start to me...bit heavy but similar to any i have seen.

if overall economy is good i would run it.

[DaveBr]

Put a couple of qts of unused engine oil in your fuel tank next fill and see if the smoke clears faster. Higher viscosity fuel makes it harder to bypass IP plungers. If it quits or cuts back smoking significantly then you know your pump is worn out.