Hey all, I've tried everything I can think of and I can't resolve this issue.  My 2000 automatic won't start because the lift pump (raptor 150) won't turn on.  I had only 3000 miles on it before it suddenly stopped working.  So I checked my ASD relay and my fuel system relay, both were fine.  So I unplugged the pump and bumped the starter and checked voltage with my multimeter.  Got a healthy 12.3-12.7 volts.

 

So I figued the pump was bad and got a new one under warranty.  When the new one came in, the same issue continued.  I figured maybe there was some glitch and the ECM was telling the motor to defuel because the check engine light with p1693 came on when it stopped wanting to start.  I suspect 1689 because I used to get that once in a while during hard starts.

 

So I unplugged my battery terminals and let everything reset.  Plugged everything back in, issue is still there.

 

So what's up?  Should I just hard wire the pump in to the battery?  Is there another relay that could be bad?  How do I go about testing the ground for the pump?

 

Oddly, the truck started without the pump plugged in and ran long enough for me to limp it 2 miles home, but turning it on and then plugging in the pump caused it to die immediately.

can you just put a straight from the battery 12v.  or  as you did and take an amp reading off the pump. I have the older  air dog been fine for some 6 years now

Edited September 19, 201410 yr by Ed ke6bnl

can you just put a straight from the battery 12v.  or  as you did and take an amp reading off the pump. I have the older  air dog been fine for some 6 years now

I took the reading from the wire harness thing that plugs into the pump without the pump connected.

Are you using the ground on the raptor plug or a body ground

Stock lift pump ground is behind the starter bolted to the block. The Raptor ground can be tied to the battery but I typically use a body ground instead.

I had a similar problem. Truck would start fine, run and then quit for no reason. I went thru all of the wiring. Wired to the old pump connections. Got a replacement warranty pump. Before I put the new one on, I wired the pump directly to the battery. Problem fixed! New pump still under the back seat! I was thinking that there was a problem with the ECM. Have not had a problem since the direct wire to the battery.

I had a similar problem. Truck would start fine, run and then quit for no reason. I went thru all of the wiring. Wired to the old pump connections. Got a replacement warranty pump. Before I put the new one on, I wired the pump directly to the battery. Problem fixed! New pump still under the back seat! I was thinking that there was a problem with the ECM. Have not had a problem since the direct wire to the battery.

This is interesting.

Are you saying that you are now wired to the battery with a relay that is activated by the old pump connection from the ECM?

Or is the pump wired directly off the battery with a manual switch to activate the pump?

Edited September 19, 201410 yr by JAG1

Stock lift pump ground is behind the starter bolted to the block. The Raptor ground can be tied to the battery but I typically use a body ground instead.

I should of said when he is testing for power is he using the ground at the plug or a body ground. Just to verify the raptor ground is good

I would just put the raptor on its own relay triggered harness that is signaled by the original pump harness. Takes the load off the ECM and stock harness in case of any issues. As for testing the pump ground, I would just ohm test between the pump and a good ground somewhere. That should tell you if there is any resistance between the pump and ground on the truck.

Raptors use their own relay triggered by the ecm through the stock lift pump plug

Ok. I wasn't sure because when I got my raptor I just got the pump. No harness, nothing but the pump itself. I built the harness and fuel line system on mine.

All raptors/airdogs come with their own harness

Or is the pump wired directly off the battery with a manual switch to activate the pump?

 

I wired directly to the battery with a switch. I am going to change it though. Can't remember who on the forum says to get power from the wiper fuse but that is what I am changing too. Due to some times forgetting to either turn the pump on or off.

 

Wiring to the wipers will get you the momentary no pressure to the pump at start up.

Correct. Trigger wire for relay should go to wiper fuse

All raptors/airdogs come with their own harness

I don't remember who I purchased it from, maybe thouroghbred Diesel, but I was able to purchase just the raptor pump by itself. All is had was the little 6in pigtail sticking out of it. No other harnesses or anything. I will try to figure out where I got it from.

You probably got the universal pump

Thank you all so much for the replies! But I gotta be honest, this is a bit technical for me. I'm pretty solid with mechanical stuff, but electrical has always been a challenge for me.

Anyone want to explain what I should do like you're explaining to someone who only knows the basics of electrical?

If I'm reading this right, I should ground the pump's neutral to the body and leave the hot side as it is through the stock harness with the stock relays in line, right?

Wiring it into the wiper circuit seems a bit beyond my knowledge, unless it's really easy.

And if, after grounding to block or body, the pump still won't turn on, I should just buy a switch from the electrical supply store and run directly from battery? That seems less than ideal but if it is what I have to do to avoid any more down time , I'll do it.

I am thinking of installing a couple buss bars for cleaner wiring under the hood. I've got a few wires going to battery cables and its a pain. My raptor came with a pretty split loom covered harness and relay. Problem is that it's about 6' too long and coiled up and tie wrapped under the hood. Going to shorten and run negative and positive 8 gauge wires to buss bars and shorten up alarm, raptor wires etcetera. Nothing going to battery. Run the 8 gauge wires from the power distribution box lugs. I hate scabbed in wires.

Update: grounded it to body and that didn't fix anything. So either a brand new bad pump or an issue on the hot side. Is the starter relay a potential problem here? The truck wants to turn over and did with the fuel pump unplugged so I doubt that.

I apologize for bumping this again but grounding it did nothing but simply hooking it up to the battery did nothing. So I can't really isolate hot or neutral side as the problem. Guess I'll just wire it into the battery with a switch although that's less than ideal.

You probably got the universal pump

Yep. I found it. Still a pureflow raptor 100 but it is the universal pump. Here.