1994 940 Volvo Turbo (130,000 miles)
Engine stalls at 20 mph, and at stop. Lose all power/all red lights come on dash. Immediately restarts. Dealer mechanic checked and said runs fine, no codes came up. Has had fuel/fuel pump issues in past, and recently replaced hose between radiator reservoir and radiator. Any help would be appreciated.

i had the same problem. it was the battery cable connections. clean and tighten them. when you hit the brakes, the battery shifts, and causes the power failure. battery reseats and it starts.

I have a 1993 Turbo. My experience is that it got to do with 1 of the 2 things. Either it is the fuel pump relay or the power stage. The most likely cause is the faulty fuel pump relay. It is cheap like maybe $25. Then go for the power stage replacement. Check your records whether these two items had been replaced considering the car is 11 years of age. power stage is about $70 or less. Do let me know the outcome.

Definitely sounds like 1 of three things:

1. Failing fuel injector relay
2. Failing ignition power stage amplifier
3. Failing engine RPM sensor

All three easy DIY repairs. I would start with by replacing the relay and try the others especially if it usually happens with a hot engine. Check out the FAQ's on the three items above.

Good luck,


Mike