So, I may have asked this on this forum before, but the problem is clearer to me know, but the cause of it isn't.

So, when I fire up cold, in the morning or after a few hours, everything seems to run great, meaning power is fine, low to no smoking, pulls hills, I can give it fuel at 60 mph and still obviously accelerate.

However, if I shutdown, even for a few seconds, and then fire up again, I have a lack of power issue that I can't get to "go away." Smoking becomes much worse, my top end on flat ground is 60 mph, I can't pull small hills in south Georgia! My mpg is low as hell too, averaging 22, when it should be 35 or so!

Now, curiously, once I was able to regain "normal" power by backing off the fuel pedal and then giving it fuel again gently, but I've never been able to replicate this.

It seems as though the heated engine is causing something to not operate properly after shutdown. Fuel cut solenoid? If so, how can I check this and where is it?

Could timing be the culprit? No knocking either. My tranny needs some work though. Could the tranny cause it by inducing drag or something?

FYI, it drives fine if I never shutdown, for hours even, on road trips.

The motor is original and the mileage is about 137K. It's not a turbo, just a regular c223.

Any ideas?

Thanks,
Dean

It sounds very similar to the problem I'm having. In my case I suspect that the settings on the pump is incorrect, thus the governer kicks in when it's not supposed to.

The other, which I still have to look at, is a leak on the fuel line between the pump and the tank.

The fact that your smoking increases, indicates that either your engine is not getting the air, thus the mixture is more rich, or calibration on the pump that is out.

It could also be that one of the solenoids on the pump does not open up properly when it's hot, due to heat expansion.

Gosh, don't go diddelling around with the IP settings. Check for hose connections, frayed/split (even the tiniest cracks in the ends) and see if the screen that is in the banjo fitting is clogged. Banjo fitting on the IP. Be EXTRA careful to keep even the smallest spec of dirt OUT of the IP/lines.
Is the gasket onthe intake manifold OK..bolts secure?
How abotu the fuel tank...vented OK?
And the filter, gasket not snagged or folded over, lines secure.
If you are in No. VA let me know and I'll drop by to give you an assist.
Eric
:-)

Hi Guys, new member from United Kingdom. Sorry if I'm late on this thread but can you guys with lack of power issues tell me what models you are running and which diesel motor?

I have 1993 Isuzu Bighorn 3.1 tdi auto which is essentially a Trooper grey imported used from Japan into the UK along with many thousands of others over the past 5 years. May be able to assist with a bit more info. We have no info and support on the Bighorns in the UK as most dealers refuse to acknowledge them as "proper" Troopers, which is quite insane considering the amount of business they are turning away. So, we have to help ourselves!

Best etc....

Hello. The fix to this problem sounds very complicated.......but it is not, just time consuming.......

First thing to do is fix a container under the hood to hold about a half gallon of your favorite injector cleaner (this is more so to clean the internals of the IP) remove both the fuel inlet hose and the fuel return hose and place them in the container........crank the engine and use up almost all of the cleaner and in this time rev the engine up several times as well as turn the engine off and restart several times..........

After this, remove the injectors and clean the injector port in the head of carbon (should be about a 5/16 to 3/8 clear hole)......cleaning the injectors and setting the pop off pressure is a excellent idea at this point........reinstall the injectors...........

Now starting at the IP where the metal fuel line connects, remove the banjo bolt and clean the screen, remove the fuel filter mount and clean it (it has a one way valve in it, make sure that you can only blow one way through it....................new fuel filter.........

Now remove the fuel tank top and blow compressed air back through the fuel line to the tank.

Replace all fuel hoses with new clamps as well............

Fill the new filter and hose to the IP with fuel.............

Start the engine and go for a long drive......stop......and immediately loosen the fuel tank top listening for a "rush of air" into the tank.........if so, replace the top......

If the problem is still there.........on the fender well side of the IP is the Cold Start Devise.......you can best see it from under the fender well.........in the center of the CSD is a round plug with a 11 MM allen...........remove the plug.........there will be tension on the plug.......be careful of the shims and spring....................remove the spring and shims and reinstall the plug being careful of the "O" ring.................now on the top of the CSD you will see a banjo bolt and metal line that goes up to the fuel return hose..........remove the banjo bolt and clean it out..........go for a drive and vary the engine rpm a lot.....................now reinstall the spring and shims........................you May have to repeat this a few times to free up the timing advance....................

Set the IP timing...............

enjoy,
crossbones