Engine/Transmission (1994 - 1998) Low power on a 1995 12 v

[JPS]

I agree about being a PITA. jps

 

[RHestand]

Have you ever replaced the 2 small fuel lines that are located on the back of the engine? One is the supply line & the other is the return. They just bridge the hard lines (6-8" long) and are for damping the vibration. These hoses can look fine but suck air thru cracks which fuel will not leak out of and cause loss of power. Do NOT use regular fuel line from auto parts store or you will just be replacing them again. Buy USCG approved marine grade fuel line and you will never have to replace them again. The thickness of the hose wall is 3-4 times that of regular hose. Use all stainless steel clamps and have a good 1/4" drive ratchet set.
Note>be sure to have some bandages for your hands, arms & fingers as they are a PITA to change, hence the marine grade hose.

Ditto with crabman re: PITA. Band-Aids were my friends!
Also I bought a kit (Geno's?) that had plenty of the good USCG hose and SS hose clamps. The difference about mine though was it was leaking fuel (Very small leak. Just enough to keep the whole truck smelling like a diesel spill, and it was a PITA to find!) instead of sucking air.
Ray

 

[surfbeetle]

Did you ever check the Fuel Shutoff Solenoid? It's really very easy to check, just reach down and if you can pull it up any measurable amount then you have a problem. You can even use some wire like a piece of a coat hanger to hold it all of the way up. Drive it and see how it responds, just realize if you have it tied up, you can't shut the truck off since the plunger won't be able to cut the fuel. This can easily be your restriction. It could be a bad relay or bad solenoid. Again looking back at my original post to you, you need to look at all of these things. If your boost line from the turbo to the injection pump is bad, then your injection pump won't meter out any more fuel either.

 

[JPS]

No "surfbeetle", I have not checked the fuel solenoid. Really have not had time to do much of anything the last few days. Hope to get at it soon!!! Thanks for the reply. jps

 

[Bob4x4]

You should have about 25 psi and see it go up to Bout 30 at hi rpm. The governor springs will give you more rpm when every thing else is good

 

[GAmes]

Has anyone have info on the spring that was used in the injection pump? Something about upping the rpm when really stomping on it. I think later it was discovered the same thing could be done with washers. Talked to a guy at Geno's garage, said he had never heard of the spring. I have one, not installed, sure I bought it at Geno's. I remember the cost, $125, if I am correct.

You are referring to a governor spring kit. It is used to allow the engine to rev over 3000 rpm, so if you want to do that you need to fix the problem at hand. There should be two sets of springs in the kit. The washers are a band-aid, not very reliable mod.



When I had my pump in the Bosch shop (also a performance shop) the owner removed my 3k GSK and reinstalled the stock gov springs. For my towing and low rpm usage he proved to me they are a lot better. Tq comes in at a lower rpm and if I need to I can still accelerate to 3200 rpm. They are a good mod for racing, and a handy tool while towing to bridge the 3rd to 4th gear gap in a NV4500. They are not the panacea that they are made out to be by some people.

 

[FParisi]

With my old '95 the GSK was usefull in that it prevented de-fueling that started at about 2200RPM. Maybe more usefull with the old auto tans than with a 6-speed. My understanding was that it didn't effect low Rpm fueling so no reason to not have it if keeping RPMs low.

If I remember, there was a lot of talk about the overflow valve spring getting weak/compressed + allowing too much fuel to return, reducing fuel to burn. Something else to check/replace if not already done.

 

[JPS]

Air filter check ok, different fuel didn't seem to help. Did discover from a family member, it had done about 95 MPH on a try out. Didn,t know that. Seems like I have a lot of checking on things to do. We're working on it, slowly!!! jps

 

[JPS]

Bob, Checking fuel pressure, I have about only 10#. This is at both ports on the Primloc fuel relocation kit. Now what??? jps

You should have about 25 psi and see it go up to Bout 30 at hi rpm. The governor springs will gie you more rpm when every thing else is good

 

[Bob4x4]

with the pressure gauge in place pinch off the fuel return hose momentarily,if the pressure shoots up the overflow valve has failed if not time for a new fuel pump (as long as the fuel strainer is clean)

 

[JPS]

Thanks for the quick reply,Bob. Fuel strainer looked clean. Are you talking injection pump or is the a mehanical pump pushing fuel?? jps

 

[Bob4x4]

Lift pump on the block

 

[MLee]

Did you ever check out the suggestion to check the overflow valve pressure thing above? I thought I had read that you had replaced it. If not then check out the TORQ TEK over flow valves. These guys are adjustabile, and a good price.

 

[JPS]

MLee, no I have not checked overflow valve yet. Did order one from TORQ TEK. Not here yet. Where is the hose to overflow to squeeze for checking overflow?? TIA jps

 

[Bob4x4]

It runs behind the injection pump and down the firewall

 

[MLee]

MLee, no I have not checked overflow valve yet. Did order one from TORQ TEK. Not here yet. Where is the hose to overflow to squeeze for checking overflow?? TIA jps

Slide under your truck on the left side, behind the tire and along the frame you'll see TWO RUBBER HOSES that are attached to two hard lines coming from the tank,forward toward the engine. These go up toward the bottom of the intake manifold, under the rear of the injection pump. One will go up to where the fuel filter was, and the other to the over flow valve. The one that connects to the OV is the return line.

good luck hope this helps.

 

[JPS]

Thanks MLEE, that really helps!! Plan on working on it today!!! jps

Slide under your truck on the left side, behind the tire and along the frame you'll see TWO RUBBER HOSES that are attached to two hard lines coming from the tank,forward toward the engine. These go up toward the bottom of the intake manifold, under the rear of the injection pump. One will go up to where the fuel filter was, and the other to the over flow valve. The one that connects to the OV is the return line.
good luck hope this helps.

 

[JPS]

Well I put in new overflow valve, better pressure at idle, on the road, zero pressure. Thinking new lift pump now. Have a hard time spending the money for Fass or other electric brand. What is the opinion on here. Stock power is good enough for me. I would think the mechanical should work. TIA jps

 

[JPS]

Thought about screen in tank, is there such a thing? Can you pull it out with out dropping the tank. Hooking it with a piece of wire ,maybe??? jps

 

[GAmes]

Yes there is a screen in the tank, at the bottom of the module. Lifting the bed if you don't have a tool box. aux fuel tank or hitch rails is easier than dropping the tank. I have all three, so I drop the tank. Really not that hard of it is nearly empty.