Injection Pump Timming

[ryno]

I have a 1995 6.5 TD Pick up with a power chip, 3" exaust and K&N filter. It began stalling a while back, and I eventually replaced the injector pump and PDM. After doing so the engine ran fine, but made a popping sound or a dull knock which can only be heard from inside the cab. This sound also does come and go randomly. It burns a little more black smoke, and seems to run a little rouph periodically when in 5th at low rpm. Recently the Engine has started cutting out once it warms up from a cold morning start. It is almost as if the pump turns off and then on quikly. This has been getting worse very quilkly and is happening more often. I am wondering if poor pump timming would be the cause of all this, especially the engine cutting out. The truck has a secondary fuel pump therefore rulling out the oil presure switch. The fuel filter has been changed many times lately, I have wiggled all the electrical lines and cleaned battery cables. Wonder if the PDM could be shot after only 1000km's? Thanks!

[charliepeterson]

Welcome aboard!

Go up to the top of this page and hit "search", type in stalling. You will get lots of information. If you still don't see what you need then add to your question and someone will pipe in with some help. Any and all questions can and will be answered here.
Try to give all info on the truck such as work done and mileage.

Your stalling or engine miss fire issues have been covered.

[ryno]

Thanks, I went through all the post that the search returned with no luck. As I have replaced the injection pump, PDM, filter, and lift pump, the only things I am not sure on are;
- Poor Timing
- Bad ingition switch
- Air in the system
- Fuel Shut-Off
- Pump or PDM already toast
As I only did the repair on the PDM and pump a 1000kms ago, I am leaving that fault until last.
As for the ingnition switch I have not checked it,
but would I not get other issues such as other accessories acting up, or lights comming on/off? Seems orginally the truck was only stalling in the mornings, although it has gotten worse now.
As for air in the system, that will be the next step at this point
Somewhere I read about a fuel shut off, is there something other that the oil presure switch as I have a secondard fuel pump that will produce presure even if the lift pump quites.
Last is timing. As the truck has acted a little funny since the pump and PDM replacment I am wondering if it would be possible for timming to cause the issues in the previous post. Has anyone ever had there Injection Pump Timing out of wack, if so what did the truck do?
My truck is a 1995 TD 6.5 with 240,000km
5 spd, power chip, 3" exaust, K&N filter, Exaust Brake. Thanks again!

[charliepeterson]

When the truck seems to shut off then turn back on it's called an engine skip. The usual issues are fuel supply not adequate enough for the current demand or air in the fuel delivery. Each has it's own qualities.

Some members have had issues with the Ignition switch on the '95's. I think some keys are sporatic speedometer and unusual transmission shifting. Power goes from the ignition switch to the transmission.

I have seen first hand where a PMD failed only two months after installation.

Engine timing won't make the truck stall but can make for longer starts and poor fuel mileage and performance.

My conversion tables are a little rusty but I would guess 240,000km is more than 120,000 miles and your out of warranty?

I personaly think it's a very good idiea to remove the PMD from the Injection Pump and mount it on a remote cool plate. John Kennedy has a nice extension harness which plugs into the OEM harness and lets you mount the cool plate almost anywhere you want.

I would lean towards the PMD failing but do everything else first. I have my PMD on the top of the intake manifold for almost six years now and I've lost only one driver. My timing is set at -1.94TDC with high flow injectors and have so far had no issues.

Good Luck

[Turbine Doc]

Fuel delivery is crucial,

I had a problem a couple of weeks back when pulling 7000 lb load my truck wanted to flat out die above 25 mph up small hill, it was a country back road so no problem with going slow.

The odd thing was with no trailer and empty bed truck ran like raped ape, not a single miss. Called my buddy RATDOC and he suggested fuel delivery problem.

Inj pump can pull fuel solo without lift pump but it struggles when loaded down. As a possibility of problem cause, I changed my fuel filter even though it was only 5K miles old, hooked up to the trailer the following weekend; and you would have thought I dropped a new engine in the truck.

I was able to pull that same load 60 mph up the same hill that I struggled to make 25 previous weekend. (must have got a bad slug of fuel somewhere)

I also installed a temporary gage to the fuel filter bowl drain and monitored fuel lift pressure, of course this was after I changed the filter (hindsight 20-20 rule applies here).

The results were a real eye opener; with a new filter engine at idle 6 psi pressure in bowl, steady state driving 4 psi, punch it from 40mph instant drop to 2 psi, now with the partially blocked filter I changed, I can only imagine how bad I was starving the pump.

