Engine/Transmission (1994 - 1998) starts and dies

[PFeick]

Well the truck had been sitting for 4 days it started right up, I moved maybe a truck length in reverse and then it died. Would not restart at first. I checked the fuel selenoid (it was up) and cranked it with some pedal and it fired erratically, and evenually it started. Sputtering at first (air) Truck has 150,000 miles, and is stock, original lift pump etc. Truck has a 1/4 tank of fuel. It has done this to me before under similar situations in this driveway. While parked for the weekend in a different a area, again nose uphill 1/4 tank, started fine, stall and difficult re-start. Ran fine once running. I have changed fuel filter less than 1000 miles ago. I capped fuel tank with shreader valve and pumped air in to check for leaks between tank and filter and couldn't find any. It is driving me nuts, and shaking my confidence in the engine. I am thinking about droping the fuel tank to check pickup and replacing rusty fuel and brake lines in the process.



And on another note. Truck is loud. I try to ignore it but when the toll attendent tells you it sounds sick it is embarrasing. I turned the idle down as low as it goes and and determined the #3 cylinder to be the culprit. I swapped #1 injector with #3 and the noise did not move. With the #3 squirting oil the engine purrs, quietly. I bought the truck with 110,000 on it. Previous owner just put a new turbo on it. I don't remember it as being as loud then but it is possible the cylinder was scored then. Of couse the turbo dying and blowing motor oil and worse material into the #3 might have caused overheating scuffing to begin with. Or it could have been dreaded plastic piston cooling nozzles. Next oil change I am sending a sample out to be tested. On the bright side truck runs well (other than the occasional intermittant stall on startup).



Run it till it dies swap in a used engine?

 

[EBansberg]

It sounds like the dying problem is just from air getting into the system. It is fairly common and may be from the fuel heater. Mine is doing the same thing and I'm planning to remove the heater and install a new gasket to see if that cures it. Joe G did an excellent write-up on the fuel system and common problems, send him a pm if you'd like a copy to help troubleshoot the problem. Next time it sits, try pushing the fuel pump button a few times to pressurize the system, it should run without dying if I'm guessing correctly. As for the rest of the stuff, not sure where to go. How was the turbo killed so quickly? Has the power been turned up and are there gauges to make sure it isn't burned up?

 

[PFeick]

I do believe it is air. The second time it stalled on me I changed fuel filter, and I swear it was only half full of fuel. Recently with the cooler temperatures it has been a little sluggish in the am, but didn't die. It doesn't seem to want to go above 1500 rpm until its been down driveway (1/4 mile uphill) and warmed up a bit. Temps at night have been in the high 20's low 30's. I haven't started plugging it in yet. I live in northern nh and have considered overhauling/ fuel heater and strainer. Might as well repace lift pump while your in there. I did read in tdr mag. they short out etc. Volt meter certainly swings on start up so one of the cold start features is working.



Previous owner was in process of getting divorced I don't think he was plugging it in regularly due to living temp living quarters. Turbo bearing failure due to cold oil starvation. That is my best guess on why turbo was replaced. Truck obviously did some towing with gooseneck hitch. For all I now they were towing the budweiser draft horse trailer. Needless to say I should have looked into turbo failure in more detail. No I do not believe injection pump has been turned up, and I do not have any extra guages. I put exhaust system on because it seemed easier and cheaper than replacing muffler and missing tailpipe. I adjusted valves and replaced cover gaskets recently, it reduced highway drone.

 

[EBansberg]

the voltage swings are the grid heaters in the air intake cycling on and off. the fuel heater can be removed with no ill effects. the lift pump is most likely good although it does occasionally leak some air and if so the o-rings on the plunger need to be replaced. I would be surprised if they were towing something that heavy with stock power but maybe. If the turbo failed due to cold oil starvation, that might explain why cylinder #3 is no good. Is there any sort of boost elbow to allow higher than stock pressures? what happens when you try to go above 1500rpm when it's cold?

 

[PFeick]

I start it up. Air temp around 32 degree f. Let it idle for a minute and drive down driveway into low point and back up to access road. Going up power is weak, doesn't seem to want to take fuel. After another 1/2 mile it goes away. I think I need to change thermostat. A fuel pressure gauge wouldn't be a bad idea either.



