When driving for more then 10-15 miles the car will stall and shutdown. After waiting for an hour it will start right back up again and go that same 10-15 miles and do the same thing. I've seen this happen 5-6 times in a row. The fuel filter was just replaced and the fuel filter relay is running fine (I can still here the buzz after it's died). The vacuum hose on the fuel pressure regulator was loose and has since been replaced as well. This has become quite a nuisance as you can imagine. I can seem to figure out what else is causing the problem other then the things I've already checked. Any input would be appreciated.

 

Have you done usual tune-up? Spark plugs, distributor cap, rotor, air filter, spark plug wires? Go to www.stepbystepvolvo.com and take "Real-Life Volvo Quiz." Could help you.

 

What year, what engine?

 

It's a 1991 2.3 V4 B230F

 

I checked the rotor and noticed it looked faulty and replaced it thought it would be my saving grace but unfortunately it's still not running properly. I can't even seem to get the plugs loose and don't wanna bother with them at the moment since they are putting out spark and don't wanna strip out the fitting. I've got a new air filter and the cap is fine. It seems to be more of like a component getting to hot or something to due with a fuel line. I don't know I'm pretty much stumped at this point.

 

I'd find a junkyard with some volvos and replace the ECU (brain). You'd be suprised. I've gone through 3. The last one I put in was the best and fixed all sorts of weird stuff like rough idle etc.. The junkyard here in oceanside CA has several and they ask $30 for them. My referred mobile volvo guy charged me $100 and it was a bad one!!!

 

If I recall there are two temperature sensors one for the temp gauge and one controls the cold start injector through the ECU (and it's very hard to get to) Since it's summer it should start without the cold start injector hooked up, unplug the injector and see what happens.

 

It could be a bad ECU. But my first suspicion is a bad crank position sensor (RPM sensor). If it's original I would replace it just on general principles. It's located on top of the bell housing where the tranny bolts to the engine. Hard to get to. You can see it or you can feel it, not both at the same time. Do not break the mounting bracket for the CPS or you will have to drop the tranny.

Agree about disconnecting the cold start injector. Probably won't help but it can't hurt. It is only activated below 5 degrees F and while cranking.

After the CPS I would suspect a bad coolant temperature sensor. It's located under the intake manifold near #3-#4 cylinders. Hard to get to without removing the throttle body.

 

I'm able to get the engine to go into its failure mode easily now in the garage, instead of by driving it out on the street.If I run the engine for 12 minutes plus or minus a couple of minutes, it will die out every time.

This time I attempted to check for spark by hooking up my inductive timing light to the #1 plug wire and had enough wire to reach the drivers seat so I could trigger the light and hold the key at the same time. When I turned the car over to try and start it the light flashed evenly, but the engine wouldn't fire. I'm assuming at this point it means I have spark. The plugs are stuck on this car and I'd rather not risk further damage trying to get them out for troubleshooting if I can avoid it right now.

After about 1 1/2 hours of cool-down time the car will start, and run for another 12 minutes before dying. I've repeated this four times, in the garage, in the direct sun, hood up, hood down. No difference.

I think I should probably check fuel pressure when it dies but I don't have a fuel pressure gauge yet. I did replace the fuel filter, and a very loose vacuum hose on the fuel pressure regulator but these two things have not made a difference. I spotted the crank position sensor after a lot of searching, behind the engine as was posted. Is there one bolt, or two holding it? I could only see one but I need to let the engine cool completely before trying to get my hand stuck back there. This stalling out is so regular I'm beginning to think its likely the ECU, ideally it would be nice to swap this one into another running car or vice verse to test it.

 

Have you read any fault codes? LH 2.4 has a diagnostic unit to check fault codes stored in the ECU. Is your check engine light (CEL) on? If you have spark the CPS is probably OK. The original ones are unreliable after 10 years. If the ECU doesn't detect the crank pulses it will kill the spark and the injectors. Sure sounds like the coolant temp sensor. A fault code of 1-2-3 with CEL on confirms.

 

No check engine light.
No trouble codes just 1-1-1

 

Well turns out the ECU wasn't the problem. I swapped out my out 561 for another and the car shortly died in the same amount of time.

 

My old 740 GLE had a B230F and it was an I4 (inline 4). Very strange problem. The humming you hear should be a fuel pump. My 740 GLE had 2 fuel pumps, 1 in the tank and the other under the car.

Sound to me like you are getting a VAPOR LOCK. Do you think the fuel filter was installed properly? It's not backwards is it?

 

sometimes...the coil will break down with heat and short out, if you have access to a heat gun/hair dryer will work in a pinch..apply heat directly to coil and see if car quits long shot but worth eliminating.....also heat ecu as well

 

The fuel pump is operational and the fuel filter was installed by me and was put in correctly.

 

I will try this later today and report back on my findings.

 

Are you getting 1-1-1 for both the ignition (socket 6) and fuel codes (socket 2)?

Sure sounds like you are loosing spark ... CPS or the power stage on the fender. I can understand not wanting to remove a seized plug so use a spare wire with a spare plug instead and watch the spark. My guess is its strong enough to trigger the light but too weak to fire the gas.

The power stage has a metal heatsink that requires paste to dissipate heat. If it overheats you'll loose spark. A new crank position sensor is $35 from FCP Groton.

 

Just read thru this whole post and didn't see anyone mention the fuel pump relay (FPR). Symptoms would indicate that to me...

Philly ckd spark with his timing light; was still getting spark during failure mode...

I would find the FPR, find which terminal gets pwr to the fuel pump(s), wire up a test light (or meter) to it, and see if you still have pwr in failure mode. Now if it goes out (looses pwr) then it still could be the ECU (which actually energizes the relay to turn it on..) but since you already tried another ECU, that's probably not it. If you understand how relays work, you can ck to see if you're getting energize signal from ECU during failure mode.

 

UPDATE:

Fuel pump does not prime when key turned on..

Does the ECU alone control the function where the fuel pumps are activated for a moment when the key is turned on, before the starter is energized?

Swapped ECUs with another pink label 561, also swapped fuel pump relays. Both parts unknown quality, from friends parts car.

First time with other ECU and relay it ran and then died after 12 minutes just like before.

After fiddling with cable connections to crank position sensor (to investigate how hard it would be to remove) AND hot wiring fuel pumps on at fuse block (wanted to prime fuel rail before starting) the car idled for an hour with no issues, until I shut it off. Halfway through this period I removed jumper from +12 to fuel pumps, engine continued to run. After I shut it off it would re-start but a little difficult because fuel pump not priming. Fuel rail not holding pressure either I noticed, slow bleed down . Glad its no longer cutting out after 12 minutes but I need to do more testing with the 2 ECUs and F.P. relays. Hard to believe just unplugging and plugging crank position sensor would make a difference. I need to see if old ECU goers back to previous failure mode where it would die after 12 minutes. I now have two flakey ECUs? Intermittent crank position sensor sensitive to pulling on cable?