lovemyp-car

have you tried shooting starter fluid in to see if it will actually fire? it's weird that it died at a light...try starting it with the fuel pump jumpered also, that will tell you for sure that the fuel pump is coming on when you turn the key. Is it possible your new DME relay is bad? maybe it's giving a very weak connection.

ps. i don't think a bad fuel pressure regulator will keep a car from running, i may be wrong, but i would think that it would just make the car run poorly

shiners780

I've got a compression tester if you want to use it.

roman944

don't know, all I see is that Clark's mentions it as one of the causes of no-start

just like the fuel check valve on the fuel pump

now, the first time we ran the fuel pump for 30 secs gas came out kind of beer-ish color

we just re-did it through the FPR and the gas was coming out clean like lemon juice ...

starter fluid? spray it where?

Jim - sure - if you happen to have free time in the next few days

Van

Bad gas? I've seen it happen before.

roman944

I don't know

kind of strange though

still don't know what to do/try now?

compression test ... why? what would that show me? my belt did not skip any teeth

every time we crank the car, we get a good strong smell of gas, especially out of exhaust area ...

rgs944

A compression test will tell you if a hole is weak. You could have a hole burned in a piston or a broken valve. Simple to do the thumb test and find out quickly if there is a major problem that is leading to very low compression in one cylinder. If all four holes feel strong then get some starting fluid and see if it fires up. Spray it in the air filter.

Mark944na86

Try changing your fuel filter, if you haven't done this since owning the car.

roman944

alright guys, I'm placing a nice order with Pelican today - fuel filter, check valve, level sending unit, I'll get new spark plugs and a new DME and maybe a couple more little cheap tid-bits

oh yeah, it appears that a fuel pressure gauge is a REALLY handy tool, since its mentioned all over Clark's ... so I'll order one from Lindsey Racing (cheap and faster shipping)

in the mean time, I'm not sure when Jim will have free time so I could get my hands on a tool to check compression ... but would Autozone have it? is it straight forward how to use it? I'll probably be asking for more help once I have it in my hands ... LOL

rgs944

Very easy to use a compression tester, and any auto parts store will have one. You need to get that done so you can eliminate some very bad stuff, then go from there. When you have it in your hands all you need to do is put it in the spark plug hole like you would a spark plug. Crank the engine and see what it says. Do this for each cylinder.

Van

Take out all 4 plugs, and hold the throttle WOT (butterfly fully open) while cranking the engine for 4-6 revolutions.

Most compression testers have a little valve so they "hold" the reading.

rgs944

Van, why do you hold the throttle open? I am not questioning whether it is right or not. I just have never heard of that before.

Mike C.

There is a pressure drop across the throttle plate when closed (I don't know how much). The idea is that the cylinder can pull in air unrestricted with the plate open.

AScholtes

also, most FI systems cut fuel while cranking with the throttle wide open. Its to clear a flooded condition in the cylinders.

rgs944

What should the range of compression be for the average NA engine?

kingston944

Well you need at least 100psi or more the better.