In some of the lost threads there used to be references to a term "fish biting", never knew what it was until above scenario. Loaded truck jerks like mad until you back off the throttle, as if you have a whale on the end of a fishing pole fighting to get loose, feels like engine is rapidly shutting down and restarting like a bad miss in a gasser ignition system.

PMD could be the culprit, but when mine went bad
(knock on wood, no problems 1.5yrs, since mounting on FSD cooler as Charlie recommends) the truck would shutdown completely, intermittent shutdown while driving from my experienice I would attribute to lift delivery problem, check your fuel filt, lift pump, and lift pump power as well.

I've placed an order for primary filter Racor and will also be installing spare 2nd lift pump to make sure I don't drop to 2 psi when loaded.

[JohnC]

If the PMD acts up enough to affect performance, the PCM shuts the engine down. The reason is that the PCM no longer has control over the throttle, so it's a safety issue. If the engine is not shutting down it's unlikely the cause is the PMD (FSD).

[ucdavis]

Fuel shut off (FSO) is a vertical solenoid on front left of IP. It is a rare failure, but it happens. You can tell if FSO kicks open on start by having assistant turn key & feel the solenoid bump w/your hand on it; that doesn't help when on the road & I'd love to see a diagnostic for it underway.
The in-line fuel pressure guage is a good start. If pressure spikes when engine hiccups, FSO is suspect as it may have just shut down denying IP fuel. FSO is an easy change-out; just pay attention to cleaning around it B4 removal to avoid contamination of IP.
I wouldn't rule out lift pump failure even w/a backup; no diagnostic in a '95 (later units set a DTC). You can also check this w/fuel pressure guage, but it will drop instead of rise.
Charlie is right on- it has to be fuel delivery; only question is whether its mechanical or electrical failure.
You didn't mention codes. Check DTC's (http://www.thedieselpage.com/members/trblcode.htm) & post whether any or none; either one is another clue.
Check Member's Area, scroll down to Reference Section & read article on Stalling; this is applicable checklist method for your problem.
Good luck.

[ 09-25-2003, 12:59 PM: Message edited by: ucdavis ]

[ryno]

Thanks for all the knowledge, but still no dice. Today the truck would not run for more than a minute. When working on it today it would stall quickly and then sometimes start again easily and then others not at all. When driving the check engine light would only come on when the engine shut down for a long period of time but then turn off once the engine fired again. The code that came up was 35 (short pulse). I checked all hoses and could find no crakes or leaks. I removed the new fuel filter and it is still clean. I checked fuel pressure and always have at least 6lbs. I even cracked open the fuel filter drain and fuel would flow freely from it when the truck stalled. I removed the oil pressure switch and the lift pump plugs and the truck acted exactly the same. As I just replaced the pump it looks as though I should just get a new one under warranty, but if anyone has any other ideas please let me know! I still am not sold that it is not a fuel delivery problem to the injection pump. But that probably because I don't want to do the job again!

[whatnot]

Could it be air in the lines or plugged return line? Did you try replacing the hose that comes out the top of the IP with a clear one and watch for air bubbles and fuel flow?

[charliepeterson]

Codes #35 and #36 are for "pulse width", how long the Injectors were open delivering fuel. These codes won't make the truck stall. They can be the beginning of the Injection Pump going South though.
If you have fuel pressure when idling, new filter and plenty of fuel then the PMD is failing. This condition will get worse to the point where it won't run.

[patrick m.]

if you have not replaced your ign switch, then you probably should, the 95 models are known for have trouble with them. (Gas or diesel).
as far as your eng miss/skip/off-on, that is the classic symptom for oilpress switch.
lets go over what we know.
the inj pump and driver are new(that doesnt mean they are perfect, but "new" puts them last on the list)
the fuel filter is new
the lift pump is new
the ign switch is old
the oil psi switch is old.

replace them both! its money well spent because they both will give you trouble if they are not the cause of your problems now.

[ucdavis]

ryno,
If I was being you I'd
1) replace ignition switch as suggested; these are mileage dependent & I assume you've got enough miles on your rig to warrant, whether that's the immediate trouble or not. If that does not do it,
2) replace the pmd by plugging in a spare fsd (i.e. don't go to the bother of putting it on the IP. If it seems to work, put the fsd on a heatsink on the manifold or in front of radiator bulkhead w/wiring extension. If new fsd doesn't do the fix,
3) replace the IP. I was getting 35/36 & did #2 & it did nothing. The pump was bad @ 25,000 miles. I saved the old PMD for a spare since it may not hve been bad. New pump, runs like new.