lopey idle?

[Hooper]

Dave, do you use 5w40 all year and change back to 15w40 during the heat of
summer? I've always used Valvoline Premium Blue 15w40 and change it about every 3500 miles. How do you think the 5w40 will fair in Hemet when it's hot? And what about the oil would cause the miss??

 

[Zookie400]

the 7.3 and 6.0 PSD's are HEUI engines.
Hydraulic
Electric
Unit
Injector

the injectors use high pressure engine oil to push the fuel through the nozzles. bad oil, wrong oil, aerated oil.....will cause issues with the injection. it could also be the other parts of the high pressure oil system like the pump, regulator, sensor....

some people have been finding good results from installing a high pressure crossover line (HPX) it connects the two banks and equalizes the pressure on both sides.

hooper: if it only does it when its cold, you may have a few (or one...) bad glowplugs. the cold cylinders need the heat from the glowplug to fire, until the engine warms up and has enough heat to sustain proper combustion without aid. a cold cylinder or two would cause a funny idle.

 

[bigrigr]

Thanks to all, I'll check those injectors next. Probably won't worry about the speedo right now. Got bigger fish to fry.

 

[aggitator]

do you unplug the injectors while the motor is running? or restart after un pluging the injector?

 

[Zookie400]

do it with the engine running, taking special car to keep fingers out of the valvetrain, although i dont fear touching any of those moving parts, nothing to "bite" you really.

after you plug one back in, give the engine a few seconds to "stabilize" before going for the next one.

 

[bigrigr]

Aggitator, unplug the injectors one at a time with the engine running. Listen for the one that doesn't make the engine run worse, or that doesn't make as much difference.