Intermittent stalling

[Archive]

OK guys! Here is a problem that is driving me and the mechanics nuts. It's one of those intermittent things that are very hard to diagnose. First I'll describe what triggers it and then what the symptoms are. The problem occurs more frequently on warmer days. It only appears when restarting a warm engine that has been shut off for 5 to 30 minutes. It usually lasts until you physically turn the ignition switch all the way to off, wait a minute or more and restart. Sometimes you may have to do this a couple times. Sometimes the problem repeats after this but it never goes away unless you shut the switch off and restart.
OK, the problem, sometimes but not always when restarting a warm engine, it will start harder than normal. Anywhere from a couple extra revolutions to continued cranking. When started it usually runs fairly well for the first mile and then starts coughing and stalling like it were running out of fuel. If you release the throttle it will immediately accelerate briskly for 5 - 6 seconds and then stall. (This is not good in heavy traffic!) If you push in the clutch it will red line up to around 4000 rpm and immediately stall. If you continue to let it coast during the coughing and stalling it will continually cycle through that and restarting, like it was getting spurts of fuel. If you let it coast to a stop wait and restart without returning the key to the off position it will continue to cycle as above. I have found that if you turn the key all the way to off, wait a minute or more and restart it will run normally afterward about 70 % of the time.
I have had it to a couple different shops and one has researched a number of others and can not come up with an answer. The problem is it has only done it once while in the hands of a mechanic. So far we have cleaned the injectors, replaced the return line, replaced the return check valve, checked the pump pressure (about 30), checked the shutoff solenoid function, inspected everything multiple times for leaks and found none, replaced the fuel filter twice.
The truck is a 95 and never gave me any trouble until about 6 months ago when this started. I am no expert on diesels and am looking for any suggestions as to what the problem could be and any recommendations. Its driving me nuts!
Tim


------------------
Tim Wafer