Thread pitch for fuel high pressure line to the Fuel Pressure Regulator
 

I'm trying to connect a fuel pressure gauge on the high-pressure line that connects to the Fuel Pressure Regulator. I need to troubleshoot and want to know what size fittings I need to use my gauge. I was wondering if anyone here knows.

Thanks!!

what are you troubleshooting? chances are we already have the answers.

The very common no-start condition :D.

I've gone through many of the basics, but some things confuse me. For example, I do not see the Check Engine Light (CEL) at any point with the key in ON or RUN, which means there shouldn't be power to the ECU and/or the crank sensor is failing. However, if I put starting fluid in the intake, the car will start! I need to do a little bit more reading here, but today I will probably check the ebox in the engine bay and verify for moisture, and check fuses and modules there. Oh, and the battery is a brand new, proper size (huge!) OEM Audi battery.

The fact the car started with starting fluid made me switch to checking the fuel system. I've checked the fuel pump fuse, the fuel pump relay, and I'm getting a constant stream of fuel to the fuel rail. But since the car is not starting, I'm unsure if I'm getting enough pressure. That's why I'd like to put a gauge in the fuel rail. I've been doing a lot of reading, and I'm also going to add about 5 gallons of petrol :ROFL:. Just in case I'm seeing that problem with the fuel pump basket not sealing.

M14x1.5

If you have less than half a tank put in more than half a tank and let us know if it starts, it may need a few cranks

MikkiJayne...thanks! Very helpful, as always.

Ronin...will do. PS...now I gotta make time to watch the movie this weekend since it's a long holiday weekend here Stateside.