I ran my 2000 CHEV K3500 out of fuel and now have trouble

[OBE]

I have had this truck for a year. It runs like a champ. I tow junk cars to the shredder. I pull a 5th wheel camper, an Econoline 10 Ton Equipment Trailer modified to carry two cars, and a 5 Ton Lowboy (35' long) I've gone across the scale (at the shredder) with 22,000 lbs. It walks the PA mountains with that camper with no strain. This truck runs great!

One day it shut down, as if it ran out of fuel, but the gauge read HALF. A check revealed a bad sender on the AUX tank, with holes and rotted tubing and a total mess. It was full but when the front tank called for fuel the AUX would have none of it and then the front tank ran bone dry.

I've owned three other diesel tow trucks but bought each one new so I didn't work on them when they needed repairs. I'm totally uninitiated where diesels are concerned. I'm retired now and we closed down the junkyard but I still have this equipment. I need to get it (the truck and the two trailers) all cleaned up and sell them. In my ignorance, I "figured" I could make a ONE-TANK truck out of a TWO-TANK truck. Then I could take my time and try to locate a whole setup from a junkyard as long as it was in good shape. The first place they towed me to wanted to put in a new tank ($900) and sender ($575) with $99 per hour labor. I can't afford this. I'm ALREADY buried in this equipment to where I'll NEVER get my money out of it!

I disconnected the hoses between the tanks. I unplugged the pump between the tanks. I filled the front tank and after a lot of cranking, it started. The garage charged me for changing the fuel filter, so I knew that was clear. I could see inside the tanks and they were clean and the fuel looked okay. I did crank the heck out of it, bleeding the air release on the top of the filter repeatedly. It appeared as though I had been successful.

I drove it on the highway for about 100 miles over a three-day period. It ran fine, as usual. Then one day it shut off.
I suspected it had run out of fuel again, but it shouldn't have, since I had filled the front tank and only driven about 100 miles. I pulled the filler hose off and I could see fuel in the tank. I put another 5 gallons in thinking it might be below the take-up level, or something (I don't know)
I cranked and cranked it and it got to a point where it was starting right-up but then dying when I released the starter (ignition switch)

I kept trying and trying because I was certain that it had somehow run out of fuel again. One time I hit it and it started up just like nothing was wrong. This truck usually jumps-alive, with only the slightest cranking, even thru the winter months. There was no rough idling or bad running or anything that seemed wrong. I thought I had gotten lucky again! I set out to drive it home. After about a mile, it shut off again, and I had to call AAA to tow it home.

I read a post that said that starting then stalling is a common problem with GM 6.5 Turbos. It said that if a certain DTC wasn't present then it was a 95% certainty that the PMD was bad. Now mind you, I didn't even know what all these acronyms stood-for before this event.

I went to Harbor Freight and bought an OBDII Reader. It showed a P0126 & P0236 DTC, neither of which was mentioned as relating to this problem. I ordered a Remote PMD Kit ($407 with the shipping) and the truck started and ran. I drove it to work for a whole week then on the weekend it shut off while I was driving down the road.

I seem to have really compounded my problem by running on the main fuel tank, making it very difficult to apply "the scientific method" in troubleshooting the problem. The AUX tank still has the rotted-out sender in it but it's not connected by hoses to the main tank.
Someone said I still need to have the AUX sender connected electrically, so I put the plugs back on (but the hoses are still disconnected)

I've been reading about GROUNDS and TESTS I need to perform, but I've come to the conclusion that I'm going to have to buy a new sender and hook it all back-up before I can check for any other faults. Please excuse my rambling but i am at wits-end with this darn thing!

[racer55]

Your problem sounds more like a bad ignition switch.

As for the rear tank problem a new sending unit and lines is all you really need,but do not use the strainer sock from the aftermarket sending unit-reuse the stock strainer or remove it completely and add an inline screen between the sending unit and rear lift pump.

Here are threaded barb fittings that can be used to replace the metal line with diesel rated rubber/neoprene lines:

papco part number 905-352 =3/8*4 inches 16mm nut

papco part number 905-350 =5/16*4 inches 14mm nut.

P0126 Insufficient ECT for Stable Operation :could be a faulty temp sender in the thermostat housing or bad connections or stuck open thermostats or even low coolant?

P0236 Turbocharger Boost System :could be a bad boost sensor,cracked or broken vac lines,boost solenoid or vac pump issue?

