nonextant
Junior Member
- Joined
- Feb 2, 2020
- Posts
- 1
- Reaction score
- 0
- Location
- Colorado Springs, CO
- Ram Year
- 1998
- Engine
- 8.0L V10
Hi,
I am new to the forum, but will hopefully be an active member.
I own a 1998 Ram 2500, V10, 2wd extended cab, and it has been pretty reliable so far until.....
I went to a meeting last Monday and the truck was running fine. I came out after and I turned the key, but let go before the engine had fully fired up. It idled roughly and bogged down when I gave it some gas. I turned it off and tried to restart, but it just wouldn't fully catch... very poor idle, died when giving it gas. I tried a couple of times with the same result.
I opened the hood and pressed in the Schrader valve on the fuel rail. It seemed like the fuel shot out with a little bit of pressure (about 3 feet) but it sputtered quite a bit, as if there was air in the line.
I attempted to start again, but it would just turn over and not fire. I checked the Schrader valve again and this time got a tiny hiss of air and nothing else.
I replaced the Fuel Pump and ASD relays with know good ones. (tested in the horn relay socket)
It started fine on starter fluid and as far as I know it had the original fuel pump, so I ordered another one.
After getting it up on jack stands, I was able to drop the tank in the parking lot and change out the pump, but in the process, damaged the plastic fitting on the fuel line.
I was able to pick up a new fuel line at my local junkyard and hooked up everything on the ground to test it. I turn the key, and engine turns over but doesn't start.
On a whim, I hook up the old pump to a 12v drill battery and it whirrs into life, so I run a wire from the battery to the positive pin on the new pump. I hear it activate and have pressure at the fuel rail. (guess I didn't need to buy a pump after all)
I know that the fuel relay is activated from a signal from the PCM but I'm not sure how to test the circuit.
I split apart the relay panel to look underneath but was unable to spot any damaged wires or burned components.
One thing that confused me is that a lot of forums talk about jumpering pin 30 and 87a to bypass a fuel relay, however on my truck, there is no wire to the 87a socket in the relay socket, so I'm at a loss as to how this system works. from memory it seems like 30 was always hot, 87 had low voltage (dim test bulb) but I think it was also all the time.. I have to check again. no 87a, I can't remember the other 2 pins.
In order to get it out of the parking lot, I cut the fuel pump power wire where the loom runs outside the frame by the drivers door, capped off the power supply end and ran a new wire from the fuel pump end to the accessory power switch to the radio. The truck runs fine like this for now, but I need to add a fuel pump switch so I can cut power to the pump with the key on.
I wan't to return this circuit to the way it is supposed to be, but I'm not sure where to look for the problem. I am completely open to any advice.
Lessons learned:
Always check that your pump is actually dead before dropping the fuel tank. (You can use a test lamp if you don't have a multimeter, but will need two people unless its dark enough to see if the light comes on from the cab.)
When dropping the tank, make sure unplug everything before you drop it. (Unless you have really long arms, climb underneath and reach above the frame just forward of the rear axel)
Strap bolts are 15mm and if you have the 34 gallon gas tank, there is a crossmember that must be removed, Also 15mm
Fuel line holder bolts are 13mm. If you have the 34 gallon tank, make sure you install all the bolts before lifting the tank back in place or you will not be able to reach the rear bolt location.
No local chain auto parts stores sell a fuel line repair kit that reduces from 5/16 to 3/8 fuel line. The outlet for the fuel pump is larger than the actual fuel line. If you try to piece something together using rubber high pressure hose and barbed fittings, it will leak. I spent just over 22 dollars on repair kits, and ended up just getting an entire fuel line from the junkyard for 9 dollars.
Thanks for reading all of this, and I appreciate your responses.
Mark
I am new to the forum, but will hopefully be an active member.
I own a 1998 Ram 2500, V10, 2wd extended cab, and it has been pretty reliable so far until.....
I went to a meeting last Monday and the truck was running fine. I came out after and I turned the key, but let go before the engine had fully fired up. It idled roughly and bogged down when I gave it some gas. I turned it off and tried to restart, but it just wouldn't fully catch... very poor idle, died when giving it gas. I tried a couple of times with the same result.
I opened the hood and pressed in the Schrader valve on the fuel rail. It seemed like the fuel shot out with a little bit of pressure (about 3 feet) but it sputtered quite a bit, as if there was air in the line.
I attempted to start again, but it would just turn over and not fire. I checked the Schrader valve again and this time got a tiny hiss of air and nothing else.
I replaced the Fuel Pump and ASD relays with know good ones. (tested in the horn relay socket)
It started fine on starter fluid and as far as I know it had the original fuel pump, so I ordered another one.
After getting it up on jack stands, I was able to drop the tank in the parking lot and change out the pump, but in the process, damaged the plastic fitting on the fuel line.
I was able to pick up a new fuel line at my local junkyard and hooked up everything on the ground to test it. I turn the key, and engine turns over but doesn't start.
On a whim, I hook up the old pump to a 12v drill battery and it whirrs into life, so I run a wire from the battery to the positive pin on the new pump. I hear it activate and have pressure at the fuel rail. (guess I didn't need to buy a pump after all)
I know that the fuel relay is activated from a signal from the PCM but I'm not sure how to test the circuit.
I split apart the relay panel to look underneath but was unable to spot any damaged wires or burned components.
One thing that confused me is that a lot of forums talk about jumpering pin 30 and 87a to bypass a fuel relay, however on my truck, there is no wire to the 87a socket in the relay socket, so I'm at a loss as to how this system works. from memory it seems like 30 was always hot, 87 had low voltage (dim test bulb) but I think it was also all the time.. I have to check again. no 87a, I can't remember the other 2 pins.
In order to get it out of the parking lot, I cut the fuel pump power wire where the loom runs outside the frame by the drivers door, capped off the power supply end and ran a new wire from the fuel pump end to the accessory power switch to the radio. The truck runs fine like this for now, but I need to add a fuel pump switch so I can cut power to the pump with the key on.
I wan't to return this circuit to the way it is supposed to be, but I'm not sure where to look for the problem. I am completely open to any advice.
Lessons learned:
Always check that your pump is actually dead before dropping the fuel tank. (You can use a test lamp if you don't have a multimeter, but will need two people unless its dark enough to see if the light comes on from the cab.)
When dropping the tank, make sure unplug everything before you drop it. (Unless you have really long arms, climb underneath and reach above the frame just forward of the rear axel)
Strap bolts are 15mm and if you have the 34 gallon gas tank, there is a crossmember that must be removed, Also 15mm
Fuel line holder bolts are 13mm. If you have the 34 gallon tank, make sure you install all the bolts before lifting the tank back in place or you will not be able to reach the rear bolt location.
No local chain auto parts stores sell a fuel line repair kit that reduces from 5/16 to 3/8 fuel line. The outlet for the fuel pump is larger than the actual fuel line. If you try to piece something together using rubber high pressure hose and barbed fittings, it will leak. I spent just over 22 dollars on repair kits, and ended up just getting an entire fuel line from the junkyard for 9 dollars.
Thanks for reading all of this, and I appreciate your responses.
Mark
