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Surge at 2000 rpm

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2005 f-250.Has a surge about 2000 rpm.Have tried and looked at everything.Called hotline no help.Only thing to go on was turbo just replaced at other dealer.passes every test on ids.passes turbo test and installed new egr valve.Help please

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The first couple of things that come to mind are to graph out some PIDS and see what is cycling the hardest when the surge is present. I'd be looking at ICP, EBP and VGT% first. A bad ICP sensor connector will cause surging, as well as a sticking turbo, carbon clogged EBP tube, wacky EBP sensor, among other things. Just 'cause the turbo is new doesn't mean it's good. When was the oil change last done?

 

What are the ICPV, MAP, Baro, and EBP readings KOEO? I'm BIG on looking at these before I even start the engine. Map, Baro, and EBP should be RIGHT on top of each other. Baro is usually the most accurate and EBP is the least accurate. You should know these readings for your altitude, it's 14.7psi at sea level, your elevation is about 850ft so it should be about 14.2psi. IDS checks these during the EGR test, but I'm fussier than IDS is.

 

Have you checked fuel pressure? I've seen FP do odd things also. Does a fuel sample from the lower filter look good? You'll need a funnel and a glass jar or water bottle for a good sample.

 

Grab the Performance Diag Sheet and go over the steps one by one. Every base has been covered?

 

If all of this checked out I'd unplug the ICP, EGR and turbo actuator and see if it still did it, and what PIDS cycled. It could be a long shot, but oil aeration from a weak LPOP might cause this also.

 

All of this checks out? Unplug the alt(s) and see if the problem is still there. Excessive ACV will piss off the PCM royally.

 

Two grand you say? In neutral? Under load? From 2000 to redline? Please be more precise about the exact time the complaint happens and what has already been done. "Have tried and looked at everything" isn't specific enough for me.

 

Good Luck!

 

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Hi Bruce,

Did verify the map,baro and ebp all close.Removed the ebp and tube,but no blockage.Fuel pressure is at 45 at wot.fuel quality is good.Oil looks good and is full.Made some recordings and sent them to hotline.The weirdest looking thing is the egr looks wack proportional to ebp.icp looks steady.Inspected that connector also.Customer did state no problems before turbo failure.Other dealer stated shaft and impeller,turbo vanes destroyed.Did not find anything in downpipe.Thanks for the input.

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Something sounds very familiar about this one... I looked deeper into old posts but didn't find anything on this...Jim/Keith any thoughts on this. I found the other post with a major turbo failure/repeat.

 

http://www.forddoctorsdts.com/forums/ubb...=true#Post12949

 

May be worth a look....

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I've had some early builds with what I would call a "random misfire" - well, almost - in the 1800~2000 range that turned out to be HPOP check valves.... Bring your rpm up to start your symptoms and then vary the IPR to see if anything changes....

 

Worth a try.

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"Verify operation of the bank 2 check valve. To isolate bank 2 check valve disconnect all bank 1 injectors.

Start the Power Balance test and monitor the cylinder power contribution while the symptom is occurring. Engine misfires should be constant on the 4 cylinders with the disconnected injectors. The 4 cylinders with the injectors connected should be contributing evenly.

Connect the bank 1 injectors and verify operation of the bank 1 check valve by disconnecting all bank 2 injectors.

If the 4 cylinders with the injectors connected do not contribute evenly or display erratic, install a new check valve for that bank."

 

All that stuff above is from Step 6b on the performance diag sheet. I think that is what Jim is talking about checking but in a different way. I'd also try reprogramming the PCM and maybe checking out the transmission. Good Luck.

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Well,took turbo off to inspect.found excessive play in turbo.Saw the post on repeat failure and was wondering exactly how you perform a cranking flow test?I'm afraid of another turbo failure.

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hey kelly whats the ipr and icp doing when the surge is happening? Had an issue one time that the hp stc connector wasn't blown off, but was a "loose" fit. I disassembled the engine and when found this cranked the engine and actually watched this bastard leak with a heat gun on it.

 

PS, DIDNT MENTION YOU'LL WANT TO TAKE A NEW TURBOCHARGER OIL FEED LINE AND PLUG IT SO YOU DONT HAVE A REAL FRIGGEN MESS.

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