Engine/Transmission (1998.5 - 2002) Wierd Code and acting up (Long post)

[KKohagen]

2002 Ram, HO with 6-Speed (NV5600), mostly stock except for aftermarket air filter, PacBrake, and Air Dog Fuel Preporator.

Checked for codes, 1693 (ETC companion code) and 0230 (Fuel circuit).

I have had an Air 100 system installed for a few years. The stock harness triggers the relay to start the air dog pump. It had done the normal 1-2 second bump when the key is first turned to ON. It would also do the ~25 second if turned to Start and then moved back to ON without the engine starting.

Fuel Gauge showing 14-16# when the fuel pump runs.

Recently the fuel pressure has started to bounce around. Then while in Big Bear (on the way up the hill it started) I was seeing close to 0#. Then if I S/D and restarted the fuel pressure would show ~14-16# at idle with the transmission in neutral and clutch out still good fuel pressure. Then placed in gear and ease out the clutch anywhere from 0-15#. Engine did not sound any different. I then assumed it was probably the sender, Westach electronic one.
Got home and started to trouble shoot. Checked lots of wires for continuity etc... The wiring to the Air Dog still works fine, when I jumper through the removed relay the pump starts up. Checked continuity on the wiring going to the stock deutch connector, showing continuity. Then rigged a jumper to check the relay, relay is fine. Checked voltage on the lines coming from the deutch connector and show0-3 volts maximum while triggering the normal bump and the 25 second bump. Changed out the fuel pressure sender to rule that one out. Still no dice.

I installed a toggle switch to at least turn on the pump before starting so I could drive to/from work until I could finish trouble shooting.

Today I tried to further identify what is going on.

Now with clutch pedal pressed in , and relay installed (toggle switch removed), the pump will bump the normal 1-2 or the 25 seconds if I turn to start. Volts showing ~12. 6 to 12. 8; however if I release the clutch pedal the pump turns off immediately. I reinstalled the toggle switch to turn the pump on, to prevent VP44 damage if the engine starts - Relay is pulled.
Checked voltage on the connector (to see if the ECM was sending voltage). Normal bump got the ~12 volts, bump start (25 seconds) got the ~12 volts all with the clutch pedal pressed in. At anytime release the clutch and the voltage drops.
Bumped the starter got the good fuel pressure and the voltage (AIR Dog was already running) and then while waiting for the pump to turn off I actually started the engine. (Clutch is still pressed in) Engine running, good volts, let out the clutch (trans in neutral) and the voltage drops off ~1-2 and down to zero. Press the clutch back in ... BINGO ~12-13 volts... let it out down goes the voltage.

So what can I do to get the pump to start like it is supposed to with the normal after-market relay? I do not want to buy parts just to find the problem. Air dog works if I use a jumper or a toggle switch across the relay harness. Switched out this relay with spares that I have acts the same.

Can't figure this one out. Any help would be appreciated. I have cleaned a lot of the grounds just in case, but got very surprised today when the clutch made the voltage change.

 

[JLandry]

The P0230 DTC indicates the ECM is sensing something isn't right with the lift pump circuit and is shutting down the circuit as a protective measure. While it seems crazy (under the circumstances since you're only using the ECM to power a relay) some fault must be triggering this... or the ECM is bad.

Based on what I see in the wiring diagrams, the ECM can't know what position the clutch is in. I'm wondering if there's something wrong somewhere in the wiring harness... like maybe a short or open circuit is being created when the clutch is released.

The next thing you're going to have to do is to thoroughly test the lift pump wiring harness to see if you can figure out what the ECM is seeing that's causing it to turn it off. If you'll send me your email address via PM, I'll send you that section from the Dodge Diagnostic Procedures Manual. It's too big to attach here.

Best regards,

John L.

 

[hcole]

KKohagen,I have a 2002 that the in tank conversion lift pump wouldn't satisfy the motor under load so I installed a Holley red pump on the chassis inline with the supply line. I wired it a little different from everyone else. I picked up the signal from the injection pump fuse under the hood at the fuse block and used that to power a plugin relay mounted beside the fuse block. The Holley comes right off the battery. I now have the Holley coming on as SOON as you turn the key to on and can have instant pressure and let it run as long as I want without starting the engine. The Holley will pull right thru the in tank pump. I have been operating like this for a year or so. Runs good at 12-14 lbs and will only pull down to 9-10 under wide open throttle. Works especially well in cold weather when the fuel is thick and needs a little circulation.

 

[CAPTPHIL]

Trouble shoot the neutral start switch on the clutch pedal.
Good Luck Capt Phil

 

[Bob Cochran]

You can jumper out the neutral switch and see what happens. About the only thing electrical in the clutch mechanization. Perhaps there is a short in the wiring in this circuit someplace. I am only guessing sure hope you find something.

Trouble shoot the neutral start switch on the clutch pedal.

Good Luck Capt Phil

 

[Sticks]

Check for rub through in the harness under the dash near the clutch pedal, and see if a harness came loose underneath by the slave cylinder as well.

Ignition switch maybe?

 

[KKohagen]

I have not disregarded all of your responses. I have been very busy at work.
The MIL light has gone out sometime during a very long commute home this week. I am still using the toggle switch to control the AirDog.
I have not seen any rubbing on the wiring or harnesses, but I will go over them closer later this week.

Thanks again for all of the suggestions. I will keep you all in the know.

 

[KKohagen]

A few days after my last post I fell down some stairs while helping a friend move. Ended up cracking 2 ribs and messed up my shoulder. I am finally able to laugh without pain, most of the time. I cannot look down into my engine compartment, let alone trace the wiring issue.
I still am using the toggle switch, however the MIL keeps coming on and off almost in synch with the weather outside.
Will let you al know when I get this figured out.

Thanks again all for the suggestions.