Good Day All- can anyone tell me if there is a fuel safety disconnect on the 940 B230FT engine. I experienced a stall situation and it is believed that the reason the car will not restart is possibily due to a safety disconnect. The car cranks but will not turn over. The pumps can not be heard when the ignition is in the on position.

Best Regards.
Vbr60

Open the oil fill cap and observe the cam when someone cranks the engine-- does it turn? If not, your timing belt broke.

Good luck!
--
Herb Goltz, Aurora, Ontario, Canada '92 245 140K mi, '92 945t 210K mi

Dear Vbr60,

Good a.m. and may this find you well. I suspect the RPM/Crank sensor - mounted on the bell housing, at the 10 o'clock position, as you face the engine - has failed. To be clear, the sensor is mounted just behind the rear corner of the engine on the passenger's side of the engine.

If this sensor's signal is lost - due to deterioration of the wiring harness (heat/time) that lets the wires touch - the ECU causes the fuel pumps to shut down.

This is a safety feature: if the engine stops turning as a result of a collision, the fuel pumps will not be able to send fuel along tubes that could have been torn open by the collision. The fuel pump shut-down cuts fuel-fed fire risk.

The key clue: the fuel pumps do not spin-up - for one to two seconds - after you turn the ignition to "on".

If the sensor is the original, it doesn't owe you a penny. Here's a test. While someone tries to start the car, wiggle the wiring harness (the connector is just below the main engine bay harness, on the firewall, just below the hood gasket.

If the car restarts, even briefly, the sensor is worn-out. Replace it. See the FAQs, for the procedure. If you have enough 3/8" or 1/4" socket tool extension bars, this should take about 30 minutes, at most.

Indeed, as the sensor is 13 years old, if it has not already failed, it will do so. Better to change it now, than to have it fail, at a time/place almost certainly not of your choosing.

Hope this helps. Pls. post back with your findings.

Yours faithfully,

Spook

Spook,

Many thanks and may the universe reciprocate!

In accord with my nature, reaching out to those who know more on a particular subject than I do has proven once again to be a wise decision. As you are aware, there is no shortage of folks who offer advise that has not been tested.

Your recommendation of wiggling the RPM sensor wire harness worked with just one wiggle. The crank positon sensor cable appears to be brand-new however upon closer inspection breaks in the harness wire insulation were observed. An after thought is that the battery tie-down on this car is missing, I'm wondering if shifting of the battery's position during turns or braking is putting unnecessary stress on the wires. I'll correct that today!

I've tried to locate the wire harness connector at FCP and APW to no avail. Does this part go by another name. My thoughts are to splice the new connector on to an undeteriorated portion of the wires and see what happens!

Unfortunately, after driving the 20 miles for my original stall to within 300 yards of my home, she stalled again, would not restart and did not respond to the wiggle. As I consider my savings because of the recommendations you and Heat offered, I not that concern and believe I'm on track to fully resolving the issue. All in All, she's more than worth the $1600.00US invested!

Best Regards.

Spook, not sure if you saw this thread: (link to thread), it has more symptoms. Personally, I’m thinking fuel pump relay though the RPM sensor should also be replaced.



When my ’93 945T had a similar problem (stalling out) I just replaced both the fuel pump relay and the crank position sensor (also known as the “RPM sensor”), and the problem was fixed – never figured out which was at fault and I didn’t really care, the problem was gone.

Here’s the crank position sensor:



To find the crank position sensor, keep in mind that the piece on the left is bolted into the bell housing and the plug on the right will be connected to something else at the top, just under the air intake under your windshield wipers. Look for that connection and follow the black wire to the other end.

And here are links to them in the FAQ:

(link to discussion of the RPM sensor)

And just a quick tutorial on how to make links on this website:

[a href="http://www.brickboard.com/FAQ/700-900/EngineSensors.htm#Crank_Postition_Sensor"](link to discussion of the RPM sensor)[/a]

Change the brackets [ ] to < and > and you have the last link above. For the second picture, the HTML was:

[img src="http://www.brickboard.com/FAQ/700-900/Images-Parts/RPMSensor.gif"]

(again, replace brackets with < and > ).

And the thing about Volvos is that you (original poster) need to learn how to do most of the basic repairs (like the sensor / fuel relay) yourself. If you can do that it’ll be a good, cheap car. If you can’t, or don’t want to, it’ll nickel and dime you to death. For what it’s worth, the RPM Sensor and the fuel pump relay will both be in the neighborhood of $30 to $40 each for the parts. The RPM sensor is $29 here: (link to fcpgroton’s electrical page) plus shipping. Just call them about the fuel pump relay, should be around $35 or $40. Toss in some basic stuff like oil filters (Mann, a case of 10 runs $35 and don’t forget to pick up ten new crush washers), an air filter, new spark plug wires, etc and shipping won’t be that much per item.

Heat,

Many thanks and may the universe reciprocate!

In accord with my nature, reaching out to those who know more on a particular subject than I do has proven once again to be a wise decision. As you are aware, there is no shortage of folks who offer advise that has not been tested.

Spook's recommendation of wiggling the RPM sensor wire harness worked with just one wiggle. The crank positon sensor cable appears to be brand-new however upon closer inspection breaks in the harness wire insulation were observed. An after thought is that the battery tie-down on this car is missing, I'm wondering if shifting of the battery's position during turns or braking is putting unnecessary stress on the wires. I'll correct that today!

I've tried to locate the wire harness connector at FCP and APW to no avail. Does this part go by another name. My thoughts are to splice the new connector on to an undeteriorated portion of the wires and see what happens!

Unfortunately, after driving the 20 miles from my original stall to within 300 yards of my home, she stalled again, would not restart and did not respond to the wiggle. As I consider my savings because of the recommendations you and Spook offered, I'm not that concerned and believe I'm on track to fully resolving the issue. All in All, she's more than worth the $1600.00US invested!

Best Regards.

Dear Heat,

Good p.m. You could well be right, anent fuel pump relay.

Note: on the 1994 940 non-turbo cars, the fuel pump relay is a blue cube, on the first row of relays (that closest to the passenger seats), not a white rectangle, on the second row of relays.

I'm not sure which relay format - blue clube or white rectangle - was used in the 94 940 turbo. It would be a pity to have FCP send the wrong relay!!

Yours faithfully,

Spook