A guy from a local board reached out and asked me for some help because I have an AE scan tool with the Ford module.

Email:

hey i have a 99 power stroke thats been nothing but problems. Master tech mis diagnosed me more than once to the sum of about $2000 in parts and my truck is still running the same. I saw a thread that said you had a good scanner? I have a cheap one it said no dtc's. Im not sure if I'm just not using it right or what. anyways I've been to hell and back and don't know where to start. I was planning on just taking it to ford but i don't want to go give lithia $200 to mis diagnose it again. Ive got 2 whole pay checks into it already and have gotten no where. It has new hpop, lpop, icp, ipr, idm, fpr, cps, and I'm sure there is more that I'm missing. before i pulled my valve covers it would drive but like crap. now that i put them back together i get a horrible surge at idle and it won't rev. id will sometimes but hits a certain rpm and cuts to 0. I'm lost and could use as much help as I can get... I was going to see if there is a possibility you may be able to come throw it on your computer and see what it pulls. or maybe help take a look at the symptoms and see if it is something maybe you have felt with? Ive owned it 3 months and its been broke down for 2 of the 3. This is my first diesel and I am totally lost. Sorry to bother you I'm just running face first into a brick wall over and over again. Thanks Ryan

I asked him if his was an early '99 and he told me it's a hybrid with AB injectors. He says the truck will start, but it runs like crap.

I would think the only thing that's left is injectors.

Any thoughts on this issue? What should I look for when I hook it up to the AE?

 

Did you check the valve covers? the wiring foe the glow plugs and injectors are built into them, not a great idea but it worked, there known for failing and you lose power to the injectors. You need a scan tool to get in there and see whats going on, throwing parts at it is not the answer. Scan it, pull codes and see what you got.

 

Pull the codes, do a KOEO test, do a buzz test, then fire it up and do a Cylinder Contribution Test while recording the Cylinder Rotational Velocity on all 8 cylinders.

If nothing is found by this point, go for a drive (don't forget to "stress" the engine by applying the throttle hard) while recording the usual suspects (omit the Transmission Temp for this test):



It sure sounds like a UVCH, or a stock tune with hybrids.

 

If a stock tune with hybrids, what are the guy's options? New stock injectors?

I've been unsuccessful recording anything on AE. It hasn't worked thus far.

 

If they're ABs, they aren't hybrids. There isn't very much difference between an AB and an AD. Ask him what the manufacture date of the truck is, and how many bolts hold the turbocharger compressor housing to the backing plate. I think he probably means he has an early '99 that's been "hybridized" with some '99.5-up parts. Probably a good idea to ask about any mods like chip/tuner, etc. too.

 

I have a buddy with an e99, and for the life of me I could never get my AE to talk to his truck properly. I could either pull and clear codes, or run tests. Could never do both at once. So if I pulled and cleared any codes for him, I would have to close out of AE and start it back up again and click "none" when it asked me what codes I wanted to pull. THEN I could get it to run tests. Had to be something with the e99 model, because my AE works fine on other trucks, including my OBS.

Anyway, it's just a thought. And I would definitely check the UVCH's.

 

Not a lot of symptoms to go on, but sounds like the accelerator pedal switch is not responding properly. Pretty sure AE can read that output voltage, should be a steady change. Contact cleaner spray might help get the switch working.

 

He's currently installing new Motorcraft valve cover gaskets with internal & external harnesses and a set of Motorcraft glow plugs. I'm going to meet up with the guy between 1:00 & 1:30pm today for any help I can offer. Hopefully he's got all of this stuff installed and everything buttoned up before I get there and we can scan it. Might as well

Would bad external injector o-rings cause this much trouble? I'm not sure the mechanic messed with the injectors, but if he did, shouldn't the oil passage be drained to avoid leak down? Would that cause something similar to these symptoms?

Where is the accelerator switch located, at the pedal or under the hood? I should know this, but I've never dealt with an issue like this on this engine. I could replace one blindfolded on my 6.9L IDI.

 

Switch is part of the pedal assembly.

 

Connected. Looks like his GP heater doesn't check out. ICM was mentioned too.

 

P0472 exhaust pressure sensor low
P0380 GP htr circuit A
P1274 cyl 4 high to low side open

 

Is the EBP sensor harness disconnected? If it's not disconnected, the brown wire with white tracer should have +5 volts on it, and the grey wire with red tracer should have continuity to ground.

The GP circuit code shouldn't affect the way the truck runs once it warms up a little.

The high to low side open code could definitely cause rough running. Check the resistance from the VC connector or 42 pin connector to that injector solenoid. Probably a good idea to check all the resistances on both banks, as long as the meter is out

 

It won't even start.

 

Well that changes things a little bit. Set up AE to watch RPM, ICP, IPR duty cycle, Injector Pulse Width and battery voltage while cranking. You should see at least 100 RPM, 500 PSI ICP, and > 10.5 volts. If all that is in line, injector pulse width should come up from a standby level to above 1.0 ms. If all that happens, the truck should start.