i am having problems w/ my autometer 30psi fuell pressure gauge after installing it. i have an airdog150 and currently am NOT using my smarty so at the moment i have stock programing.

sometimes i drive the truck and the gauge reads 13-14psi at idle and 11psi wot. then other times i drive the truck it will show 18-19psi at idle and 16psi at wot. one time i started the truck and the gauge showed 18psi and i tapped the throttle then it dropped and held at 13-14psi. im also having a problem making boost as well. i can barely get it to make 20psi but i believe it is because it is so cold here these last few days. it seems to always have trouble making boost when its below 40 degrees outside.

i spoke w/ an autometer tech and he told me i need to use a pressure restricter to run this gauge on a cummins. he said sometimes cummins motors somehow cause a pressure spike that can damage the gauge. i told him i thought the sensor or gauge was bad, but they insisted i try this restricter (snubber) before they will warranty anything. the restricter cost me another $22.

i told him i have an aftermarket fuel system but he still insisted on this part. anyone else know anything about this?

 

Sounds like bs to me But what do I know lol Some techies on here might be able to help out more. Plus I have a second gen and I run an electric oil pressure guage for my fuel guage (third of the price and safer than people who run a mech in there cab)

But I do have to say that afer I put mine together it was doing what your's is doing found out that I had a connector that was leaking air in the line and causing a pressure drop. Look at the pump and see if the connector between the pump and tank is wet that could be the one, might want to wrench it to be sure.

Just a thought hope it helps.

 

I had an autometer electric fuel pressure gauge go bad.Started off like your describing then just wouldn't read at all on certain days.Sent it back and got a new one and had no problems with it.Never ran this snubber and was running a Fass 150 the whole time.

 

havent heard of the restrictor he's talking about. I have an aftermarket fuel system, and it spikes sometimes. as long as your over 10 psi on the gauge with your foot in it, I wouldnt worry about it too much, you dont want to dry out the CP3

 

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Ghost Ram:

FWIW, I had the exact same "Autometer" Gauge as you and mine did the EXACT same thing and Autometer told me the same thing also. As it turned out, I installed the pressure restrictor and on my truck it DID NOTHING to help! Turned out that the sending unit was going bad, so I replaced it at the cost of $100.00 and in about three months the new sending unit went bad too! Anyway, I took it out and went with a "DiPricol Mechanical F.P. Gauge" and so far, so good!

Good luck to you with that Autometer Gauge.

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John_P

 

I've installed quite a few Autometers with the electronic senders. Have not had one problem. Where are you installing the sender exactly? I know the sender is highly sensative and vibration from the Cummins in general and the CP3 in specific can wreak havoc. You should use a good length of hose to feed the sender and isolate it from these vibrations.

 

Like Trik said, I've never had bad luck with Autometer gauges. Here's how I mounted mine. The thing you should take away from the picture is the rubber line to isolate the sending unit. The sending unit will die a quick death if it is plumber right to any hard part.

 

Good pics. Mine was similar when I was reading right at the CP3 but the line was about 18" long.

Not to hijack, but what's that controller/screen thing to the right of your steering wheel?

 

That's my super secret........................cheapo XM receiver. Almost had ya.

 

my sending unit is mounted on the cp3 w/ a tapped 90* fuel line fitting. im sure it is going bad already so once i recieve the snubber and it doesnt work then i will give autometer a call back and ask for a new gauge and sender. i will mount the new one in the fuel line somewhere away from the motor.

if i continue having problems in the future i will get rid of the fuel gauge all together.

thanks for everyones help, it has explained what is causing my problem. what about the low boost, does anyone have trouble making boost when its very cold out? i guess its possible i could have gotten a leak in my boost gauge line when i re-installed my gauges into the new pod w/ the fuel gauge. if i still have the boost problem when it warms up on monday then i will check for leaks.

 

I've never had any problems building boost down to -33 F which is as cold as I've had this truck.

 

Quick note....if you have a leader line, be sure to bleed out any air that gets trapped in when you install it. I would get your sealant on the fitting and just start the first couple of threads (Even better if you use AN fittings)…then run the lift pump and quickly tighten the sending unit up. Might put a few rags under. I have had a few instances that this caused WOT pressure drops but good pressure under idle.

 

Good point, I have a swivel at the end of my AN fitting and bled it right to the sensor.

 

when i bought my pressure snubber from autometer. they had two types-brass and stainless steel. the stainless steel one cost me 10.00 from them. you can also get them mcmaster-carr.

 

well i removed the sender from the cp3 and installed an under the hood mechanical gauge in its place to check pressure and this thing is jumping around like crazy between 5-15psi. im guessing its because of all the vibration from the engine.

so im sure i will install a new sender somewhere else in the fuel line away from the engine. but it looks like the pressure will end up being around 13psi and i thought this was low for the airdog150???