Very simple wiring the new in tank LP. They use a relay, Grab power from the positive terminal of the battery for one end of the contacts. Connect the other to the intank LP. They use the old LP wiring harness to trigger the relay which makes contact with the battery connection and in tank LP. Hope this helps.

 

Yup, simple enough, but some mechanics like I stated earlier are behind the curve.

Just trying to get the message out that don't always blame the product. Sometimes There's more to things than what appears to be.

 

They make clamps for this that are a little cheaper than vise grips. Same principal though. Also, my 2005 d-max had an in-tank pump. You could hear it every time you started it.

 

I too had my LP replaced at 22,000 miles with the in tank replacement, and I now have 33,000 miles on the truck, and its been extremely reliable. I would suspect another problem with your fuel delivery that is causing this failure. I will say that if my current in tank pump goes, I will get an aftermarket pump, like walbro or the like.
Scott

 

Well for what it's worth my truck is running again. The dealer called and said they removed the relay, unplugged the ECM, and powered up the pump manually and it worked the first time. They plugged the stuff all back in and I've been driving it ever since with no percieved difference in performance than before. I'm going through all the wiring this weekend. I also have a fuel pressure gauge on the way and I will be yanking the tank to see if a walbro will fit in the tank instead of the stocker. I might put another pickup on just in case I decide to go with an external (hate that idea though).

Andy

 

Walbro makes in tank pumps. They make alot of them. Do a search on google or something and you'll see that most oem pumps are Walbro. And I really wish you could explain to me why you like the in tank version instead of an external pump. Enquiring minds want to know...

 

I realize they make in-tank pumps but there is chance that in-tank pump could just bolt in so I will check it out. Why do I prefer the in-tank? Because it never loses prime and losing prime kills pumps. I have a lot of experience with various external pumps on my EFI projects and that's what I've learned.

Andy

 

Today I put an autometer electric fuel pressure gauge in and it was interesting to watch. At idle I have about 10 lbs of pressure. Driving around it goes down to 7 or so (interstate, 75mph). I can pull it down to ~1 or 2lbs if I really try hard.

The really interesting part is that the needle was twitching a LOT while driving. I was twitching the whole time, really annoying. On the last leg of my test drive tonight I went over rumble strips coming up to a stop sign and the twitching stopped. I mean stopped 100%, then it was only nice smooth transitions.

Is the twitching anything to do with the sender being mounted on the CP3? Could it be because the fuel level in the tank is so low (I have kept it low so I can drop the tank this weekend)?

Andy

 

I don't think it's a good idea to mount the sender directly to the cp3. Too much vibration will kill it in short order. Matter of fact, Autometer advised against using their sender with our Cummins. Anyway, I used a 12-14" piece of rubber fuel line to extend the sender up and away from the cp3 inlet. So far, I've been good for about 15k miles like this (knocking on wood). Now as far as twitching... my needle does this slightly all the time. Probably the fact that the sender is very sensitive and the cp3 is pulsing causing variations in pressure. Just my opinion, not a fact....

 

I saw that little note there about not being for use on a Cummins. I assume it meant that it's not meant for use as a rail pressure sensor. Have there actually been failures with it on the CP3?

Andy

 

It would never be used as a rail pressure sensor. Do you understand the pressures that the common rail reaches?
I've read of failures due to the sender from the cp3 but haven't seen any firsthand. Just use a piece of fuel line to insulate the cp3 and the sender and you should be fine.

 

I know it can't be used for that, I was just trying to figure out the warning from Autometer. It's such a nice clean install when it's mounted to the CP3 like it is now. It's a pity to have to ziptie it up to something else. Arg!

Andy

 

Didn't mean to sound condesending.. sorry.

Yes it does kinda look funky, but if it helps it live, it's a must do... Plus mine is mounted to a "tee" fitting with a loop going back to the return on the cp3. This is to keep the pressure of the Walbro down at an acceptable range.

 

Trik is right about the Autometer warning. It's due mainly to vibration from the Cummins killing the senders. I also used a 30" rubber hose from Geno's to isolate my sender from the engine. In addition, I put a snubber right before the hose to keep any pressure spikes from harming the sender. I don't have any of the twitching that you guys describe, but my gauge will still react instantly to throttle changes.

 

Hey Blast, do you think it's the snubber that's stopping the twitching. When I mean twitch, I mean the needle may vary by 1/2lb here and there when at idle. Nothing radical. Responds instantly to throttle as you described. Twitch is hard to notice unless your staring at the guage, which means you aren't watching the road...