Engine/Transmission (1998.5 - 2002) fuel pressure gauge

[JMcGarvey]

Well I finally installed my Fuel pressure gauge. Reads 8psi at idle, 5 at 2100 rpms, down to 2 with my foot in it. Called the dealer to see what DC says are recomended fuel pressures. Service manager asked me what I was doing monitoring the or being in the fuel system. Then looked it up and told me that it would cost me 70. 00 to verify that the pressure is low and that I may be eating the lp due to possible warranty void... Truck has 50000 miles on it.

 

[PhilLewis]

Fuel Pressure

About six months ago I had to replace my VP44. At the same time I replaced the lift pump. After recouping the $$$, I installed a westach fuel gauge. Now, I rarely drop below 10 psi @ WOT. I would recommend a new lift pump if yours is oem. If the LP has been replaced, you may consider other problems. I believe the LP is about $150 from cummins. I think that amount is not worth fretting over when the VP44 is $1500+. Don't mess with the dealer, they will only confuse you and waste your money. I'll bet your current readings are fairly accurate.



Phil



Edit: I've been out of warranty for a year now. I forget that some folks have to deal with D/C. They spec fuel psi as 8 psi minimum I believe. Sounds like you'll have to fight for a LP even if they do give it to you. After my experience, I would just put one on myself so they don 't mess your ride up even more. The fuel psi gauge should have been standard equipment considering the problems with the factory set up and in a fair world would not void the warranty.

 

[JMcGarvey]

Thanks for the reply. I would tend to believe that the gauge is fairly accurate. I tapped into the system at the bottom of the fuel filter with a replacement banjo that was taped and also is higher flow. The gauge is a mechanical from Banks with an isolator that has no air in the line after the isolator. I have an appointment in the morning at the dealer... under 100,000 or added care plus warranty.

 

[BillGotthelf]

Don't accept "its normal" from the dealer. At WOT 2lbs of pressure is not enough extra fuel to cool and lube injector pump.

 

[dvaughan]

I have a 2001 with 45,600 miles and if you look in your manual I think it says that the fuel pump is under warranty for 40,000 miles or 36 months, which ever comes first?

 

[d.miner]

I bet Dodge has had their share of folks ask them to test their fuel pressure only to find out it was fine. The $ 70. 00 charge is probably an attempt to recoup their cost if it's "within spec" (sore spot). I've seen others write that they were quoted $ 80. 00.



Some dealers are no longer going by psi and are focused on fuel flow.



Clearly this is the weak link and Dodge has not done a good job of owning up to this weakness and helping with a fix.



It seems silly to play games when it should be handled straight up, I've heard that if you go in acting ignorant to lift pumps but say you have a starting problem or surging problem they check it for you no charge.



Silly... . doctors don't like patients telling them what's wrong and highly trained... ... ... er, mechanics don't like the public telling them how to fix their vehicles.



I wish you well !

 

[Thomas]

This Transfer Pump Diagnosis seems to have been published more recently than any of the factory service manuals covering the Cummins ISB.



Some dealers check pressure. Others check flow.

 

[d.miner]

Well Thomas, that's pretty exhaustive... .



Looks like they have thought it out well and move step by step checking for everything.



Thanks for the link, it was very helpful and explains the pressure vs. flow issue.

 

[JMcGarvey]

Got my truck back from the shop. 54. 00 dollars poorer. My mechanical gauge is accurate. Shop verified that, no new lp though. Claim that the volume could be enough... did pressure check and would not do the volume test...