This will blow your mind... 90 Ram D150..

[wjackman]

Alright guys check this out please.. its gonna be kinda long but im a diesel mech in the Marine Corps and i cannot figure it out to save my life... I have a 1990 Dodge Ram D150 with at least 225k miles. My Dad bought it brand new and it has never had any major problems and barely any minor problems. Well about 2 weeks ago the truck just started randomly dying on me while driving and/or idleing. Originally I thought that it was just my fuel filter so i replaced it with no result. Then i decided hell, i will give it a tune up... so I gave it a full tune up. When i started it up the engine ran like a charm and i even drove it for about 15 min and it was fine. When i pulled back into my parking spot i let it sit running for about 3 minutes before it died again!! So i figured i would resort to changing the fuel pump (located in the tank). So... I dropped the gas tank and accidently broke the return line on top of the fuel pump sending unit. I went ahead and put the new fuel pump in and then i started calling around trying to find a new sending unit ( the part where the three lines and electrical outlet hook into). I couldnt find it anywhere not even through Dodge.. they said its not a wear and tear item and they dont make it/carry it. So anyway i ended up rigging it up to where it would work and i put it everything back together and bolted the tank back up. I know for sure that even though it is rigged up it should definately be working. Well anyway now i am not even getting fuel to through the two injectors (throttle body). I have no clue.. help! Thanks. Email wjackman @ ec (dot) rr (dot) c o m

[zerko]

Does the pump run briefly when you turn the key on? Did you replace the fuel hose inside the sending unit? They crack and alow air in the line. There is a TSB for that . The ASD relay on the inner left fender controls power to the fuel pump, injectors, and coil. Check to make sure you have power to this relay. You will most likely have to shop the scrap yard for a sending unit. Just trying to remember an old "Jimmy-Rig" I did once- Try running a positive wire from the battery to the positive term of the coil. This should back feed power to the injectors and pump. It got me home once! Another problem could be the pick-up in the distributor ( suddenly dies, and needs a few minutes before restart) . They are bad for going in these trucks. Unfortunatly, the easiest way to replace it is to remove the dist.

[wjackman]

Yeah i can hear my pump kick on when i turn the the key over into the on position. I am fixin to go buy a haynes manual on it and just start testing all the fuel system connections. I appreciate the reply and the pictures... i printed them out. Ill let everyone know when i figure it out. (I think its time to get a new daily driver... 10mpg.. 17m one way to work!)

[Chump]

I also would say the pickup assembly in the distributor.
Try running error codes off the computer and see what pops up.
As for the broken plastic nipple, looks like 1990 was all by itself for fuel pumps and modules. The way the top plate/nipples was replaced is by ordering the complete fuel pump module under Mopar part# 52004636...very pricey.
You might try here for a used one www.car-part.com or www.junkyarddog.com


Displaying & Reading Trouble Codes

Accessing Codes
With Check Engine Lamp

To start the function, cycle ignition switch ON-OFF-ON-OFF-ON within 5 seconds and any stored fault code will appear. Check engine lamp will display the code by flashing on and off. There is a short pause between flashes and a longer pause between digits. All codes displayed are 2 digit numbers with a 4 second pause between codes. The lamp will flash until all codes are displayed then 55 (end test) will appear.

[wjackman]

Well I got it running again (I had accidently hooked the return/supply lines up backwards...switched em out and it fired right up but it is doing the same thing that it was doing originally now.It just dies while I am driving and then has difficulty starting back up. I just got back in from replacing the coil because i thought that maybe it was overheating but it is still doing the exact same thing. I have replaced the entire fuel system except for the whole throttle body itself and its still doing the same sh##. I really do not think its the throttle body. Do you think it could be the ignition switch causing it?? :gr_patrio

[Chump]

Did you change the pickup assembly in the distributor and run the error codes?

[wjackman]

Not yet... I am gonna try it out and see what it says though. Up until now I thought that these were just minor problems and that i could easily fix them but im starting to wonder now!

[Chump]

The pickup assemblies in the distributor do get heat sensitive and can fail intermittently. If the pickup fails then the computer sees no pulses and shuts down the ASD relay. The ASD in turn shuts down the fuel pump and the ignition system. This is the way it is designed.

[zerko]

When it's running, try tapping the side of the distributor BODY ( NOT the cap) with a screwdriver. Sometimes it will cut out right away. If so, the pickup is bad. I have done this, and it worked on both my trucks. Thanks Dad!