01 fuel system problem

Hello, I've been on this forum for this car, for this same problem before, but this time it's a little different. Last time the car wouldn't stay running at certain angles, then stopped altogether. found a loose wire and it was fixed.

This time I can hear the fuel pump come on when I turn the key but it will just go clunk or start to pressurize the sytem and then stop. The car won't even crank after that. If I turn the car off and then on several times the pump will kick in and the car will start...so far. I'm afraid it's going to start dying again on me. Any ideas where to start? So far I've replaced the relay and the fuses but no change. I hate to think of dropping the tank to replace that fuel pump but if I have to...

thanks
escort

...but it will just go clunk or start to pressurize the sytem and then stop. The car won't even crank after that.

Are you saying that sometimes the starter will stop turning over the engine at the same time the fuel pump stops pressurizing the system? If so, your issue is something other than or at least in addition to the fuel pump. The fuel pump relay is not tied to the starter relay.

It sounds more like you possibly have an issue with the battery or connection to the battery. Make sure both cables are clean and tight at the battery and where they connect (engine block/relay/fuse panel). Check the battery voltage when the starter stops cranking while the key cylinder switch is held in "Start."

-Rod

no, sorry I wasn't clear before. I'm saying that if the fuel pump doesn't run for the two or three seconds it takes to pressurize the system then the car won't crank at all. No click no nothing. It seems that without pressure to the rail the car is made not to crank under those conditions.

I'm starting to wonder, since it's positional, meaning it depends on the angle of the car, if the filter isn't at fault here. I can park the car on flat ground and it almost always starts. But an angle, any angle, and the fuel pump stops after less than a second if it starts running at all. I'll change the filter this weekend and see what happens.

BTW, the battery and cables and starter relay, along with the fuel pump relay were all changed last winter when I had this same problem. So they should be fine. I've just about come to the decision it has to be either the fuel pump or the filter. Hopefully not the former as the tank is full right now.

Escort

The starter is in no way connected to the fuel pressure. If you don't have fuel pressure, the starter should still attempt to crank the engine. Sounds like you have an electrical issue cutting power to both the starter and the fuel pump. I don't have a service manual for the 2001, but I'll check my manual for the 2002 model year.

I suspect it will point to a Digital Transmission Range (DTR) sensor (common to cause issues), ignition switch, multifunction switch, or key cylinder switch.

-Rod

Well, I'm a little unsure of my previous post. According to the wiring diagram for the '02, the ground of the starter relay coil is provided by the PCM. So, in theory, the PCM could prevent the starter relay from engaging. However, I don't expect this is the reason for the PCM controlling the ground. Instead, I think the PCM connection is strictly to prevent unauthorized start attempts as detected by the SecurLock or PATS system.

In my mind, the DTR sensor is still high on the suspect list, but I'd like to add the SecurLock/PATS system to the list as well. I guess I shouldn't exclude the PCM relay either.

Do you happen to have another programmed key that you could try for a few weeks to see if that prevents the issue from occurring? Do you know if your car has SecurLock/PATS?

-Rod

yes the car does have pats system. Last year I tried to use the other key, but there was no change during that problem. I'll get it out tomorrow and try it this time. Unfortunately therte isn't any way to predict when this problem will occur so it may take a while before I know if it worked or not. Also,FYI last year I removed and cleaned all grounds.

I looked back at my records and I changed the DTR last year while I was changing everything else. So I doubt that's part of the problem. Currently I'm using the spare key, I'll let you know what happens.

thanks

the spare key made no difference. The problem recurred yesterday afternoon. Car eventually started, but I had to turn it on and off three or four times before it cranked.

You'll probably need to instrument the fuel pump wiring. Ideally, this would be done at the pump, but I don't think that is practical, so instead tap in at the fuel pump inertia switch. Sometime when it won't start and the fuel pump doesn't run, check for voltage to the fuel pump. If there is voltage to the fuel pump, but still the fuel pump doesn't run, you most likely have a faulty fuel pump.

If there is no voltage to the fuel pump when there should be, then you need to start tracing the circuit.

Keep in mind that you will have to monitor for voltage when you turn the key to run within the first couple of seconds, when the pump would normally be pressurizing the fuel system.

Since you loose the starter as well, I suspect that you have an issue other than the fuel pump. More likely, your PCM relay is not staying closed during certain start attempts. I think that would be about the only item common to both the starter circuit and the fuel pump.

-Rod

Still working on this problem. what if it's the PATS module in the door? The other day I was driving home on the interstate, and going up a slight grade the car just shut off and the theft light came on. I don't know if the theft light would come on if it were just a condition that caused the car to die because this is the only time it has happened.

But I pulled to the side of the road, put the car in neutral and turned the key off and on twice and the car started.

Yesterday I put the car in the garage and changed the fuel filter. The garage is level. When I went to start the car it wouldn't crank and the fuel pump didn't power up. The one place I didn't check grounds and power supply is in my door for the pats module. Don't see any way out of figuring this one out I can't trade a car that won't run. So any help is appreciated.

Escort0526

It sounds like you are not afraid to dig around in the car. I'd suggest you pick up a service manual for your car. I don't have one specific to the 2001 model year, but if you visit the Taurus forum mainpage, there is a sticky regarding downloading factory service manuals. They will have the full wiring diagrams and component locations that may help you track this down.

Another option would be to find someone with a professional scan tool that can access the PATS computer and check for codes.

-Rod

I was forced by necessity to give up on the quest to find out what was wrong with this car. with this brutal winter and the complete unreliability of this car, I traded it in for a new dodge caliber. Thanks for all your help with this one. Wish I could have solved the mystery. The caliber at least has a warranty for the next few years. I hope I never need it.

thanks again
escort0526