Hi there,
Please bear with me, because I know very little about truck engines. My boyfriend drives a 96 F-250 manual powerstroke diesel that idles too high when it warms up (shakes the whole thing- you're like to loose a filling). Where is the adjustment screw for the idle?
Thanks!
Nicole
coilproinc(No Email Addresses In Posts!)

 

There is no idle screw. The computer does it all. He'll have to get the codes out of the computer to find out why it is idling too high. Does it seem to run right when it warms to operating temp?

 

No, actually, the opposite is true. It seems to run okay when it's cold, only once the engine warms up does it start shaking, and even then, it doesn't do it all the time. But at least now we can stop looking for an adjustment screw!

 

Like Joe said, you will have to have the codes in the computer read to see what is going on. Ford or a shop with a code reader for the diesel should be able to help you.

Les

 

It sounds to me like it has a cylinder not firing intermittantly. Ford has a diagnostic tool they can plug into the diagnostic port and do a cylinder contribution test.

 

>It sounds to me like it has a cylinder not firing
>intermittantly. Ford has a diagnostic tool they can plug
>into the diagnostic port and do a cylinder contribution
>test.



A cylinder contribution test can be missleading. I have diagnosed 2 (of many) powerstrokes that passed the cyl. cont. test even though there was a very noticeable miss. Using a performance annayizer is the best. you can kill one or up to 5 cyl.s with out killing the engine. Using this you can definately tell if a cyl. is week or not.

 

You are correct about the cylinder contribution test as it applies to a weak cylinder but Nicole has indicated that the engine (or truck) "shakes" after it gets to a fully warmed condition which sounds more like a dead cylinder instead of a weak cylinder. If the contribution test was done while the engine were shaking, it shouldn't be too difficult to locate the cylinder in question (assuming that is even the problem). The contribution test is difficult to get any meaningful results from without loading the engine, which is also hard to do without a floor dyno. It is also possible that there is a code in the computer that has already diagnosed the problem.

 

Nicole,
When the engine is running ruff does it sound like it is missing and there is no power - not even enough to let out the clutch (killing the engine almost immediately)?

If so then the problem may be with the valve cover gaskets - the injector wiring harness runs through these. My nephews truck had the problem at 80K miles and mine at 120K.

In any event if your boyfriend doesn't have the background/knowledge to diagnose and repair on his own he should take it in to either a dealer or truck shop for an estimate of repair.

>Hi there,
>Please bear with me, because I know very little about truck
>engines. My boyfriend drives a 96 F-250 manual powerstroke
>diesel that idles too high when it warms up (shakes the
>whole thing- you're like to loose a filling). Where is the
>adjustment screw for the idle?
>Thanks!
>Nicole
>coilproinc(No Email Addresses In Posts!)

 

 

My powerstroke idled like that and after checking it..I found the wiring plus to my injectors were lose. Made it a tight fit and it was good as new

 

Damn, this post is 10 years old.