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My dodge b1500 1997 van 3.9L 6cyl. The van cuts off-replaced many sensors - any ideas?

It happens when i come to stop at a light or after i stop (for gas) and crusing down the highway it starts to cut off and i have to restart on road.

I replaced:



Fuel pump - (in tank) It was going bad anyway as it turned out (no fuel pressure - not up to spec) so this was good

TPS throttle position sensor

Ignition Coil

Distributor Coil

Idle Air Cntrol

Rotor/distbutor

Plug wires

Plugs

Air filter.

Of course, It runs much better as these DID need changing but, it still stalls. Seems to be no way to predict conditions that occur to cause the engine

shutdown. I noticed the lights did go out once when it was about to stall. But that doesnt happen every time.



I dont have enough $ to replace all the sensors and / or the EMT computer (unless you know that is what is wrong).

The van usually starts back up but sometimes with difficulty. Sometimes I must turn off the key and try again to get it started. Otherwise, if I start

cranking it then it doesn’t fire up. It’s like it is not getting fuel, but, see details above for what I have replaced.



I Had it scanned @ AutoZone and no codes come back now. it failed while on an analyzer and they still couldnt figure it out. I was told its a relay so, I switched all the identical relays around but no luck.

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The parts I want to try next are expensive so I am trying to narrow this down:



Ignition Switch

Crank position sensor

Cam position sensor

MCU (computer)



PS. I did scan at Auto Zone and it returned the coil. I erased the codes in case it happened again and it has stalled hard a few times but now returns no codes. so, what returns NO CODES that could cause this van to stall?

The components in the fuel system that you haven’t changed are the fuel pressure regulator, injectors or the fuel filter (or is it in the fuel tank and got replaced with the pump?).

Question: You say it just cuts out (even on the highway). Explain exactly what happens.

Does it suddenly stall (as in: NO spark), or does it stutter and stall (as in: out of fuel)?

You mentioned the coil but haven’t changed it, right? This is a 6cyl so that means three coil packs.
This may be an ignition system (perhaps a bad module?) fault.

Have you had any problems with the key cylinder in the column? Sometimes over-loaded key rings break the parts inside and cause electrical connection faults.

Obviously I’m no tech, I’m just suggesting other possibilities.

I too noticed that you did not mention replacing the ignition module. The next time you can crank without a start connect a spare spark plug to one of the coil wires, ground it, and see if you have spark while someone else cranks. What I do during trouble shooting is to have a clamp on timing light available and connect it immediately to #1 sparkplug wire on a no start condition to see if I have spark. If I do I check to see if the spark is anywhere near the Top Dead Center for #1 cylinder.

If you do have spark but still no start, use a little spray ether into the intake to see if the engine will catch. If so look for something with the fuel system.

So carry that spare spark plug, timing light, DVM, and can of ether in your diagnostic kit.

What the nice person at Auto Zone was talking about was the ASD relay (Automatic Shut Down). It controls electrical power to the fuel injectors and ignition. The horn relay is the same as the ASD relay, I think. This problem is a tough one. It may be best to take it to someone more experienced.

Hi My dodge, I know it’s been a couple of years since you had this challange; did you ever rectify it and find out what the culprit was? I have a b1500 2003 van 3.9L 6cyl, runs good except once in a while it is rough as if you know when you have bad gas(in your tank)especially going up a hill at about 30mph-40mph; it seems like it might stall;(like it is not catching) I replaced my pcv valve;air filter; and spark plugs; I’m leaning towards maybe the fuel injectors are clogged and need to be cleaned out.what throws me for a loop it does not happen all the time.I was thinking you might have some hindsight now that I do not have. thankyou for your time, I remember in the past I had the same symtoms on another car and changed the fuel filter and it worked like a charm;no more rough running) but pep boys is telling my it is part of the fuel pump assembly which is in the tank; that does not sound like a good engineering move to me.should be an easier access to the vehicle owner Frank

I had similar problems with mine (same year and engine). Replaced one electrical part after another. Each time I replaced a part the code would show another electrical part being the culprit. Finally found out it was the ECM. Found a place in Chicago on Ebay that rebuilds them and warrants the rebuild for life. Cost me about $120. Takes 5 minutes to remove it. You send it in. They fix it and send it back to you. 5 minutes it’s back in and no more sporadic problems!