The rubber boot on the lift pump is cracked and fell off at one point. I zip tied it back on. I carry a spare lift pump with me.

 

[surfbeetle]

Change your fuel supply and return hoses at the engine above the trans. They are notorious for going bad. I've changed mine several times over the years. Larry B's sells a kit with marine grade hose that lasts longer than standard hose. Also, check your vent on the top of the fuel tank, it can get clogged and cause a pressure situation where it can suck the fuel out of the pump. Had this happen as well. The other thing can be the fuel heater below the lift pump. Get your fuel supply pressure issues resolved first then look at your injection pump and injectors if you still have issues.

 

[PToombs]

Take the fuel heater out, throw it away, and let us know how it is after that.

 

[PFeick]

Thanks for the suggestions. I have larry's fuel hose kit. I have not installed it yet. I do remember a bit of a vaccum/whoosh last time I removed fuel tank cap. Fuel heater/strainer is due for service.

 

[wcjp]

On my 96', my air problem was a loose fuel preheater cap. Also, the fuel preheater gasket was bad. Next was the soft line to the liftpump. This soft line had extreme dry rot. I cut it open to discover I could see light through the sidewall. I also changed out the fuel supply/return. The lift pump wasn't in stock with any local dealers. Had to run a long line in a lazy loop but avoid the steering shaft.



The fuel lines above the transmission are easier if the starter is removed. With the starter out it's a good time to swap out the starter contacts from Larry B. If you haven't swapped the contacts it's time. Pay now or alot later.

 

[STeichert]

I just worked on a buddy's '96 tonight that would only run for about 30 sec and die. We took the Fuel heater off and threw it in the trash, it was sucking air. The truck runs as good as ever. Those fuel heaters are no good. I took mine off of my '96 years ago because of similar problems. I live in very cold country and no problems

 

[PFeick]

Yeah the fuel heater is a culprit. At the moment I am knee deep in a brake job. Truck has been running fine. Of course I haven't left it sitting for 3+ days and then tried starting it either. I'm replacing rear wheel cylinders with 1 ton units, new shoes, rotors pads and front wheel bearings. I wrecked one front wheel bearing wacking the rotor with a 4lb sledge out of fustration. Last winter I rebuilt the front u-joints and re-assembled the hub to knuckle joint with generous anti-seize. However they were still a pia to remove. I wrecked another 14mm socket with the loosen and beat the bolt technique. Oh well. When I have more time I'm going to drop fuel tank and replace steel fuel/brake lines and paint rusty areas of frame. I bought front wheel bearing from napa, I hope they last as long as the dodge version. (160,000 miles). The new rear wheel cylinders were of the offshore variety... I doubt the new front wheel bearings will say timkin on them. Rotors fins were rusty and would not pass inspection. $400+ worth of parts, it could be worse. Hope to be back on the road tomorrow.

 

[PFeick]

Truck died 300' from driveway, had enough speed to coast into parking space w/trailer. Primed fuel filter and it re-started. I have ordered heater puck, fuel guage, strainer service kit and overflow valve.

 

[fest3er]

Change your fuel supply and return hoses at the engine above the trans. They are notorious for going bad. I've changed mine several times over the years. Larry B's sells a kit with marine grade hose that lasts longer than standard hose. Also, check your vent on the top of the fuel tank, it can get clogged and cause a pressure situation where it can suck the fuel out of the pump. Had this happen as well. The other thing can be the fuel heater below the lift pump. Get your fuel supply pressure issues resolved first then look at your injection pump and injectors if you still have issues.

Second this. Both the hoses and the metal line can and do rot through given enough time. If air is getting into the fuel system quickly, the number one suspect is any line prior to the lift pump, which will rapidly suck air into the fuel system. If air is getting into the fuel system only after sitting a day or three, the number one suspect is then the return line(s). It took 12 years for my fuel lines to rust through. But they did, and I had EXACTLY the same problems.



A couple years ago, there was a nasty fuel leak; the return hose behind the fuel filter finally failed. This year, it began to start very hard all the time, eventually got to where it wouldn't stay running unless it was turning 1500 RPM; the line feeding the prescreener rusted through near the quick-connect fitting. I installed rubber line to replace this rotted line. Then it would be hard to start after sitting a few days, and there was a fuel leak (which became treacherous in rain after a while); the return line rotted through. Again replaced the steel line with rubber. Truck starts and runs almost like new now; I really should check the overflow valve; I think there's too much pressure in the return line.



