2008 E-450 Falls Flat On Its Face

[mchan68]

Got one here. An '08 E-450 that can't get out of its own way. Only DTC is P0341 On-Demand. Monitor PIDs during road test and FICM_SYNC and SYNC always indicate YES, so I can't see any CMP or CKP signal dropout. Passes IDS EGR test. All other PIDs look good. Feels like the engine runs rough. When I attempt to look at power balance or run a relative compression test, I get kicked out of the test with the pop-up window telling me there is a synchronization error between CMP and CKP, yet FICM_SYNC and SYNC indicate YES under all engine running conditions. The engine does run a little rough too. Just wondering if an engine harness could possibly cause this issue? I doubt it, but I don't know where else to look. Again, all other PIDs look normal (ie ICP volts, ICP psi, IPR duty cycle, EBP_A, MAP, BARO, FICM_L, FICM_M and FICM_V etc.).

[Shlep]

Depending on how rough it's running it might set flag for loss of sync while doing a power balance test but it would have to be pretty extreme. Had a few harnesses with shielding damage cause it but they would loose Sync while testing. A noisey alternator could also be the culprit. Whats the MGP and Mass fuel desired doing when it looses power? VGT% and EBP?

[Bruce Amacker]

+1 on checking the alternator, try unplugging it. I'd be getting my scope out, reference known good waveforms are in my pics. Also look and see if anyone was messing with the harness- if the polarity is reversed in the sensor harness during pigtail replacement it will give a similar complaint.

 

The E-van is a bitch to put a harness in. Would it be easier to overlay the harnesses for CMP/CKP for diag? If you're not a scope dude, maybe try hanging 2 sensors in it first? You're in the rust belt, could rust under the sensor flange cause this?

 

Good Luck!

 

[mchan68]

The unit is a Go-Transit utility cube van with 140,000 kms. on it. The last repair I did to to it was a cylinder #8 injector and a catalyst back in June of this year at 117,000 kms. I already checked the basics (air filter restriction, fuel quality check, and the "tap test" of the cat etc.). Driving it feels almost like a stuck turbo not building enough boost. I would've thought that the IDS EGR test would've caught something but it didn't (all values dead smack in the middle of the green zones). It does NOT flag a P2614 and P2617, only P0341 by itself. Not sure on the alternator. It MIGHT have an aftermarket alternator in it, if it matters.

[Bruce Amacker]

It MIGHT have an aftermarket alternator in it, if it matters.

That wouldn't be my main concern but rather a bad diode or brush bounce which causes really freaky voltage spikes and wicked electrical noise. BB is usually seen on vehicles that have been parked an extended time allowing corrosion to develop on 90% of the commutator, not really a popular problem but worth mentioning. Too bad IDS won't allow you to command the alt off, that would be a helpful addition.

 

Good Luck!

 

[GregKneupper]

you have to clear the p0341 from memory before it will let you perform a power balance test. just the code in memeory will not allow you to perform that test.