I have a '94 Escort that just outright died driving on the freeway a few weeks back. Now I finally have time to look at it and try to figure out what's wrong. I had a Cylinder ID Circuit Failure code initially but replacing the crankshaft position sensor cleared that code up. However, I still have a no start condition and the computer is giving me a 542 code. "Fuel pump circuit open, EEC processor to motor ground." Fuses are good, the relay has been swapped and neither of those things have made any difference. I've never had to troubleshoot a bad fuel pump before, so I've been trying to find what I can around the Internet to help myself out.

When the key is clicked on (not attempting to turn engine over), I can hear the fuel pump whir.

I'm not sure how to proceed. I've considered testing the fuel pressure, but I'm not particularly sure what the acceptable pressure ranges are. I also want to test power along the circuit down to the pump to see where I might have an open circuit. However, I'm not sure where the fuel pump wiring physically runs under the car. I also don't know where the fuel pump ground is located so I can check that for corrosion/damage.

Any help/advice that I can get would be greatly appreciated. I didn't want to just go drop money on a new fuel pump only to install it and find out the pump wasn't the issue. I wanted to (try) to do this somewhat correctly.

 

I believe the fuel pump pressure spec for your vehicle is 13-17 psi at rest/ idle.

 

I've been told a few times by people that I know that hearing the fuel pump whir when I click the key on doesn't necessarily mean that the fuel pump works. I'm not sure whether this is the case or not.

A response I got on another message board says that I should go through some pinpoint tests before I consider testing the fuel pump as the code I'm getting is likely pointing to an opening in the fuel pump circuit somewhere, whether that be the inertia switch, the ground, or just a place where the wiring has been damages. I checked the inertia switch when I was checking the fuses and relays and the switch wasn't kicked. The wiring looked fine at the connector, the rest was still wrapped and I saw no breaks.

I'm going to try the pinpoint tests and see where that takes me, but I was wondering if anyone could point me in the direction of the fuel pump ground location. I had read somewhere that it's located on the passenger side in the engine bay, and I was wondering if that was in fact where it was or if it was going to be underneath the car on the frame/chassis.

 

A suggestion;
Instead of trying to check all over the place, check for full power and ground as close as you can get to the fuel pump itself.Since those vehicles had their share of fuel pump troubles you could be looking for a fuel pump. You need to drop the tank to replace it. Here's the kicker, If the fuel pump has never been replaced and it is the original go for it ! When they do fail , it is usually with a full tank and a dog job to drop a full tank to replace the pump module.
It is a lot easier to drop an almost empty tank compared to a full one.
Also, before doing anything , confirm you have fuel pump pressure or not.

 

If I check for power at the connection to the pump, what will I be looking for? 12 volts? I'll be using a digital multimeter to check.

I also have seen somewhere that there's a way to access the top of the fuel tank through the back seat, which I intend to check when I go out to the car.

Yes, the fuel pump has previously been replaced. However, if I check for power at the tank and I have power all the way back there, then I would be led to assume the fuel pump is indeed the issue.

 

Two things to keep in mind;
Make sure you have a good ground at the pump, and ,you could read 12 volts at the pump even if you had 1 strand of wire bringing the power, make sure full power is available by measuring it with the pump running or load the wire with an item that pulls a few amps.

 

I have the battery charging right now, and when that's finished I'm going to test the connection at the pump. With regards to the connector that goes to the tank, what wires should I be testing for power?

Also, it would appear it has an in-line fuse.

EDIT: I have fuel pressure to the fuel rail, just shy of 40 psi. From what I understand the acceptable range for this engine is 35-45, so I'm within ranges for fuel pressure. So I'm getting fuel to the rail.

 

You could be on a wild goose chasing a supposed fuel pump problem. If you have fuel pressure, even enough for starting and maybe not running well,it should start. Suggest you check for spark at the plugs. Also, don't be afraid to look for and check for loose/poor ground connections starting at the engine and going to the computer.
One way to confirm whether fuel is getting there is to pull one of the plugs and see if it is wet with fuel. If so , start looking for a possible spark problem, starting with the "new" crank sensor.

 

I'm going to check for spark, I'll pull/check the plugs to see if they're wet with fuel.

I'm also going to check the timing. Maybe the belt slipped or something. The ground terminal connector at the battery does need to be replaced but I don't know if that's going to be the issue or not. I may just try it to see. Even if it ends up not being the problem the one on there right now should just be replaced before it is a problem. If all of that fails, I have no idea. Maybe I'll do a compression check to see if the motor is done for, but it shouldn't be. The car has a lot of miles on it but it also had the engine rebuilt not long before we bought it.

 

The checks you mention make good sense. Compression check should eliminate a few things , just make sure everything is lined up correctly when replacing the belt. They don't usually slip while driving, but they do when starting.


This has happened more than once and is why I will ask the question. Did you just purchase fuel a short time before the engine quit? I can recall several times when fuel was just purchased a short time later the vehicle quit running. If the plugs are wet try to light one of them and see if it will burn, if no that could be the problem ,,,got a load of water instead of fuel !!!