94 850 n/a intermittent stall, crank no start

[Dkherr]

Hey Everyone,

I’m new to the forum. I just recently purchased a 1994 Volvo 850 non turbo. It has 128,000 miles on it.

I don’t know too much about it’s mechanical history besides that the timing belt was done at 98k and the previous owner replaced the coolant temp sensor and thermostat.

I’ve had the car for about two months. I replaced the battery. It was shot. The car ran great up until a week ago. The car will randomly just shut off and then crank no start. If I wait an hour or so it will start back up again as if nothing happened. The idle seems to be ok.

I noticed the car still has the original 94 bougicord spark plug wires. I have no idea if anyone has ever done any maintenance on the vehicle.

Anyway, how should I proceed?

[Dkherr]

I forgot. There are no codes. I checked them yesterday.

[RickHaleParker]

It does sound like you may have a intermittence in the electrical system.
Do a thorough inspection of the electrical wiring. Damaged wires that maybe shorting out. Dirty, corroded or loose connectors that maybe opening.

[crlande]

My 94 did same thing, also with no codes, until the camshaft position sensor was replaced. It is a silver cylindrical disk just aft of the cap and rotor. Check for corrosion on the connector first. It may not be the issue but is simple to look at.

[abscate]

You will have to wait for the nonstart and then make a snap diagnsosis to get the right branch on then diagnostic tree.

I suggest starting fluid to check for fuel delivery problems. A pro would put a fuel pressure gauge on the rail and confirm correct pressure

If you want to throw parts, fuel pump relay and ignition switch electrical part would be the top candidates

Things it isn’t....bad gas, plugged fuel filter, bad oxygen sensor, bad catalytic converter, or bad ECU

[Dkherr]

I put a new fuel pump relay in and I’ve had no issues for three days. We will have to see if it happens again.