Engine misses?

[kulwap]

Okay I need to provide some background first. I spent the last four years in Sacramento, CA and had stalling problems on my 6.5. I replaced the PSD and put in a Heath cooler and haven't had any problems for a while now.

Recently we moved to Spokane, WA and made a trip to see some family in Canada. The drive to Canada was uneventful, but while returning and on the highway the engine seemed to start missing. On the move up, my father-in-law drove the sub while I drove the our VW-TDI and he commented to me that the tranny seemed slightly hesitant a couple of times.

I don't know if it was the same problem we both experienced, but when I was driving in Canada, I downshifted from drive to 3rd in order to rev the engine higher and maybe clear any transmission or injection problems. This seemed to work, and we didn't have any problems for the rest of the trip 400+ miles.

Well the sub is the vehicle that my wife drives, and she has had the problem return while running errands. I have searched "engine misses" on the forum but only found two topics, one about the injector pump (mine was replaced at 80K and I now have 120K on the sub), the other was for a problem with the tranny speed sensor. There wasn't a follow up post showing that the speed sensor problem was resolved. Any thoughts?

[BrentN]

Kulwap,

Sorry to hear about your problems and I am not sure to what magnitude your "miss" is. You may infact have a miss due to the pmd,inj pump, lift pump, speed sensor, but also consider this:

Initially, once fall came, I thought I had a miss too...turns out though, that slight miss or bump, is just my ac compressor kicking on and off becuase I am in defrost mode. I especially feel it around 55-60.

You may indeed have problems and the defroster issue may not be it...but try it and see..Turn your heater control off of defrost and wait..then turn it back on.

I am sure others will weigh in as to other causes, but, since you were up in colder climates, I thought that you might be using your defrost more than you were before.

Good Luck,
Brent

[patrick m.]

i would check out the lift pump, make sure it is running while the enginr is running.
if not, find out why it is not running, check oil psi switch, fuses ect. (check for power at the lift pump first.)

[fastcat800]

As someone told me a couple of months ago when I had a missing problem, "It has to be a fuel problem as a diesel has no ignition system". Open the tee valve for the water seperator drain when ideling. It's in the top front of the engine by the thermostat housing. If fuel comes out within the first couple of turns you have a working lift pump, if you get no fuel either your lift pump or your oil pressure switch is bad. If you don't get fuel within two turns stop. I kept turning mine 4-5 turns until the truck quit and then it was a pain to get the truck restarted. This is the quick and easy fuel pressure test if you don't have a gage to stick in the line comming off the tee (3-5 psi). If you have no fuel pressure have someone crank the truck while you hold your hand on the lift pump (on the frame rail under the drivers side door). You will feel it thumping while the engine is cranked if it is good. If it pumps when the engine is cranked the OPS is bad if there is no fuel pressure when running. My problem was the OPS. Power to the lift pump comes through the OPS when running and directly from the key when cranking. If you have fuel pressure next change your fuel filter. After that it is time to look at the injector pump.

[nigeljones]

Kulwap

When was the last time you changed the trans fliud and filter. I get a slight mishift/hesitation around 50,000 miles which I now recognise as it's time to change the filter and fluid.

I also agree with the others, lift pump,OPS as I have had all the typical issues we get with the trucks. smile.gif

[kulwap]

Thanks for the input. I will check it out this weekend and post the results.

[kulwap]

Okay, as I explained earlier in this thread, I just moved. I have been very busy getting the new house set up and the garage is a mess so I haven't even had a chance to do a lot of work on either vhicle.

Anyway, the Sub stalled while my wife was driving it yesterday and once she got it going again the "Check Engine" light was on. So, this morning before work I got out the OBD II code reader and hooked it up. The code I pulled was P0251, Injection Pump Fuel Metering Control "A" Malfunction (Cam/Rotor/Injector). Before I got the code I was thinking that it may have something to do with the pump, but I wasn't sure, I 'm still not sure even with the code. I would like some more input before I try to drop a new pump into it. Any advice?

[CareyWeber]

Originally posted by kulwap:
Okay, as I explained earlier in this thread, I just moved. I have been very busy getting the new house set up and the garage is a mess so I haven't even had a chance to do a lot of work on either vhicle.

Anyway, the Sub stalled while my wife was driving it yesterday and once she got it going again the "Check Engine" light was on. So, this morning before work I got out the OBD II code reader and hooked it up. The code I pulled was P0251, Injection Pump Fuel Metering Control "A" Malfunction (Cam/Rotor/Injector). Before I got the code I was thinking that it may have something to do with the pump, but I wasn't sure, I 'm still not sure even with the code. I would like some more input before I try to drop a new pump into it. Any advice? kulwap,

Do a search on P0251 and check lots of things before replacing the pump. I got a P0251 last year and everyone said time for a new pump. Well I found some wire rubbed bare where the ECM harness goes from the engine compartment to the cab once I repaired them my truck was fine and that was a year ago or so and about 12K miles.

Carey

[BrentN]

My P0 251 was solved by changing my fuel filter and purging. FWIW. Brent

[Bigg R]

My brother's 98 6.5 had that same code.A new injection pump was the fix....sorry!!!

BIGG R

[gwaidman]

I was having a 'miss' every now and again. At first I thought that my foot had slipped of the pedal. As it happened again and again I started looking harder. Pulled off the fuel filter assembly and found that I had a leak at the fuel heater wires. Quite common I hear. Replaced that (comes with a new filter) and I have not had any problems. Hope this may help you out.

[kulwap]

Thanks again. I have a Heath FSD cooler installed, and I emailed Bill. He suggested it might be the filter harness unit. I replaced that and it seems to run better, but has still stalled for my wife (never for me) again.

I did a couple of quick things that were suggested, I opened the fuel valve that is near the front of the engine and fuel did come out, and I looked around at the grounds and fuses. Nothing visibly wrong there, so next on the checklist for me is to replace the fuel filter, and actually clean the grounds and pull the fuses.

One last thing, if I can't find the cause myself, and if I don't get more time to look into it, does anyone have any experiance with a diesel shop in the Spokane area?

Thanks again.