If you smell #2 fuel under there, you have a leak; no ifs, ands or buts. Get your special glasses (if you need them) and a good light and look everywhere for fuel outside the system; you'll find it and you'll likely be able to trace it back to the leak. Crawl under and over the truck. Lay cardboard and sheet foam over the radiator/latch/engine and lay down on there so you can get your head nearly down beside the block. You'll find the leaks.



Also, not having much power when cold is completely normal. It can take a half mile (unladen truck) for the cylinders to warm up enough to let the engine burn enough fuel to build enough boost to work the engine and heat it up.



As to the prior turbo failure, I seriously doubt it failed because of cold oil starvation, unless it spent most of its life in the arctic; were this true, there would have been reports of hundreds of thousands of turbo failures. More likely it failed because oil coked up on 'superheated' bearings and parts, especially if the truck was 'rode hard and put up wet'.

 

[Missouri Mule]

Both times I had trouble starting it was the rubber fuel lines (first time return line cracked, 2nd time supply line cracked) after I primed it would start and run fine. It has never started and died because of air in the lines (except maybe when I was doing a fuel filter change ).

I would check your fuel heater for air leaks.

What is your idle when it is cold/warm?

Have you checked out fuel shut off solenoid/realy?

 

[PFeick]

When truck died I popped hood and checked fuel selenoid, I swear it was down but when cycled ignition it popped back up and stayed up. At the time it died I was working 2 blocks away so batteries were taking a beating, I may have shut off ignition to save juice/amps. I have replaced relay once before. Boot is in good condition. I have looked for diesel leaks and haven't found any obvious ones. I was looking at fuel heater plug when the electrical power went out (high winds/fallen tree). Power came back on this evening. After looking at all the fuel connectors and line types I am considering what others have done that is replace all fuel lines with marine grade rubber. Fisheriessupply.com has decent prices on shields brand. I looked at top of fuel tank gooseneck line and it is rusty also. Not sure if I can clean it up or just replace it too. Truck is idling around 850 rpm. At 110,000 when I bought truck it would stall if you cranked wheel w/ac on etc. I raised idle, above 32 degrees it will start no pedal/extra fuel needed. I tore out 1000 sq/ft of asphalt and the truck dragged it away no problem so it isn't afraid of work. If only I could get it to idle without all the knocking and banging!

 

[Missouri Mule]

If you didn't do it this way. Set idle whlie in drive and a/c on. The service manual recommends 750-800 rpm but a lot of members set it higher so 850 would be OK.

 

[PFeick]

Installed fuel gauge today. Truck idles high around 850rpm for winter. No gas pedal needed when plugged in or warm starting. Fuel pressure at idle is 20-22 psi. Rev it up and pressure drops to 18 briefly and increases to 25 psi. I did not pinch off return line yet. Tomorrow I will clamp return line where it's rubber by the firewall and re-check fuel pressure.

 

[PFeick]

Pinched off fuel return line at fire wall. Pressure gauge held steady between 22-25psi. No noticable increase.

 

[Missouri Mule]

When you pinched off return line did pressure drop to 18 when you rev it?

Or did you rev it ?



Pressure not going up much would point to the lift pump but at idle 22 to 25 is Ok put fuel pressure should increase when you rev to 2000 rpm.



I would pull the overflow valve and check it and its spring out.

 

[PFeick]

Ok, I installed new overflow valve on injection pump return line. Fuel pressure at idle 22psi, up to 30 psi when you rev it up. Yes fuel pressure does drop to 18 before increasing to 25 at mid-throttle. When I first ran it with new overflow valve pressure was a steady 25 easily hitting 30. It dropped a bit after running it around 10 miles and rechecking at operating temp. Replaced both batteries too. I ordered rubber fuel hose elbow from dodge dealer. Next I will replace all rubber fuel hoses and clean strainer, replacing o-rings and new fleetguard heater puck. While searching for dropped sealing washer I noticed that fuel selenoid boot is torn. Add that to the list...