Also as an piece of information for other people with the intermittent stalling curse:

The tank is pretty much empty, and things are for sure worse with an empty tank.

 

Hey, my thread has been hijacked, what gives...

My radio suppression relay is due to arrive in the mail today (ordered from Dave Barton). Yesterday I couldn't even get the car to start, so the situation is getting worse for sure. I'm hopeful that swapping in the new relay will give me good results.

 

that definitely points towards the in-tank pump and/or pickup hose and/or sock.

if you buy a non-Volvo in-tank pump, careful, many are wired backwards for unknown reasons.

here's a great how-to.
Volvo Fuel Tank Pump/Sender Replacement

He's doing a Regina pump, but the Bosch style pump is very similar as far as getting at it and replacing it. note its a completely different actual pump.

 

Installed my new relay today and took the car out for about an hour of mixed driving (basically ran a few errands). It seemed to be driving fine, no stalls. But after stopping at the bank, I came out and the car would not start. I cranked it 3 or 4 times over the course of a minute or two and nothing. Then waited another 30 seconds or so, gave it another crank and it started. So I'm not sure if the old radio suppression relay was bad or not. Kinda feel like I'm back to square one.

This reminds me of one of the reasons I got on that particular relay instead of the fuel pump relay, which had also been suggested. The guy at my Auto Zone told me that the fuel pump relay could not cause my intermittent stalling. He gave me an analogy of a relay being like a light bulb - once it goes out, it's out. It doesn't work sometimes. So he said I'd be wasting my money if I bought a new fuel pump relay. He had me convinced, but now I'm wondering if it's not worth the 50 bucks to find out.

Keeping in mind that one of the check engine codes I pulled indicated a fuel injector problem.

 

nah, the fuel pump relay can go intermittent too. as can the fuel pumps. I've seen them where they don't want to switch on, but once they ARE on, they will stay on til next time.

Auto Zone and other bigbox parts store employees are not exactly a reliable resource. their last job could have been 7-11 or shaking fries at McD's.

when its not starting the thing to determine is if its fuel or spark. crank it a few times, then pull a spark plug, inspect it. if its wet or damp and smells like gas, then you are probably getting fuel, so you probably have no spark. put the wire back on the plug, hold the side of the plug against a good grounding surface on the engine while someone cranks for you, ensure you get a nice fat spark-spark-spark.

 

Mr. Blabla, did you ever change that CPS?

 

No. But like I said, I got a 1-4-4 engine code which pointed to the fuel injection, so I thought I'd look at the relays first before changing something that isn't directly related to fuel delivery.

 

I was inclined to think the same thing about the Auto Zone guy, but when I questioned him he gave me a little speech about how he has "24 years experience as a tech", etc and that I should trust him. The relay definitely couldn't be the problem. So I gave him the benefit of the doubt.

This is a good tip, I'll give it a try. Thanks.

 

BlahBlah,

never intended to "highjack" your thread...just thought we don't need two
92 740 intermittent stalling threads.

Anyway here's how the saga continues:

I dropped the car at my mechanic to replace both fuel pumps and check the other components of the fuel delivery.
To do this myself unfortunately would be beyond my capabilities...

Today he calls and tells me that the previous owner must have glued the fuel pump assembly together and that he would refuse putting the new pumps in without me signing a paper that I am on my own.

He also mentioned that the cables of the assembly are rotten and that he found glue in the fuel lines?

All this sounds rather bad to me, and I am pretty surprised that fix actually was holding up that long (+9yrs)

As of his recommendation, I am biting the bullet and get the whole fuel pump assembly replaced.

This must be / should be it!
If the car still stalls after this one, I'll push it over the deepest cliff I can find.

 

"Glued together"? I'd not let this mechanic touch this or any Volvo.
You WILL be pushing it off the cliff as chances that your troubles are caused by fuel pumps are pretty remote...
Sure sign of incompetence when they want to replace BOTH pumps! What are the odds of that both are faulty? Nil!

 

The mechanic did not glue the pump into the pump assembly.
The DIY previous owner did, 9 years ago...
The mec. was as horrified as you and me. That's why he refused to install the pumps into the current assembly.
Therefore a new whole assembly got installed.

Will pick the car up, drive it and report back.

 

Just an update for anyone who might be curious. I changed the radio noise suppression relay and it had no effect. Then I changed the fuel injection relay. It's been a little over a week and the car has not stalled once. So that appears to have been the problem.

 

Dam Volvo's.

Reliable my ***!