[Snowbound98]

Check your fuel pressure. When u say it starts while cranking but shuts off when u let go of the switch sounds like your lift pump shuts off which would be a sign of a faulty oil pressure switch on the back of the block behind the intake manifold. U can try jumping the pump with a hot wire and see if it stays running. Most of the time the pump will pull the fuel but then your overworking your injection pump. The electric oil pressure switch can be going bad and that's why it ran for a week then started acting up again. Oil pressure switch is cheap. 1 1/16" wrench to take it out. I can't see why it wouldn't run with just running on the front tank unless its sucking air. And if your rear tank was that bad anything that was in the rear tank may have been transferred to the front tank. I've also seen bad fuel caps cause this. If the fuel is pumping out and the cap won't let air in the tank it hydro locks the tank. Try removing the fuel cap and see if it sucks air and then try to run without cap on and see if that makes a difference.

[racer55]

Check your fuel pressure. When u say it starts while cranking but shuts off when u let go of the switch sounds like your lift pump shuts off which would be a sign of a faulty oil pressure switch on the back of the block behind the intake manifold. U can try jumping the pump with a hot wire and see if it stays running. Most of the time the pump will pull the fuel but then your overworking your injection pump. The electric oil pressure switch can be going bad and that's why it ran for a week then started acting up again. Oil pressure switch is cheap. 1 1/16" wrench to take it out. I can't see why it wouldn't run with just running on the front tank unless its sucking air. And if your rear tank was that bad anything that was in the rear tank may have been transferred to the front tank. I've also seen bad fuel caps cause this. If the fuel is pumping out and the cap won't let air in the tank it hydro locks the tank. Try removing the fuel cap and see if it sucks air and then try to run without cap on and see if that makes a difference.

Good thinking and you may be right,but for 96+ trucks the OPS is only a secondary power source for the LP-the ECM and LP relay do the main control and power of the LP.

What may also be a more important factor is if the fuel balance module is acting up?

[racer55]

Wiring diagram here:
http://www.thedieselpageforums.com/tdpforum/showpost.php?p=273597&postcount=8

[OBE]

Fuel Balance Module, eh? That would also account for the strange phenomenon happening with the fuel gauge too (maybe)

When I turn the key to ON, the fuel gauge goes to a little less than full. Both tanks are full now, since I bought a new sender for the AUX tank. I cleaned the tank out real good! It wasn't too dirty. I vacuumed it out and ran a clean rag around inside. It was spotless before I put the sender in. OBTW, I encounterd a strange problem: the unit didn't want to sit comfortably in the hole. It seemed as thought the sock and tubing was "bottoming out" and I had to coax it into place with a little pressure. I noticed a small discoloration in the bottom of the tank where the sock intake was sitting on the bottom. Does that sound normal?

I don't know if the fuel will transfer from the AUX to the MAIN tank because I haven't driven it. I don't know if my installation of the sender was a success although it doesn't appear to be leaking. It starts right-up and in about 20 seconds the gauge "snaps" down to "E" It does this every single time. I have replaced the PMD. (I don't really even know if it was bad!

All the while (now) it runs normally until it does this: It starts to "chug" as if it has a bad "miss" and then shuts off. Now before I say the next symptom please let me explain that this motor never smokes. The exhuast is invisible of any color or much odor. As it begins to chug, the exhaust turns dark; not black, but it is visibly darker as if it was running "rich."

As I said, I am starting it all the time but I don't dare take it anywhere for fear of breaking down again. Maybe my shut-off-then-won't-start problem doesn't exist anymore. Since it's cheap, I'll replace that oil pressure switch and maybe that fuel balance thing. Is that part very expensive?

[OBE]

racer55: thanx for the diagram but I don't understand them. I don't know how to read it. :(

[Warren96]

an easy test to make for you to make to isolate the fuel system is to bleed air from the top of the fuel filter. When it stalls, does air come out? Another thing, You can get codes read for free at a lot of parts stores,I happen to use Autozone.

[OBE]

I bought an OBDII reader at Harbor Freight.

[OBE]

How about that difficulty I mentioned when installing sender. Has anyone encountered that? It went in but I did have to "force" it a bit, and with a delicate instrument such as the sender, I don't like the "feel" of that!

I haven't replaced anything else since my last post. I have several other projects running and I have had to work on those.

[racer55]

Sometimes they are a tight fit and with a new o-ring it can be very tough to get the locking ring started in place.

[Fishnfool]

Back in 2003, my 96 6.5 was having an intermittent stalling/no start problem. Truck would either die while driving then not want to re-start or would just not start - it would crank over but not run. A peculiar symptom associated was that I would lose dash warning/idiot lights upon stall or when truck would not want to start.

I found that if I slammed the steering wheel up & down through the full tilt range, sometimes the dash would light back up and the truck would start & run. Was told by someone here on The Diesel Page that I needed to replace a part of the ignition switch assembly, p/n D1481C, and that should fix the problem. Got the part from my local Chevy dealer and had it installed and the problem was fixed.

