Engine/Transmission (1994 - 1998) Missing / Running Rough 1000 rpm

[Treb]

A friend of mine just bought a 95 model with 185,000 miles. Now in the mornings when he first starts it (while it's cold), it is missing and running rough, especially when you rev it up to about 1000 rpm. White smoke, too.



He said once it warms up and when he has it on the highway it runs fine, but until it warms up, it's running really rough.



Any ideas?

 

[Todd G]

Bigger injectors or lack of timing can cause this when cold. Mine does the same thing.

 

[Treb]

He said he just recently changed the injectors because he thought that was the problem. Said the injectors he took out were marked "260 bar" and the ones he put in were "220 bar". I would think that this would advance his timing a little since the injectors would pop off earlier. I didn't mention this first because it had the same symptoms before he changed the injectors. Could be he changed one problem for another, I guess. . .

 

[dalton4]

Is the intake air heating grid working? If not, this will be a negative for cold starts.

 

[crabman]

Treb,

Has he changed the PITA fuel lines(supply & return) since he has had the truck? If not, it is a good thing to do so you know it is NOT the problem(s). Also a good time to replace the starter contacts.

The white smoke & running rough was what mine done on cold start ups before I changed the fuel lines.

crabman

 

[redram]

If this is only happening following a longer shutdown, this is a classic indication of air getting into the fuel lines, hence injectors and until this air is purged through the injector lines, it will run rough and have white smoke. I noticed a distinct increase in deisel fuel smell even though you did not see evidence of a fuel leak. When looking closely at the fuel lines, the outer rubber was hairlined cracked due to ageing which must have allowed air to leak into the fuel lines, causing a loss of fuel prime making it hard to start resulting in rough idle and white smoke.