Topic: Rich Problems continue

[Red93YJ]

Ok, I tested the fuel pressure on the injector rail first thing this morning. It read 95 psi (no that's not a typo). So first thing first, I replaced the fuel pressure regulator. Fired it up again, still 95 psi.

So, next thing must be a clogged return line. So, I unhook the return line from the rail and from the tank and blow air through the line. Nothing really came out that would have been obstructing the fuel flow through the line. Hooked everything back up, fired it up again, and still had the extremely high fuel pressure. So we unhook the line by the tank, leaving it hooked up at the rail, and the engines runs like a top. Thus meaning that the clog must be from the hard line outside of the tank, through the return fitting on the fuel pump.

I get the air down there, blow air through that part of the line until you we could hear/feel the air coming out of the filler hole (cap removed). Put it all back together, fired it up, and back at 95 psi fuel pressure. I unhook the line in front of the tank, and aim it into a bucket to catch the returned fuel, fire it up, and it runs perfectly at 40 psi.

So, my assumption of course it that the clog is in the return part of the fuel pump and that i'm going to have to drop the tank again and replace the fuel pump.

Is there anything that I'm missing, or does it seem like i'm on the right track?

Thanks

[Jeffy]

Ok, I tested the fuel pressure on the injector rail first thing this morning. It read 95 psi (no that's not a typo). So first thing first, I replaced the fuel pressure regulator. Fired it up again, still 95 psi.

So, next thing must be a clogged return line. So, I unhook the return line from the rail and from the tank and blow air through the line. Nothing really came out that would have been obstructing the fuel flow through the line. Hooked everything back up, fired it up again, and still had the extremely high fuel pressure. So we unhook the line by the tank, leaving it hooked up at the rail, and the engines runs like a top. Thus meaning that the clog must be from the hard line outside of the tank, through the return fitting on the fuel pump.

I get the air down there, blow air through that part of the line until you we could hear/feel the air coming out of the filler hole (cap removed). Put it all back together, fired it up, and back at 95 psi fuel pressure. I unhook the line in front of the tank, and aim it into a bucket to catch the returned fuel, fire it up, and it runs perfectly at 40 psi.

So, my assumption of course it that the clog is in the return part of the fuel pump and that i'm going to have to drop the tank again and replace the fuel pump.

Is there anything that I'm missing, or does it seem like i'm on the right track?

Thanks

Wow, what a PITA.  I think you're on track though. Nice detective work.

[Red93YJ]

yeah, i'm a soon to be expert in dropping the gas tank.

Hopefully this will fix things though. 9 mpg is pretty tough to handle out of a 4 banger...lol

[Red93YJ]

ok, actually ended up being that my body mounts had deteriorated and the body had lowered down onto the fuel lines where they cross over the frame and under the body, thus pinching off the return line.

I replaced the damaged lines, installed a temporary fix to the deteriorated body mount bushings, and everything is better than ever. Fuel pressure checks out great, no more trouble code, no rich exhaust smell, no backfiring, etc...i'm quite happy now :D

Anyhow, I now have a very good excuse to order a M.O.R.E. bushing and body lift kit which is cool, and I didn't end up needing a new fuel pump after all.

I also did the gas tank mod to up the capacity while I had it out. What a piece of cake.

So I guess if there's a moral to this whole thing, check your body mounts, and return lines if you have a high fuel pressure situation before you go buy a regulator, etc. I would have come out money ahead if I had checked the fuel pressure a long time ago, but it's all good since I upgraded parts that were upgradable through the process, etc.

Definitely was a learning experience, but man does she run sweet now.

[Jeffy]

Wow, that's a weird one.  Still good job.

[Red93YJ]

yeah, it had me stumped, but we're good to go now. Definitely was a first for me when I thought I had seen it all.