rough running 124 e300 after 3 min

[d sangastiano]

hello everyone,i am new to this site & need help.i have last year 124 (95)with first year 606 engine.217000 miles.when vehicle is started runs great,after 3 minutes runs rough,misses & white smoke.this last about 5 minutes then runs great.road testing performance is excellent.if driven hard injectors knock.vehicle had vacuum pump & timing chain replaced last august & injectors replaced.compression 25 25 23 25 25 25 bar.cyl leak 8 8 8 5 4 5 %.tested preglow system,after glow system,nothing vacuum related,or electrically related.injection pump was rebuilt & same problem.in the event the rebuilt inj pump was not correct in installed a known good inj pump from another 95 124 with 606 with 90000 miles & had same result.swaped injectors & same result.fuel has been replaced as well a fuel tank strainer which was clogged(a few months prior)coolant is never low.coolant tank pressure tested overnight & engine was borescoped-looked ok.advised friend had same problem & his problem was head gasket.so i removed head & inspected.could see nothing concrete.r&i all valves & cleaned & inspected,spings,valves ok.head not warped.reassembled & same problem.crosshatch on cyl walls & perfect & internals of engine is spotless-vehicle is very well maintained.replaced platic fuel lines & installed modifyed line with banjo bolt-no air bubbles in fuel lines.running out of options.engine harness is in poor condtionvehicle awaits me on monday.have been working on since fri 4/6also engine timing is dead on & inj pump timing spec is -14.5 have set at -13.8

[TMAllison]

Sounds like you've checked the obvious things like GP's and the timer relay.

A bad wiring harness can cause lots of difficult problems to sleuth out.

Your problem seems to occur between the time the GP's shut off and you reach 80C operating temp; may be a problem with the fuel thermostat or the computer itself.

Have you tried to read any stored codes from the computer? Is accessed from the connector in the engine compartment.

*edit*
"Arthur Dalton's" radio shack code reader..... E320 16 PIN DTC Charts inc. pin 8, pin 14