Newer injection pump, low on "power"

[mooseracing]

For lack of a better term I use power but I don't really feel it is that. I have a '94 IDI that I put a sealed reman injection pump on (from Uhaul parts) during the winter of 2013/2014. I've put about 15,000 miles on it since than but I notice to do 45mph or more it is almost an all or nothing affair now. I have to have the pedal almost all the way down to maintain speed, but not all the way down, very fine line. If I have it all the way down I, the truck is still accelerating and I can relatively easily hit 90mph on the freeway. Also when all the way down there is that slight black smoke which is the same as when I timed it.

I recently replaced the air filter and fuel filter since they hadn't been done since the previous year. I also replaced the throttle cable as the plastic was broken on mine for a few years and was causing some binding.

Any ideas here?

 

[icanfixall]

Are you able to reach rpm above around 2800 rpm? Also you say the engine was timed when the pump went on. How was it timed. And what is the timing in degrees.

 

[IDIoit]

get yourself a fuel pressure gauge.
i had the same issue when i replaced my IP, (among others)
the fuel gauge revealed that i was only at 3 psi with a stock lift pump
i put a electric fuel pump in it, cranked it to 6 psi and cured it

 

[mooseracing]

Are you able to reach rpm above around 2800 rpm? Also you say the engine was timed when the pump went on. How was it timed. And what is the timing in degrees.

I'll have to check RPM on the way home. Pump was timed with the recommended here way of the little ferret box and an adjustable timing light. Don't remember the degrees (maybe 8ish), I would have to look around here as I followed the write up. I Would have to get the toys out to check and see where it is at.

get yourself a fuel pressure gauge.
i put a electric fuel pump in it, cranked it to 6 psi and cured it

I was thinking maybe lift pump, but the black smoke at WOT, made me think not.

 

[IDIoit]

black smoke will not tell you if you have the required fuel pressure.
it only tells you that youre not burning all of the fuel at WOT.

like i said, get a gauge and see where you are at....
a 10 dollar mod will help you in a variety of ways!

 

[mooseracing]

So in park i can bring the rpm right up to the orange line no issue, about 3400. On the road in first it gets to about 3100 before it shifts.

I picked up a new fuel pressure kit since I couldn't find my adapters. I didn't trust gauge for low pressure, since it went to 150psi. I didn't realize the adventure it would be to find a low pressure gauge. All special order. I found a tiny inline one and put it on my test set. 3psi at all rpms.


Edit, forgot to add it is definitely alot worse in the cool mornings (40's), until the truck has some good heat. By worse I mean almost wide open just to maintain 50-60mph

 

[OLDBULL8]

Put your truck info in your signature, including the trans and turbo if you have one.

Black smoke= IP retarded. Check timing, 8.5 to 9.5 BTDC with turbo 10 to 11.5
Check IP throttle shaft for WOT. Hold foot peddle to floor, see if IP throttle shaft is at WOT. Takes two persons.
3400 RPM with no load is not a good WOT RPM check.

 

[mooseracing]

Wow how time flies when you have 0 free time.....

So I had a road trip coming up and I wanted to take care of a few things. I have a few slow seeping return lines and a partial kit on the shelf, so I replaced the passenger side, as it drives my OCD nuts to have things leak. I also tracked down my timing tools, it is still sitting good, 9/9.1 @ 2080rpm.

It was about 4hrs of highway yesterday, same issue, basically nothing from 25%-85% pedal. Could still accel up to 90 or so, just have to maintain 60-80 at just under wide open.

Picked up another fuel pump awhile ago, but it is sitting on the seat still.

 

[chris142]

Isn't 3400 a little low? Mine will spin up the the red 3800 under load even

 

[typ4]

Dually was doing this, advance system in pump was done. Just like a Detroit 2 stroke," heap big smoke, no power"

 

[icanfixall]

Some of our members have experienced issues with u haul pumps. Seems they sat on the shelf a long time. Try removing the fuel filter and refilling it with atf. then get the engine running till the engine sound changes. This tells you the engine is running on atf. Shut down and allow to osit over night. the atf will unstick and issues that may be in the pump. Next day run the hell out of it flushing out any stuff in the pump.

 

[riotwarrior]

Search Tech 101 diesel purge....do that let stop let sit overnight n fire in AM...should be clean after that!

 

[mooseracing]

I'll try the ATF this weekend, my luck we will get a fire or medical call in the middle of the night so it won't get to sit.....

One thing I noticed on my long trip that I forgot to mention as well, I think the advance is sticking on return. I say this as it will only happen at heavy throttle (highway speeds or parked), if for example you are cruising and someone pulls out to pass in front of you, you let completely off then get on the pedal, there is a 5-10 second delay where the engine RPM picks up and gets loud (like a cold start or heavily advanced timing), no accel then kicks back to normal. I was able to replicate this while in park jumpstarting my other truck.

 

[typ4]

If you dont have an air intrusion issue, your pump needs rebuilt. Properly.