HI, MY TRUCK JUST STARTED TAKING LONGER TO START, I HAPPENS EVERY 1 OUT OF 3 TIMES I START HER UP. JUST REPLACED AIRDOG FILTER AND SEPARATOR, AIRFILTER, PURGED SYSTEM AND IS STILL DOING THE SAME. HAVE ABOUT 40K ON A NEW VP44 AND NEVER HAD ANY PROBLEMS. FUEL PRESSURE READING IS 17PSI AT IDLE AND 15PSI AT WOT. IF FEELS LIKE ITS GETTING AIR IN THE SYSTEM, IT TAKES ABOUT 5-10 SECONDS TO START AND WHEN IT DOES IT AUTO-ACCELERATES. ANY BODY FAMILIAR WITH THESE ISSUES???

Error codes?

IT AUTO-ACCELERATES

When you say auto-accelerates do you mean all the way to red-line like someone mashed the throttle to the floor or is a jerky kind of up and down revving? I've got a hunch it might be a ECM problem but need more info. on it...

Sounds like you have good fuel pressure. Try reading this link especially under long crank times. Perhaps it may be of help. http://www.bluechipdiesel.com/vp44_diagnostics.html

specs on the truck...?

Good Morning, first i'd like to apologize for not responding earlier to my tread due to computer problems. My truck is still doing the same and have noticed it now takes longer for the airdog pump to go on after turning the key, it will only start when the pump goes on. I have tried replacing the relay at the airdog harness, i tried bypassing the relay at the harness and the pump goes on quickly. I also did a test at the connection that comes from the ecm and gives power to the airdog harness, i unplugged it and used a test light while someone turned the key and the tester will not go on until 5 or 10 seconds, contrary to this the pump goes on when i crank the key. Could these be a problem with the ecm or is there another relay that needs to be checked. Thanks..

2000 ram 3500, nv4500 transmission, 4x4, 144k, silverline 4" stainless steel turbo back exhaust with dual stacks, ats intake horn, triple isspro ev2 gages, airdog II 165, new vp44, no programmers.

Electrically the pump doesn't go through the ECM( If that is what was implied or additional cause and effect). It's a seperate add on. I would rule it out unless it was run through a factory system harness. It should be independent of any other wiring. It does have a relay or two. On my pump it runs on ignition and start at a constant. My neighbor has a pump only system and I believe it runs on demand @ pressure only. It may be a raptor. It wouldn't hurt to check the 12 volt source. I wired mine through the fuse panel. You can always contact Airdog too.Another thing to check would be the fuel shut off solenoid and relay. It has to pull all the way in to start. Use a mirror or have someone crank it for you. Good luck.

Good Morning, first i'd like to apologize for not responding earlier to my tread due to computer problems. My truck is still doing the same and have noticed it now takes longer for the airdog pump to go on after turning the key, it will only start when the pump goes on. I have tried replacing the relay at the airdog harness, i tried bypassing the relay at the harness and the pump goes on quickly. I also did a test at the connection that comes from the ecm and gives power to the airdog harness, i unplugged it and used a test light while someone turned the key and the tester will not go on until 5 or 10 seconds, contrary to this the pump goes on when i crank the key. Could these be a problem with the ecm or is there another relay that needs to be checked. Thanks..

2000 ram 3500, nv4500 transmission, 4x4, 144k, silverline 4" stainless steel turbo back exhaust with dual stacks, ats intake horn, triple isspro ev2 gages, airdog II 165, new vp44, no programmers.

Just curious.. When your cranking, and you realize its not going to start right up, can you let up crank again and it fires immediately. My Son`s 99 does this all the time at operating temperature.

His acts like the pressure is bleeding off inside the VP, and letting up, and recranking seems to reset something.

Does the wait to start light come on right away or does it delay to light up?

does the wait to start light come on right away or does it delay to light up?

the wait to start light goes on right away every time.

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Just curious.. When your cranking, and you realize its not going to start right up, can you let up crank again and it fires immediately. My Son`s 99 does this all the time at operating temperature.

His acts like the pressure is bleeding off inside the VP, and letting up, and recranking seems to reset something.

It only starts after the pump goes on, sometimes it goes on rigth away, sometimes it goes on after the bell, if not then i give her a quick crank to wake up the pump. If i turn the key and the pump doesnt go on and i keep cranking it will start after 5 or 10 seconds of cranking.

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Electrically the pump doesn't go through the ECM( If that is what was implied or additional cause and effect). It's a seperate add on. I would rule it out unless it was run through a factory system harness. It should be independent of any other wiring. It does have a relay or two. On my pump it runs on ignition and start at a constant. My neighbor has a pump only system and I believe it runs on demand @ pressure only. It may be a raptor. It wouldn't hurt to check the 12 volt source. I wired mine through the fuse panel.

You can always contact Airdog too.

Another thing to check would be the fuel shut off solenoid and relay. It has to pull all the way in to start. Use a mirror or have someone crank it for you. Good luck.

The airdog harness does hook up to a factory harness, then gets power directly from the battery.

I would get a test light out and see if the yellow/white wire is getting power when the engine is running. While starting it should flicker/flash.

I would get a test light out and see if the yellow/white wire is getting power when the engine is running. While starting it should flicker/flash.

just checked the yellow/white wires #15 & #35 and they both light up when the engine is running, it does not when cranking.  when I crank the engine without waiting for the airdog to go on theres no power on the wires, after the airgod goes on, theres power, this is with the engine off and the key on start. 

Electrically the pump doesn't go through the ECM( If that is what was implied or additional cause and effect). It's a seperate add on. I would rule it out unless it was run through a factory system harness. It should be independent of any other wiring. It does have a relay or two. On my pump it runs on ignition and start at a constant. My neighbor has a pump only system and I believe it runs on demand @ pressure only. It may be a raptor. It wouldn't hurt to check the 12 volt source. I wired mine through the fuse panel. You can always contact Airdog too.Another thing to check would be the fuel shut off solenoid and relay. It has to pull all the way in to start. Use a mirror or have someone crank it for you. Good luck.

where is the fuel shut off solenoid and relay located?

Your VP truck does not have a fuel shut off solenoid. The 12 valve truck do. Earlier you stated the truck would auto accelerate. Does it go to red line or just rev up and down on its own?

Electrically the pump doesn't go through the ECM( If that is what was implied or additional cause and effect). It's a seperate add on. I would rule it out unless it was run through a factory system harness. It should be independent of any other wiring. It does have a relay or two. On my pump it runs on ignition and start at a constant. My neighbor has a pump only system and I believe it runs on demand @ pressure only. It may be a raptor. It wouldn't hurt to check the 12 volt source. I wired mine through the fuse panel. You can always contact Airdog too.Another thing to check would be the fuel shut off solenoid and relay. It has to pull all the way in to start. Use a mirror or have someone crank it for you. Good luck.

Even though the pump doesnt get its power from directly from the ECM, the ECM is still what switches the relay to run the pump. The pump still needs the ECM to run.