Engine/Transmission (1998.5 - 2002) Sort of pregnant?/ Lift Pump 'sort of' dead?

[VicR]

I know a girl can't be sort-of pregant, but can a lift pump be 'sort of' dead? Truck is a 99 w/ 43,000 miles on it.



Just put in my westach electric fuel pressure and had the following:



10. 5 at idle

8 at 2000 RPM

5-6 at WOT.



I had the same readings both pre and post fuel filter. Also tried it with and without the brass 45' fitting (figured there might be some air in the system. )



From all the past threads I could find, this seems to be at the low end BUT it also seems that most pumps are either OK with high pressures or DOA with 0 pressures... So I had a few questions:



1. I have heard the acceptable low is 8 PSI, but I wonder how much variation there is in gauges. Could my 5-6 really be 8?



2. Does anyone know where the D/C spec is written? I can just hear my 5-star dealer saying that it's within spec... and the truck runs fine, etc. Its a 100 mile round trip to the only good dealer in No. Nevada, and I hate to waste that if they are just going to say its within spec.



3. So if I just have a weak lift pump, so what? How little fuel before the injection pump has trouble? If my injection pump has been running lean for a while, wouldn't I be better off just letting it die and get a warranty replacement?



4. How hard is a new lift pump? I seem to recall they were only around $150 - if thats the case I might just put a new one in and avoid the hassle. But this might be a bad idea if the injection pump has already suffered (see point 3)



Thanks,



-Vic

 

[VicR]

READ THE INSTRUCTIONS!

Oops. Here in my 99 shop manual, page 14-80, it says that the PSI at the inlet port of the filter should be 10 PSI minimum at idle. I'm at the bottom of the range, but I'm there so I guess all is well.



Interestingly enough, it says the maximum drop across the filter shouldn't exceed more than 5 PSI. Wow - thats quite a drop.



-Vic

 

[speedracer]

get it replaced

When I put in my gauge, my readings were quite similar to yours. Got down to 5psi under load above 2000 rpm. Dealer replaced it no problem. I'd get it changed before it causes damage to the vp44 or leaves you stranded somewhere. Call the dealer first and make sure they have a lift pump in stock and try(if they are a decent dealer) to arrange a one stop repair. As opposed to going in for diagnosis then returning for fix. It only took my dealer an hour or so to replace the pump, so if these guys will work with you, it should be fairly painless. You can also consider using the magic phrase 'hard starting/ low power' to help your odds. Good Luck.

 

[lsenus]

See my post for my troubles with a pump, and the GOOD dealer who took care of me.



https://www.turbodieselregister.com/forums/showthread.php?threadid=49319



Some Catch phrases to remember:

Hard Start/ Low Power.

It happens under any condition.

It starts hard hot or cold.

It doesn't matter if the truck is empty, loaded, or towing.

 

[Big White Beast]

Mine just went too.......

$145 at Cummins for a replacement. Didn't even bother calling the stealer. I need my truck for work and the down time at the dealer would cost me more than a pump.



This time I'm adding a pusher by the tank. Fred Swanson at Desert Diesel parts has a kit for $140 or so and it has all the fittings and connectors included. It's a high volume low pressure pump. That should help the POS lift pump last this time.



Garrett

 

[Big White Beast]

Mine just went too.......

My pressures still read OK but if I trun the key to on it doesn't always pressure up. If I bump the starter it pressures up but loses it before it ends it's cycle. truck starts just fine and I would assume once the VP give it some demand it seems to build pressure like normal. I guess thats just the first step in failing so I'm not taking a chance.



$145 at Cummins for a replacement. Didn't even bother calling the stealer. I need my truck for work and the down time at the dealer would cost me more than a pump.



This time I'm adding a pusher by the tank. Fred Swanson at Desert Diesel parts has a kit for $140 or so and it has all the fittings and connectors included. It's a high volume low pressure pump. That should help the POS lift pump last this time.



Garrett