Gentlemen,

Well, I believe that my lift pump is on the way out. Please give me some input on what you think about these symptoms and see if you all agree that it about to bite the dirt.

Fires up just fine. Reads 15+ psi for about two or three miles at slow speed and then drops to 5 psi. On acceleration it drops to 0 psi. When I let off the pedal, it increases to 5 psi again.

Now, if I pull over and let it idle, it stays at 5 to 7 PSI. If I turn the engine off and re-start it, it immediately goes to 15+ psi and will stay there and not vary too much. On hard acceleration, it drops to 9-10 psi.

The next time I drive it, it may or may not repeat the same scenario. The problem is that it has done this when I checked it with my portable gauge and now the same with the permanent Westach. I am pretty sure it is not the Westach or Hopper gauges.

Have any of you had a lift pump act like this that did not finally go out?

My truck has 9,721 miles on it and it is an 02. The dealer will do a flow test and replace the lp if they can duplicate the problem while it is there. Of course, I don't want to take it if I can avoid it.

Thanks for your opinions.

Tom

 

i just put gauges in and noticed the SAME EXACT problem. i am putting my new lift pump in tomorrow so i will let you know if it cures it!!! anyone else's input is appreciated by me too.

 

Lift pump pressure should never go to 0. You need to park your truck and get a new one before you kill your injector pump.

 

I had the same problem. I decided to clean the contacts wit elect contact cleaner at the lift pump and use dielectric grease and reinstall. 15 at idle, 13 at 75mph,9 at WOT. You might try this first and save a buck or two.

 

Lol mine never went to zero in went to -.5 to -1 LoL.

 

just got my new pump in. this did cure the problem. i am at 15 psi at idle all the time and about 10-11 psi at wot. hopefully this one will last a little longer than the last.

 

Thanks for your input on my lift pump question. I can see the symptoms I described are not that unusual.

I'm just waiting for Monday morning to come so I can take it to the dealer. The service manager said if I have it there by 6:15 a.m. they can have it ready in the evening. Busy place I guess considering it should take about 30 minutes to change.

I wonder how many times this will happen while its still in warranty? This seems a little quick for a lift pump to go out on a totally stock engine.

Thanks again,

Tom

 

You think that's quick,
I lost my injection pump, yes, the $1300 one, with only 4,000 miles on the ole odometer.

Lift pump was, and still is, just fine, 33,000 miles later.

I think the going rate is one lift pump every 33K miles or so.
I'm about due.


phox

 

FASS. Never buy another lp.

 

I have had mine jump around but it was the fp guage not the pump. scared me so I turned off the truck and it sat at 5 psi. I bleed the line between the isolater and the cab a little and it fixed the problem. I didn't figure it was the pump since I had only had it in for 2 weeks when this happened.

 

Mine is doing exactly the same thing. I tried the dielectric grease trick to no avail. My new lift pump will be here Thursday. This is 2 lift pump failures in 25k miles.

 

Sixpack and others,

The new lift pump was installed today and so far so good. But, right out of the box the new lp runs a pound below the old one, when it was operating right. Makes me wonder about the Carter pumps.

Believe it or not, the old one passed the flow test even with it only putting out 5 psi at idle. I wonder about that also but the service department replaced it because they could see that it was malfunctioning, when it would drop from 15 psi to 5 psi.

I hope this one makes it a little longer. At least, I saved the injection pump.

According to the service manager, the 2004 and 2005 have the lift pumps located at the rear of the truck near the fuel tank.

Tom