Hi, everyone. This is my first post here (however, long time troll). Here's what I'm currently dealing with...

My 240 sat for a while, and it was time to smog it. It ran fine to the smog station, but drove the car 100 ft down the road after getting it smogged and it died. Had to tow it home. Here are the details:

- 1990
- Cranks, but will not start
- Has spark
- Fuel pumps not operating

What I've done so far:

1. Replaced fuel pump relay. It clicks when I turn the key to "on".
2. Replaced in-tank fuel pump. The old unit had a torn sock.
3. Replaced the in-line fuel pump and fuel filter. They looked pretty nasty, so I just replaced them for good measure.
4. None of the above fixes worked, so I jumped #4 to #6 fuses. This turns on the in-tank fuel pump, but not the in-line. It still won't start.
5. Replaced main fuse in engine bay.

Any ideas? Thanks for the help.

 

the fuel pump relay has two seperate relays. one relay comes on with the ignition key and stays on, this provides power to the ECU, the injectors, and most of the rest of the fuel system.

the other half comes on when the ECU says to, and powers both fuel pumps. it should come on for about 1 second when you switch on the ignition, then turn off again until the engine cranks over and the ECU sees timing pulses, then it should come on again and stay on til about 1 second after those timing pulses stop.

when you said you jumped fuse 4-6, was that with the fuses in place or with fuse 6 removed ? with the fuses in place, the pumps both should have run, if the main pump did NOT run, then its a defective main pump, and the engine will not work because there is no fuel pressure.

 

Crankshaft Position Sensor?

 

wouldn't be any spark if there was no CPS.

 

Thanks, Pierce.

I jumped it without both fuses in first, then with #6 removed, per some other recommendations on here I found while searching.

I'll jump it again with both fuses in and see if that works. If it doesn't, I'll run a bench test on the pump (it should work, it's brand new..)

If things work with jumping, but don't work without a jump, could it be an ECU problem?

 

with fuse 4 removed, if you jumper fuse 6 (always hot) to left side of the fuse 4 holder (with the ignition off), only the main pump runs, if you jumper 4 to the right side of the fuse 4 holder, then the tank pump runs. I use a small alligator clip jumper for this, so I can get out and go around and listen to the gas tank filler (with the gas cap removed) to hear the in-tank pump running (its harder to hear if the tank is more than half full).

 

 

what did you use to replace the fuel pump relay? I believe the 'good' ones are Steibel, which has a logo like a circle with a $ in it.

 

Normal culprit for these symptoms is the fuel pump relay. Check to make sure your replacement is good. Usually I just pop the top off of it and re-solder all of the joints on the little circuit board.

If the relay is known to be good, another (remote) possibility is your ECU. The famous "pink label" ECU than has a part number that ends in -561 has been known to have issues with the fuel pump circuitry. In '90 they started using the "white label" ECU that has a part number ending in -951 that fixed the problem. It has been my understanding that the pink label ECU was used in '89 but who knows, maybe a previous owner swapped in an older ECU. They are interchangeable.

 

I pulled the relay out, and tried to start it with the jump (both fuses in, 4 to 6). The car cranks, but it doesn't start. The in-line pump works.

So, it runs with the relay in and the jump attached.

Generic, Amazon. I'll order a replacement Steibel and pop the top off of the old one and resolder it to see if that makes a difference..

Thanks.

 

the fuel system relay has TWO relays in it, the first half is switched on by ignition, and provides power to the ECU, injectors, etc etc. the other relay in it powers the fuel pump and is what the fuse 4-6 jumper bypasses... so you'd need to jumper BOTH halves of it to run without it.

 

Well, I replaced the generic relay with the Stribel one. And... no luck. Still needs a jump.

 

then its probable the fuel pump relay output of the ECU is fried

next step is to remove the interior panel on the right side of the passenger footwell, the ECU is behind that, and read which version ECU you have. They are all Bosch 0 280 000 XXX .... per https://www.volvoclub.org.uk/faq/Eng...ReferenceChart the -561 pink label versions are problematic, these were used on 89-92 LH2.4 systems (both 240/740/940).

replacement ECU have to be for LH 2.4 cars (1989+ non-turbo 240/740/940, or 1990+ turbo 740/940), and they should match your (EGR, Turbo) (meaning, no EGR or Turbo, or EGR w/o turbo, or no EGR with turbo, or EGR with turbo. California cars have EGR, others may or may not. if your car does not have a cold start injector (I'm pretty sure most 940's didn't), then the ECU can't require one, or you'll have trouble starting in cold weather. if you DO have a cold start injector (this is a 5th injector that sticks into the intake manifold) you can still use an ECU for a non-CS car, it will work fine, just not using the CS injector.

 

Just closing the loop on this one; it was an ECU problem.