Engine bucks, a loss of power check engine light comes on

[imfarny]

This weekend our motorhome with 6.5TD stalled. I restarted but there was no power to speak of. Shut it down and waited a while restarted and it ran fine for a while. Cruising at 55 the engine would buck and there was the loss of power and the check engine light would come on. It could be driven but would not shift into OD and cruise would not work. Stop shut it off and down the road we go everthing working fine for a while. Repeated this sequence several times on the 300 miles home. Any ideas out there? don1@adiis.net

[MTTwister]

Naturally, first thought is PMD \ FSD - do a search on those terms and see what comes up.

When my PMD was failing, it would randomly drop out of cruise, occassionally a slight buck. Others have had worse.

However, check all grounds - batteries to block, block to firewall to frame. These also can give you fits.

Others more knowledgeable will chime in soon.

[rameye]

What code did it throw??

[imfarny]

I got a chance to check the codes tonight. The sequence was 18-35-54-13. I read what they are but sill don't know what to fix. This is my first diesel and it has 16,000 miles on it. Records show that it was well maintained. It's in a 26' Trek motorhome weightin about 14,000 lbs. loaded.

[rameye]

I had that sequence when my IP bit the dust...not saying that's it however.

You need to verify good fuel pressure when running.
Clean check ALL grounds/ battery connections.
Inspect harness at wear points in engine compartment.

If all checks out...try to find/borrow a known good PMD and swap it out for testing purposes.

If that still doesn't work, start looking at the IP the code sequence is certainly in order.

Take it slow, relax, read, ask questions, get informed, these are great little units once you understand what goes bad. Dont freak, we've all been there.

ram

[Kennedy]

That's classic symotoms of a failing encoder sensor, and the DTC's confirm this. My best suggestion is to replace the pump and start fresh.

[imfarny]

Thanks guys. It was the IP and it was replaced under warranty. They insisted on putting on a new PMD also because of the code 54 (at my expense). I will pick it up Saturday.

[Andy Chesek]

Um, isn't the PMD considered part of the pump when replaced under warranty?

[DmaxMaverick]

Originally posted by imfarny:
Thanks guys. It was the IP and it was replaced under warranty. They insisted on putting on a new PMD also because of the code 54 (at my expense). I will pick it up Saturday. The PMD is an integral part of the pump, according to Stanadyne, when it is replaced under the campaign warranty. Stanadyne provides the pumps w/ a PMD attached (either actual, or by exchange of funds). Your dealer may, or may not, know this. If they read the bulletin, they should know, as it is spelled out in detail. Your dealer is getting extra money from you. Definately question them about it, and of course, don't pay them for something they didn't pay for. If you can, get the old PMD and keep as a spare (odds are you will need it before the pump fails again). They are supposed to destroy the removed pump and PMD when the repair is complete. The disposal instruction specifically mention a large hammer, and remaining pieces small enough they can't be salvaged.

[imfarny]

Thanks again for the help. I misspoke, it was the PCM that was replaced and a wireing harness that had heavy resistance. The motorhome is running fine now.