Engine stalls, seems to be fuel problem

[kclo4]

So here I was bleeding my brakes today when something unexpected happened on the test drive.The car started fine and ran fine for about a minute. I got on the gas a little to test my brakes and I went to stop hard the car wouldn't. I turned back into my neighborhood only to find that the wheel was hard to turn. Looked down at the tack and it was at 0. I can't figure out why the car would have died. I start it back up and after and it would not rev and after a few moments it died. This was repeated for the rest of the day.

Car starts perfectly fine, then bogs out and dies. It sounds normal till it seems like it runs out of fuel.

There are NO engine codes being thrown which is even more wierd.

If I start the car and give it some gas it will bog out heavily and hesitate. It will rev, bog, rev, bog but it never revs very far before it bogs.

In the troubleshooting I found that the fuel pump runs for its allotted time when the ignition is turned on, but it seems there is no fuel pressure after that initial surge. I haven't got a fuel pressure tester to find out for sure, but I will try that tomorrow.

We took out the fuel pump and gauge and the leads on the fuel pump show about 1Ohm which is in spec. The fuel filter does not appear to be clogged because we unhooked the hose behind the filter to test to see if the pump was working when the ignition was turned on.

This is all completely unexpected as I drove the car last 2 days ago and it performed well.

Any other ways to test the fuel pump or anything else that could be involved?

I did read one interesting thing in the FSM involving the camshaft position sensor. It seems like the fuel pump will not do anything unless the ignition is turned on or the camshaft position sensor is telling the computer that the engine is turning.

The car is a 95 S14 with stock engine.

Beyond this I am stumped. Any help would be great. Tomorrow I will play around some more, but tips on what to try would help out.

Thanks

Paxton

[s13sr20chris]

if its a fuel issue then isolate fuel to be sure. get some cans of carb clean and hook up to a vacuum hose. when car is bogging spray carb cleaner. combinations of carb cleaner and opening throttle should give you a car that runs good. also check the volume of fuel. pull hose off of filter and put in a coke bottle. turn key on and see that fuel gushes out. it should be filling bottle pretty quick untill it cuts off.

[kclo4]

So I found the proper brass fittings to make a T and have tested the fuel pressure between the fuel filter and the fuel rail.

As listed in the FSM, when the ignition is turned on the gauge reads right around 43PSI which is good.

After the pump charges the line the gauge drops down to about 40PSI.

When the engine in started the gauge reads about 40PSI and then fluctuates around 40PSI as the engine bogs out and dies. The FSM says the gauge should read 34PSI at idle. What could this mean?

I will do the vacuum pump test when I can borrow the pump dealio.

Any other tests that I can do with the pressure tester gauge or anything else that may help?

This all appears to point at the fuel pressure regulator but what do I know?

[s13sr20chris]

yeah, that is high. is your regulator hooked up? is proper vac getting to it? even then it should not be stalling out. will carb cleaner in a vac hose revive the motor when it is stalling?

[portisroads]

do 240s have a vent for the gas tank? could be clogged? what happens when you remove your gas cap and run the car? just an idea, works on bikes with clogged gas cap vents.

[s13sr20chris]

that is a good point although a clogged gas tank vent would ussually cause a vac in the tank and give lower fuel pressure on a carbuerated setup. our electric fuel pumps dont have as much of an issue with that. thanks for the good idea though.

[kclo4]

Forgot to post what happened with my problem. It's really retarded too.

My cone filter is one of the types with a second inverted cone in the end for added suface area. Well, the metal cap covering that busted off and perfectly seated into and clogging the MAF. Thats it...

Aparantly the car backfired and it started to run but didn't have any power. I guess when it backfired it pushed that disk far enough out of the way to get at least some air.

Of course I didnt discover the busted disk until after I replaced the FPR($20 used one at least). It backfired and started running shortly after installing the other FPR also, but not on the first try. It backfired the second time I started it with the new FPR, but I was giving it a lot of gas and it backfired.

Freaky stuff... Working on cars sucks, but driving them fast is fun.