Ok, little background. My stock F350 has a miss between 132-168 ECT. It starts great, idles good. I let her warm up a bit lets say to 100 degrees, and then start driving. Drives fine until it hits 132 degrees. Then it starts to studder or miss starting at 132 and then stops doing it at 168 ECT. I've checked the FICM and I've got 48 volts. Go no codes. If this was injector stiction, then I would assume that below 132 degrees the problem would be more pronounced instead of not there. Any clues anyone?

 

maybe the egr valve is opening

 

EGR valve was replaced about a couple of months ago. Did have a look at it too though. Other than the usual soot, not much to report there. FICM repaired about a year ago. Only thing I can think of is maybe MAF sensor or something. Do any sensors come in in stages? Say three or four levels of output from one and the middle ranges being screwed up?

 

Need to watch a "live" datastream to pinpoint this problem.

 

gonna be an injector that seems to like to get stupid at a certin temp.

 

I hoped you wouldn't say that. Any simple way to test for that other than with an IDS?

 

subscribed...my no-go incidents all started at about 135 ECT. Not sure if this is coincidental or related it worth following...

 

only reason why i said the egr valve was because my dads dmax would have the egr valve kick in after the truck was hot and it ran terrible and made weird sounds. i know they are 2 different motors but havent heard much on anything in your case. cheezit will know the best here!

 

Mine does something similar, but it clears up at exactly 150 F oil temp. No egr to worry about. Ficm is good too. ICP readings look good too. 2500 rpm has the worst "shake," if I keep it under 2000 rpm I don't notice it. I just assume it it's tired injectors @220k+ miles on the truck.

 

IMO oil starts to change visocity as it comes up to temp. this may also be a result of that.
but so far as I knowIDS is the way to go.

 

Oil viscosity will change in a range, depending on it's age and composition.

This sounds very much like a fueling table transition as the engine warms up, combined with tolerances very close to an "out of tolerance" condition in an individual injector.

As the injector temp goes through the temp range, the tolerances will go out-of-spec and then back into-spec. While they're out of spec, the injector will throw fits.

It will be remarkably difficult to find without IDS or AutoEnginuity.

-blaine

 

This condition may also be a subtle and off-the-wall notification that your fuel may not be treated with the proper lubricity additive.

My Detroit will do this at idle when the fuel I buy isn't properly treated.

As an interim fix, try adding a lubricity additive (Power Service is easiest to find; double treat, though). See if it changes the behavior any.

-blaine

 

ford's cetane booster will help at every fillup. 1 6oz bottle per fillup. dang. 132 degrees is too early for probs. then again, the guys are right about tat oil range thingey.

to the OP, wat kind of oil are u using? when was the last oil change? also, wat kind of oil filter are u using too? all these make a huge difference. since it's cold in canada, besides the cetane booster, try using a heavy duty 5w40 full synthetic. it might help better in cold starts and also, overall performance is better for ur kind of climate.

 

Well just to keep everyone updated, Cheezit was correct again. #3 injector has since been replaced. No more problem.

 

sorry ill do better next time