Air Dog 150 quit working....

[whitexc]

Hey folks. New to the forum. I have a 2002 24V/Auto. I have pretty much gone through the truck from front to back, including paint a cple years back. She looks good and always gets compliments. The truck is very reliable for the most part (a few hiccups but that comes with age). I tow light with it - 25' camper in the summer, a 20' pontoon boat every so often and a 2 place enclosed sled trailer in the winter.

Black 2002 short bed 4x4 w/ 211K on the clock
Edge Juice W/ Attitude
AirDog 150 - that quit!!!!
Blue Chip VP44
RV Injectors
Fuel Pressure guage on column plumbed in just before the VP
S&B CAI
Built Auto W/ Mag Hytech pan

So the other day I looked down to see about 1 psi on my fuel pressure gauge, which typically reads 12-16 psi depending on load and filter condition. I shut the truck off, turned the key back on and DID NOT hear the Air Dog whine. So, now that I am about 10 miles from home with an easy drive I decided to go for it. The truck runs fine but I know this is not good for my new VP44. I also noticed that day that the truck DID NOT go into high idle as it usually does in the colder temps when not plugged in.

I have gone through a bunch of wiring and checks and am kinda lost at this point. Ran codes and got P0500 and P1693 from the PCM. I got P0230, P0236 and P1693 from the ECM.

I have checked all the Air Dog wiring. I have a good fuse, with power going to the relay. I do not have power coming out of the relay with the key on. I tried jumping the relay and had no change....the AD will not cycle. I swapped another relay from under the hood and nothing, no cycle. I took the gerator apart and it is clean, moves freely. I put everything back together and changed all the ends that connect to the battery for grins...nothing. I can not get the AD to cycle/prime/work. What would cause the AD to not work and also affect the high idle setting? Any help is apprecaiated.

 

[JR]

You have to briefly bump the starter to activate the signal from the ecm to power up the air dog, and even then you will only see power for a few seconds if the truck is not running. Simply turning the key to the on position won't activate the signal.

 

[whitexc]

Good call JR. You are absolutely correct. I have bumped the starter a few times and still see nothing but I am doing this testing alone so maybe I missed that short signal via the test light. I think this is what I am missing - signal voltage from the ECM. It seems, after a bit more digging on the interwebs, that the computers can go bad in these trucks....but I really want to narrow it down before shelling out that kind of ching.

When I purchased the truck the high idle "mod" was already done. Would this not working and my lack of ECM signal for the AD have anything in common? Thanks again folks.

 

[JR]

To go into high idle the ecm needs to see a specific set of parameters. Intake Manifold Temperature less than 32°F, Coolant Temp is less than 140°F, transmission is in Neutral or Park and the Service Brake pedal is not depressed, throttle = 0% and vehicle Speed = 0 mph. If all parameters are met AND the ecm sees intake manifold temperature below 15°F 3 cylinder high idle will engage. If just one of these parameters are not met the truck will not go into high idle.

As for not getting voltage, I'd disconnect the wiring harness where the AD harness plugs into the engine harness, gently probe the pins with a volt meter and have someone bump the starter. This will tell you if your issue is on the vehicle side or the AD side.

 

[DavidC]

After bumping the starter it should run for 30ish seconds. I had a intermittent problem with mine for a while and installed a bypass switch in the cab that will send power to the pump. That intermittent problem has since gone away for some reason. It is nice having the switch if need be.

Dave

 

[whitexc]

Well, I kind of feel like an ***** but I found my problem. I am quite sure the ground on the computer at the firewall was my issue. It was good and crusty. I overlooked it yesterday when I went through the connections. I went back over everything today and saw that it, cleaned it along with cleaning all battery connections and applying dielectric grease and wala....the pump kicked on. I am still not sure if my high idle works as the temp was warmer today. I will see in the next few days if that is operational.

Next is a rebuild on the vacuum pump (bought the Cummins kit) and maybe a new PS pump as long as I have it apart. I did the Redhead steering gear last year. Any suggestions on where to get a PS pump?

Thanks folks.

 

[whitexc]

High idle works....verified this morning.

KISS - Keep It Simple Stupid! I got way farther into this than necessary but at least things are back to normal.

 

[petersonj]

I got way farther into this than necessary but at least things are back to normal.

Your diligence paid off - you didn't throw parts at it. Good job.

- John

 

[JR]

It never hurts to ask questions! Hopefully you've resolved your issue, I'm not remembering there being a ground on the firewall from The ecm...pcm? Perhaps, but don't remember the ecm being grounded there but my memory has failed me on more than one occasion :-laf I believe the ground for the ecm is on the engine block behind the starter. It's very hard to see with the starter in place.
The trigger signal from the ecm is a known failure point as these trucks age. Some start going out intermittent, some go straight tango.

 

[petersonj]

I think he may have been talking about the PCM on the firewall and there is a ground at that location. I am not sure exactly how it would relate to his fuel problem, but since the ECM and PCM talk to each other, maybe it is related.

- John

 

[Pythonater]

Airdogs are notorious for motors failing. They should warranty it. I had an Airdogs 2, had to buy a spare to keep going until a warrant arrived. Went through 5 of them in a million kilometers.

 

[RDeFayette]

did you read the thread? He found the problem it was bad ground. AD will warranty a bad pump IF the warranty card was sent in. (assuming the pump is bad and it is not a wiring issue as this was).

 

[Pythonater]

did you read the thread? He found the problem it was bad ground. AD will warranty a bad pump IF the warranty card was sent in. (assuming the pump is bad and it is not a wiring issue as this was).

Sorry Bob, just stating my experience. Passing on a possible solution.

 

[RDeFayette]

Sorry Bob, just stating my experience. Passing on a possible solution.

understand that but the solution was the ground. don't apologize

 

[whitexc]

I am on the second AD pump in 6 years. I did send the warranty card in last time so it should be covered next time around.