In 2007, truck once again started randomly dieing with associated loss of dash indicator lights and refusal to re-start. This time, jarring the steering wheel column did no good and the truck would only randomly start if the key was turned on and off or I left it sit. Indicator lights would sometimes sit there and flicker faintly at times.

After checking all my grounds, battery connections, fuses, etc, the problem turned out to be the ignition switch going bad AGAIN after only 4 years. Replaced the switch and have not had any problems. I tore the old switch apart and three of the contact levers had moderate pitting/oxidation - apparently enough to cause my stalling/starting problem.

Thanks Chevrolet for yet another poorly designed component requiring replacement way too often http://www.dieselplace.com/forum/images/smilies/thumbsdown.gif

Not sure if the same part fits your 2000 K3500 but here it is at Amazon for $108 with free shipping

http://www.amazon.com/ACDelco-D1481C-Ignition-Switch/dp/B000C9RTBM

[OBE]

Thanx to racer55 for the support. It eases my mind to know that it IS a tight fit and that it wasn't me doing something wrong.

Thanx to fishnfool for the tip about the ignition switch problem. Racer55 said it might be that part back in the beginning of my posts.

I appreciate all the advice and support.

[ginger743]

Back in 2003, my 96 6.5 was having an intermittent stalling/no start problem. Truck would either die while driving then not want to re-start or would just not start - it would crank over but not run. A peculiar symptom associated was that I would lose dash warning/idiot lights upon stall or when truck would not want to start.

I found that if I slammed the steering wheel up & down through the full tilt range, sometimes the dash would light back up and the truck would start & run. Was told by someone here on The Diesel Page that I needed to replace a part of the ignition switch assembly, p/n D1481C, and that should fix the problem. Got the part from my local Chevy dealer and had it installed and the problem was fixed.

In 2007, truck once again started randomly dieing with associated loss of dash indicator lights and refusal to re-start. This time, jarring the steering wheel column did no good and the truck would only randomly start if the key was turned on and off or I left it sit. Indicator lights would sometimes sit there and flicker faintly at times.

After checking all my grounds, battery connections, fuses, etc, the problem turned out to be the ignition switch going bad AGAIN after only 4 years. Replaced the switch and have not had any problems. I tore the old switch apart and three of the contact levers had moderate pitting/oxidation - apparently enough to cause my stalling/starting problem.

Thanks Chevrolet for yet another poorly designed component requiring replacement way too often http://www.dieselplace.com/forum/images/smilies/thumbsdown.gif

Not sure if the same part fits your 2000 K3500 but here it is at Amazon for $108 with free shipping

http://www.amazon.com/ACDelco-D1481C-Ignition-Switch/dp/B000C9RTBM

I want to replace my ignition switch due to intermittent electrical problems. The shop manual shows that removal of the steering wheel and the " upper and lower shrouds " is required , Just about requires removal of the steering column. It shows this switch mounted on the column on the opposite side of the turn signal , " lever " .

I've seen posts like this one mentioning replacing the Ignition Switch but I can't find a description on what that involves. I've seen mentioned here that it's on the steering column but the switch referenced in the above link requires work as I described above .

Have I got this about right per the shop manual ?

Thanks for any clarification .

Jerry

[a5150nut]

It sounds like they are descibing the key tumbler. On my 94 the switch is a small box on the lower end of the steering colum connected to the key cylinder with a rod running don the colum. Look for a small box with a bundle of wires pluged into it.

[ginger743]

That's the description that I've read here previously that's why I was questioning this. When I look at the switch that the Amazon link takes me to it looks like the switch I described that's located opposite the turn signal lever.

Glad I didn't order that Amazon switch without checking here first !!

I'll check it out.

I sure appreciate the help, thank you very much !

Jerry

[Yukon6.2]

Hi
On my 97 it is on the top of the column.
I had to remove the steering wheel and plastic around the column.The pain is finding all the fasteners without breaking them.I had to take the switch out of a donar so that helped some.You will need small torx sockets or a good selection of metric and standard 5 and 12 point.
There is a tool to press the locking ring plate down to get the clip out.I made one.
It was definatly the problem when i changed mine.
Good Luck
Thomas

[ginger743]

Thanks Thomas , appreciate the help,

I think the post that suggested the Amazon switch was referring to a different problem. My instruments aren't failing but I have other electrical stuff being intermittent like the interior , " courtesy " lights losing power along with my door locks and alarm system losing power intermittently.

I fixed the bad splices in the after market alarm system door locks but now I have a different door lock symptom along with the interior courtesy lights and the alarm system intermittently failing .

As old as this truck is I figure if this doesn't fix my problem that's ok knowing the failure rate of this part, it's probably due anyway.

Jerry