quazilla rail/fuel pressure guage problem?

[231jasonS]

Has anyone figured out how to keep a fuel pressure sending unit from vibrating to death on the CP3? I have had two different sending units from Quad go bad. Last time i replaced it i was told there was a better sending unit, but dont know where to get.



Can anyone help? Is there a better mounting location for the sender unit then the inlet for the CP3..... i dont wan to buy a new guage, just want to make the exsisting quad guage work correctly.



Sugestions?

 

[duraman03]

What is your gauge doing? I am having a problem with mine. The pressure is reading all over the place.

 

[231jasonS]

it jumps all over goes from 0 pst to 8 then will show 13-15 and drop to 0 again... ... . it was doing same thing last time i replaced the sending unit and it has worked well for past 6-9 mons.



Roark @ quadzilla sent me a new sender and said the vibrations were the caus of the short life span. He was supposed to be working on a better sending unit at the time but i dont know what happened.

 

[grabinov]

I had the same problem with my quad fuel pressure sender. I got the same answer about the sending unit being upgraded to a newer model - described not as more accurate, but more sensitive in the pressure ranges that our trucks generally run - say 0 to 30 pounds.

Has anyone had any problems with the rail pressure gauge? I installed my rail/fuel pressure setup a while ago, and a week later the truck stalled on me twice within a mile of my house and then died pulling in the driveway (try that on a downhill driveway - exciting - Almost parked in the living room). I was able to get it started after about ten tries over a two day period.

I took it in to the dealer and it had a stack of codes. They cleared them and couldn't find anything wrong. I took off the fuel side of the system (still running the regular Commander) and haven't had a problem since.

I can't say for sure that the Quad fuel pressure or rail pressure senders had anything to do with the problem, just that one shortly preceded the other and I haven't had the problem since removing the senders.

I have since switched to a FASS pump and am considering giving the Quad senders a try again, with the fuel pressure sender attached to the fuel line and nowhere near my high pressure pump!

 

[MA2LA]

what about relocating the sending unit closer to the filter housing that might help. Or set up a fuel line to relocated it over to the boy to get it away from the vibration of the motor as much aspossible.

 

[231jasonS]

The rail pressure plug was probally th eproblem with tthe truck sputtering and running bad. If the RP plug is loose or doesnt have a good connection it will make the truck feel like its running on 2-3 clys and die. I replaced mine and used a bunch of dielectrical grease and zip ties in the connector.



I think the problem is in the design. The quad plug is soft plastic and flex's, you can squeeze the connector and it will stumble. Its been fine since i ziptied it and filled it with the grease.



Maybe i can move the sender to the oem fuel filter housing. Ill have to look further into it.

 

[moonranch]

Maybe i can move the sender to the oem fuel filter housing. Ill have to look further into it.

I currently have the sending unit mounted to the top of the fuel filter, and the gauge is still jumpy. I don't think that will fix the problem.

 

[RDyson]

The best thing you can do for the vibration is to relocate the pressure sensor somewhere other than on the engine. Use a length of braided s/s hose or some use a grease gun hose to mount the sensor on the firewall or fender. I'm using the s/s braided hose that I got from Diesel Manor when I got my gauges. I have not had any problems with my set-up.



Randy

 

[LowFly]

OR... . i would suggest this.....



Auto Meter

 

[231jasonS]

OR... . i would suggest this.....



Auto Meter

Would this work with an electronic sending unit?



I called quad yesterday and they have a "severe duty" sneding unit. ill try that and see if it works any better/longer.



The banjo bolt replacement fitting quad supplied to go ontop of the CP3 should work on the OEM fuel filter housing, right? Are they the same size fitting?

 

[LowFly]

Would this work with an electronic sending unit?



I called quad yesterday and they have a "severe duty" sneding unit. ill try that and see if it works any better/longer.



The banjo bolt replacement fitting quad supplied to go ontop of the CP3 should work on the OEM fuel filter housing, right? Are they the same size fitting?

Yes sir... its a 1/8" NPT male to 1/8" NPT female. Its to protect the sensitive contact in any electrical sending unit. I would not run an electric gauge without one of these. More or less its a shock absorber.

 

[231jasonS]

Well I installed a new and improved sending unit from Quad today, so far so good. Ill have to wait and see if it lasts.

 

[231jasonS]

Well it did not last... ... I got another sender and a Isspro snubber unit. Still wont stay in one place jumps from 13-14 down to zero all the time.

Anyone else have another fix for this?

 

[moonranch]

Jason,
I have not tried it, but I noticed on Quadzilla's website that they are now offering an "upgraded" fuel pressure sending unit. It looks like you need to send in your Commander and $, and they modify it for the different sending unit. I just got a "warranty" replacement original sending unit(after a 6 month wait), I will re-install it and see if it works any better.

 

[231jasonS]

I think that is the same one ive replaced twice. Unless they have a new, "new" one.

 

[moonranch]

Did you send your Commander in to get it reconfigured for the new sending unit? They just sent me a replacement sending unit that was identicle to the original.

 

[231jasonS]

I only have the fuel/rail gauge... no commander. When i got the "new sender it was the same as the old. So i suspect hey dont have a newer version of the sending unit.

 

[MA2LA]

I relocated my sending unit when I did my airdog and it went right on the airdog unit and I haven't had any problems since i did it.

 

[231jasonS]

Maybe ill consider this option. I hate to re route everything but what is a guy to do?

MA2LA- any pics?