EDR

Happy New Year!

I usually post in the 3rd gen forums, but I’m posting this for my Dad.

He’s looking for any ideas or suggestions on what the following issue may be and for a good diesel shop recommendation in the Southwest Denver or Colorado Springs area.

The truck is a 1995 Dodge 2500, Cummins 12 valve (175 HP), 4 wheel drive, standard with 142,300 miles.

In 2005 he took it in to Central Motive Power in Denver and had the injectors replaced with rebuilt ones (P/N SR 042 133 858?). The shop installed “larger” injectors to give it more power for climbing the mountains, but he mentioned that he went down from 20+ MPG to around 16 MPG, mostly highway and mountain driving. He also said he didn’t feel a noticeable change in power or performance.

The injector pump was replaced at the same time, and he doesn’t know what the timing setting is or if it has changed. The fuel pump is original and hasn’t been checked.

He’s retired and doesn’t drive the truck a lot these days, but he has noticed a miss at about 2000 rpm when climbing a hill while pulling a trailer (1000 lbs +) or under hard acceleration. I felt it while driving the truck during elk season, and the miss was not constant (like a single cylinder miss), but it did happen every time it was under acceleration while climbing in the mountains.

There doesn’t seem to be a loss of power and no noticeable smoke. The truck starts up and idles fine.

I read many of the other threads I could find where miss or misfire was mentioned, and they would suggest an injection pump or timing issue, but a local shop he talked to said they doubted it was injection pump related since it would affect all cylinders and it would be hard to start.

I raised a concern about taking it back to Central Motive Power based on what he said happened, but he said they seemed to have done a good job diagnosing the previous issue. He’s also considering a NAPA Auto care shop (Extreme Auto Repair) in Parker.

Finally, does anyone have experience with either of these shops or have a recommendation for aother good diagnostic diesel shop in the Denver metro area?

Thanks!

roughstock

Will it miss if you just rev the engine while in neutral, at a stop? or does it need a load to do it?
Also seems odd to need inj pump and injectors at that few of miles.

patdaly

I can't help you with a shop out there, but if you can do minor stuff yourself, perhaps we can figure this thing out.

First is to tell us how long it has been since the fuel filter has been changed, also, has the pre-filter ever been cleaned?

We need to find out what fuel pressure the lift pump is providing, and if low, is it the pump or the overflow valve...... At 142K you should never have had to touch the thing, unless the IP was one of the ones with out of round barrels.

Also, if he takes it to one of those shops, be sure and bounce what they are telling him off us before they would do anything goofy...... Lots of really good BS detectors around this place.

EDR

Thanks for the replies gentlemen.
Roughstock - The truck doesn't have the miss if you just rev it.
It must be under a load---going up hill or pulling the trailer.

Patdaly - I'll pass the question on to my Dad, and I'll also ask what originally caused him to have the new injectors and pump installed.

BarryG

I have used both of these shops multiple times in past years but not recently(at least two years for either of them). When I used them I was satisfied with their work and no problems.
http://www.maxtorqdiesel.com/contact-1
http://douglascountydiesel.com/

EDR

Hello again.

My Dad didn't address the injector question (so I'll ask him again), but he did say that the fuel injection pump was leaking oil at the throttle shaft on both sides and at the shut down shaft.

He didn't mention anything about the filters or fuel pressure so I'll ask him to check and respond.

Thanks again for the responses.