So I have been battling this temperamental engine for a while now.
Today I went down to AutoZone and rented a nice fuel pressure tester so I could make sure the fuel pressures were correct with a cold car and when the fuel pump starts to scream.

However that flare fitting where the fuel is pumped into the rail is obviously not compatible with the pressure tester. I need a tee like this one: http://jaguar.spx.com/detail.aspx?id=876 to put in there.

I happened to have an old metric nut from my upper control arm lying around and it threaded onto the line pretty well with very minimal slop. I think it must be a 13mm. Can anyone confirm this thread size on the fuel line? Is it really metric and going to take an act of god to find a part to work that is less than 160 bucks?

I also went and rechecked my new TPS today. Its closed voltage was .46 and wide open was 4.6. Even with the throttle turned wide open and the stop screw removed it stuck at 4.6 so I think either my millimeter is funky or I am just getting jipped .2 volts. I also readjusted the throttle as it was not opening up fully and the marks on the bell crank were not matching up.

I took apart the IAC valve and cleaned it, it was stuffed with carbon. A test drive was promising. No lean chk engine light and the car drove and shifted like I had never felt before. It was great, however once that fuel pump started crying I had some loss of power.

Also when I turn on the a/c, the head lights, and the window heaters it drops in rpm and then comes back up to the 700 mark however that voltage gauge drops down to about 12v. From my understanding it is supposed to increase the idle when there is heavy load placed. It seems the car is correcting the idle just fine but not realizing that something got turned on.

My last problem I have is my electric fan. It never ever came on, even in 100 degree days with the temp gauge tipping past N. So I jumped it at the temp switch and it came on. I replaced the switch and it still never comes on. The fuses and relays are good. Would it be safe to suspend the switch in boiling water and test its operation?

 

You hired the tester, did they not have the adapters available with the kit?

Not sure what you are trying to test for, high or low pressure, but if you pull off the vac line from the pressure relief valve you should create high pressure.

Or if you think you have low pressure then squeezing the return line should give an increase of pressure (obviously don't do this for long).

If the pressure doesn't rise then your fuel pump is suspect, if it rises sharply then the relief valve is suspect.

Not very technical, but this is what I did when trying to find a fuel problem on my 92 a few years ago.

Then again, a screaming fuel pump is not going to be self healing, so you may have both problems.

A failed valve caused a cooked pump.?

Fan, 'motor, fuses and relays are good' faulty thermo' switch or wiring, replace.

Load test, have your Autozone test your battery, sounds like your alternator is doing some work as the rev's change under load.

Others will have better explanations.

 

Well the test kit only came with standard fittings. Not the female flare fitting needed. However I was able to rig something up today.

If you get some vinyl hose that fits over the flare end snugly you can thread the nut over it and create a good seal.

I wanted to do the test after I had been running around stop and go traffic but that was not possible. All of the pressures were well within range and the pressure regulator operated like it should. I can't test it when I am broken down on the road due to an overheated fuel pump or whatever is happening. I did squeeze the return line and the pressure skyrocketed.

Yeah thermo switch seems suspect, it is brand new though.

Also my throttle potentiometer threw an out of range code today. It is closed at about .49 volts but when the throttle pedal is to the floor it only makes it to 4.3. if I hand turn the throttle all the way it will get up to 4.6. Not sure how this is remedied. There isin't 1000 miles on the pot.

My battery was load tested at O'Reillys and passed not to long ago. The haynes says revs are supposed to increase under heavy load due to extra work placed on the charging system. This isn't really happening it is just ensuring it stays at it's idle speed.