when idling or driving or wot it moves between 20-22. every now and then it will spike up to 28-30 and back down to 20-22 again. is this bad? could it cause problems? or is this an indication of something bad to come?? thanks guys te airdog 150 and isspro ev2 fuel gauge were ontruck when i bought it. i didnt install it so i do not know much about it Sent from my iPhone using Tapatalk

Is your gauge electronic?

yep its electronic

Most likely the sender is going out. I have an electronic sender in mine but i dont trust it so i bought a cheap oil pressure gauge off of amazon just to make sure. Also have a quick connect fitting to check it with another gauge if either acts up. Im really paranoid about fuel pressure. My airdog runs around 20psi and will bogg down to 13 when the intake heaters kick in. I also have a snubber and a grease gun hose to protect from hammering and vibrations

Water hammer killed the sender. Really common for electric gauges to fail within about 1-2 years without water hammer protection.

so does the gauge need replaced? is that what your talking about when you say the "sender"or is it a piece inside the gauge? i cant seem to find just a gauge, its all wiring and all the other stuff i already have

Here is what the sender should look like, it will be on the injection pump. http://www.dieselmanor.com/isspro/r89141.asp Here is the oil pressure gauge I got http://www.amazon.com/gp/product/B000FJS4PO/ref=oh_details_o00_s00_i01?ie=UTF8&psc=1 And here is the copper tubing kit I got because I didn't trust the plastic tubing even though they say it will work with diesel http://www.amazon.com/gp/product/B00029JYF6/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1

im a little confused on what the oil pressure gauge and copper tubing has to do with things. im here to be educated so school me! would it be wiser just to use a mechanical fp gauge instead? Sent from my iPhone using Tapatalk

Oil pressure and fuel pressure are the same thing. Thats why i just used an oil pressure gauge. The copper tubing is just another fail safe over the plastic tubing since i am running fuel into the cab. I went with a mechanical gauge that way I always know pressure even if the electronic gauge goes out.

I'm using a mechanical gauge but just plumbed directly to the gauge with air brake line.

Exactly what all the big over the truck use for plumbing for air, oil pressure and other gauges. Soft copper tubing is known for flex failures so that why I typically warn against copper tubing usage. Most people get carried away and use steel braided lines which is total over kill and typically very difficult to route in the dash. Where air brake line is oil and fuel ready and with a needle valve if the line should leak it will not spray but merely drip and a fast pace. If a line was to fail and start to leak trust me you'll smell it for sure. At that point just shut the needle valve and continue till your travels till you home where you can fix it.

My past history with old school nylon tubing it will work but the nylon gets brittle under the hood and typically gets broke while working on the engine. I normally broke mine are at the compression fitting. After getting tried of that I found air brake line and never had a single problem after that.

Even with air brake tubing I would double check that it can be used with the diesel. I used to sell air brake tubing made by tectran and they specifically stated that it is not to be used with fuels or oil. Just as a precaution.

are the mechanical ones easy to hook up? i may just go that route if i can find one to match the ones i have right now Sent from my iPhone using Tapatalk

Pretty simple. Tap the fuel line somewhere of your choice after your last filter. Install a needle valve to protect the gauge and run a line from it to the gauge. The only power you need is for the light. I also installed a big line kit from the oe canister to the VP at the same time, tapped that line for my gauge. I am going to swap out to the polyon tubing Mike is using on day in the futurel

thank you guys a lot!know of any factory matching mechanical fuel pressure gauges?