240 Gl fuel problem.
Hello,
New to this forum, so here goes. I own a 240 GL, 1987 model with B230F engine and the L.H. fuel injection system.
The problem I,m having is starting the vehicle after being parked up overnight. The engine cranks, fires the dies. Then cranks and runs fine from then on. Always starts when hot.
Had the return hose off the regulator, and with the key turned to the "on" position, there is non fuel at that point.
By bridging the number 6 fuse to number 4, and activating the fuel-pump, (can hear it tic-ticking), fuel pressure is restored, and the engine starts fine on first start up.
Question is, should the fuel pump activate when the key is turned to the "on" position, or only when the key is turned further to "cranking" position?

I assume the wiring must be OK to, and the earth good at the pump, since I can hear it working. Any ideas?
Thanks in advance for any help here,
regards Masseynut.

 

The pumps only run when spark is present. Be sure to clean the blade fuse on the fender by the coil.

It could be this:
1985-1993 Volvo 240 Fuel Pump Check Valve | Volvo 240 Parts

 

I think he means, should the pumps run for a second or two when turned to the "on" position, and yes, they should.

How long does she idle on the first start up before she dies? I wouldn't think the engine could even run with a lack of fuel pressure, and then start up and run fine on the next try. Kinda just sounds like a rough start up on the first try before it warms up.

 

indeed, the pumps should run about a second when the key is switched on, then shut off until the ignition signals that the engine is turning over.

its possible the one way valve after the main fuel pump is bad, this valve keeps the pressure in the system after the pump goes off. its also possible your fuel relay is funky and somewhat erratic/slow/sticky (on a 240, this is behind the glovebox).

 

Maybe for a LH2.4 car, but my 86 LH2.2 does not do this.

RWD - No Spark no gas no run

 

Hmmm...

 

Thanks for the reply. On first start-up in the morning, the engine runs for a second or two, then dies. Then on the second start-up, the engine will usually keep running (most times).
I had read somewhere that the accumulator fitted to the fuel pump, is only supposed to keep a head of pressure fuel in the line, while the engine was "hot", thus avoiding an fuel air lock when it vaporizes in the supply line, due to the heat in the engine bay.
Does the pressure bleed-off in time, or should this "check valve" maintain a head of fuel in the line, even after being parked up over-night?
Thanks again for your interest,
Evan.

 

Not sure about the fuel accumulator and all, but it just seems odd that it will start and run for a second or two, and then die. It really does not sound fuel related to me. It should not even start with lack of fuel pressure because those pumps should deliver the right amount the first time, but that is just me. Sounds like you have some serious carbon build-up or something that needs a start or two to get over. Do you start it the first time without giving it any gas?

 

indeed, you shouldn't have to touch the gas pedal to start any fuel injected car that's in good condition. in fact, giving them gas often floods them.

massey; ideally, the check valve holds some fuel pressure for a couple hours at least. there's no 'accumulator', I think the pressure is supplied by the fuel pressure regulator and the hose, the valve simply keeps the pressure from releasing back through the fuel pump and into the gas tank.

 

Yeah, I'm gonna remove that check valve, and see if it's OK.
The problem can't be spark related, cause, when I hotwire from terminal 6 (always hot), to terminal 4 in the fuse box, the pump starts tic,tic, ticking, and it fires right up when stone cold. It even idles smoother.

 

if jumpering the fuse box like that works, its highly likely your fuel pump relay is defective. this is behind the glovebox, and is proabably a doublewide dual relay (the other part of it switches on the fuel injection itself).

 

Yep, already replaced it.

 

Hi, thanks to everyone that has replied to my original posting. I have sorted out the problem.
I established that the pre-pump/ main pumps only receive power when the engine is being cranked.
Then, by accident, I happened to notice a mix of air in the fuel, when I had removed the fuel supply line from the injector rail on top of the engine.
So I figured that somewhere on the suction side of the main pump, there must be a loose connection or a split/perished hose, or something similar. All external hoses checked out OK.
So then I removed the pre-pump/ sender unit from the tank. The filter(sock) on the pick-up pipe was squashed flat from sitting on the bottom of the tank, as well as a small split in the little connecting pipe on the pre-pump.
As there was not a dint in the bottom of the tank in the vicinity of the pick-up, I can only think that the sock filter has been this way since new. (198,000 kms on clock now.)
I made a small plate, drilled and fitted it to "lift" the pre-pump up approximately 1 cm from it's original position, fitted a new filter, which now allows the fuel to be drawn throughout the entire filter, and replaced the small hose.
Before starting the engine I attached a pressure gauge on a tee piece, in line from the supply pipe to the fuel rail, just to check the pressure. Started engine and had 32 PSI. Left the gauge attached overnight, and checked the pressure this morning. It had dropped to 15 PSI, but, guess what!!!, the engine started perfectly, first hit!!! And idled better, and has more response when the pedal is tramped, than it's ever had.
So the problem has either been a restricted fuel supply from the filter, or it's been pulling air thru that split pipe. The pipe should have only come into play, if the fuel level had dropped below the pipe height, I would have thought.
Apologies for the long winded response, but thought you all might be interested. Thanks again for all your help,
Evan.

 

A spit connection between the pump and sender line in tank will deliver air when half or less causing sputtering, but should not have affected anything on startup I would think. You say it was more than half full though right? So that would be masked a little, but a clogged sock will restrict it all, so, yeah. I hope when I replace the pump and sock in mine my lack of power will be acquited also. Glad you jumped in and got her fixed. Now onto that other problem...