740 GLE sometimes won't start ?

Wow- a rash of 740's these days! Cool!

I had my engine (B230F) pulled and the lower half rebuilt. When we reinstalled the engine, it would only crank with a shot of ether. Make sure your fuel pump relay is good. That's a biggie.

There was something else....brain freeze. Sorry - more tomorrow.

Mark Bratcher wrote:

Happening in warm weather really focuses suspicion on the fuel pump relay. The solder connections between the relays and the circuit board inside the housing fatigue and crack, making the fuel pump operation intermittent. Warm weather makes it worse, for whatever reason.

The pc board in the relay module can be resoldered or the relay can be replaced.

Mike

Had the same or similar problem with 940 GLE, I changed the "Fuel pump relay" (sometimes called "fuel injector relay") and now it is somehow OK.

Thanks everyone for your input.

I pulled the fuel injector relay and resoldered all the contact points. I'll see how it goes!

Mark Bratcher wrote:

Well... I resoldered all the soldering joints in the relay and it operated OK. But today it's 95 degrees and while I was stopped at a light the car just died and wouldn't start (same symptoms). I pushed the car to the side of the road and it finally started after maybe only a minute.

Any other thoughts? Perhaps it just needs a new relay or something?

For about $21 you can know for sure:

FCP Groton is a trusted name in auto parts. Nick Bauer is very helpful. Also, check all of the fuses.

G'luck, Jamie

Mark Bratcher wrote:

B230F is 8-valve not 16-valve. Try the Radio Suppression relay, usually attached at the side of one of the suspension strut towers. This feeds the power to the injectors via a block of four resistors. Check for power to the resistor block before checking relay. It has almost precisely the same symptoms as the Fuel Pump relay.

All the best, Peter.

700/900/90 Register Keeper, Volvo Owners Club (UK).

Thanks Peter and Jamie.

This is strange indeed.

The car used to very infrequently have trouble starting. Now that I've secured all the solder joints in the injector relay, the thing stalls while driving about every 5 to 10 miles. I have to coast to a stop somewhere and wait for it to want to start again, usually a couple of minutes.

Tonight when I got home after driving, I when to pull the relay again and the injector relay, as well as the two small ones in front of it, were very hot. Not enough to burn your hand, but very hot nonetheless. More than I would expect. This relay looks pretty simple, and I don't see anything wrong with it on the inside. It's just a couple of coils etc and looks pretty clean.

I can try a new one as well as a radio suppression relay. But I am puzzled by the connection in events between my fooling with the relay the first time and this sudden frequent stalling issue. And I'm no slouch when it comes to soldering. I don't get it. :-/

I appreciate all the help. This is a great news group with very knowledgable people. :)

Mark

Peter K L Milnes wrote:

>

Thanks Peter and Jamie.

This is strange indeed.

The car used to very infrequently have trouble starting. Now that I've secured all the solder joints in the injector relay, the thing stalls while driving about every 5 to 10 miles. I have to coast to a stop somewhere and wait for it to want to start again, usually a couple of minutes.

Tonight when I got home after driving, I when to pull the relay again and the injector relay, as well as the two small ones in front of it, were very hot. Not enough to burn your hand, but very hot nonetheless. More than I would expect. This relay looks pretty simple, and I don't see anything wrong with it on the inside. It's just a couple of coils etc and looks pretty clean.

I can try a new one as well as a radio suppression relay. But I am puzzled by the connection in events between my fooling with the relay the first time and this sudden frequent stalling issue. And I'm no slouch when it comes to soldering. I don't get it. :-/

I appreciate all the help. This is a great news group with very knowledgable people. :)

Mark

Peter K L Milnes wrote:

>

Mark, thank you but I must defer to the veterans here. Honestly, I am a newbie here who only knows the little I know, thanks to the kind, knowledgable and intelligent Volvo owners who have been here long before me.

I have probably learned 75% of anything I know by reading here and the other 25% by trial and LOTS of error.

G'luck

Jamie

Mark Bratcher wrote:

>>

I've said this a million times before, but how's the engine wiring harness? If it's original and the car is pre-1989, it needs to be replaced.

>>

Here's some food for thought. THere are two fuel pumps in the system. A;pw pressure pump in the tank that provides a solid column of fuel to the main pump. This is to prevent the main pump from cavitating during acceleration in any direction as well as ensuring that the main pump lubricating fuel supply is always present. Although the car will run with the prepump not working it can hesitate and stall during normal driving maneuvers. Ultimately the bearings wear in the main pump causing it to draw more current than normal, but not necessarily enough to blow the main fuel system fuse.

Bob

I e-mailed Dave Barton and bought a used harness from him not when my car died, but when I reached under the hood to grab a hose and my car started!

The wires were so worn that I touched two wires and turned the car over. SCAREY!

James Sweet wrote: