1991 Volvo Won't Start

I stopped the car after a normal trip. When I hit the brake all of the dashboard lights came on, including check engine. The car won’t start now. I checked the fuses, they’re OK. If I turn the ignition, the radio and other electric things work, so its not a battery problem. If I can’t get it going tomorrow morning, I’ll have to pay to have it towed.



Any ideas on what might have happened?

Do you know any Swedish prayers for the dead? You’ll need one.

There are two common things that will keep a '91 Volvo from running:

  1. Crank position sensor. Look between the engine and the firewall (may need a mirror) and see the lead that goes down to a probe that is attached to the top of the bell housing. If the insulation on that lead is frayed, that is almost certainly your problem. If it has not been replaced yet, it is WAY overdue and you are lucky you made it this far.
  2. Fuel pump relay. When you turn the key to the On position, can you hear the fuel pump turn on for a second to build pressure? If not, check the two fuses that power the two fuel pumps. I think they are fuses #4 and #6, but I am not certain about that. If the fuses look good, take a paperclip and short between them (one fuse to the other). If you hear the fuel pump turn on, hold that paper clip in place and see if the car starts. If it starts, you need a fuel pump relay, which costs about $40 and is right above the passenger’s feet, or you need an ignition control module. The ignition control module provides the ground for the fuel pressure regulator, and the part of the module that fails first is the transistor that performs that function. A rebuilt control module will cost you around $300 as I recall.

There are dozens of other possibilities, such as a broken timing belt if it has not been replaced every 50k miles as it should have been, but those other suspects are rare. 95% probability it is #1 or #2.

I re-read my own post. I said the control module provides a ground for the fuel pressure regulator. I meant to say the fuel pump relay. (Senior moment)

A battery can have enough energy left to power the lights, the radio, and some other accessories that draw low amounts of juice, but not have enough energy to be able to run the starter.

I would begin by trying to jump start the engine from a car with a good battery. If that allows you to start the engine, then you should have the charging system checked. If you are lucky, you might just need a new battery. Depending on the outcome of checking the charging system, you might also need to have the alternator replaced.

If a jump start doesn’t help, then you should begin to look further for problems such as a bad fuel pump.

Oops, I did not read the original post carefully. The mentions of radio and other electrical devices still working does imply that the car will not crank. I launched off in the wrong direction, assuming that it would crank but not start. Sorry.

If battery is too weak to crank the car, problem is most likely a bad battery or corroded connections. Be sure to check/clean the ground connection on the engine block.

If it turns out that the alternator is not charging on this car, 95% of the time it is because the brushes are worn out in the alternator. Brushes last about 150-200k miles. You can replace them with $5 and a soldering iron, but it is easier to replace the voltage regulator which comes with new brushes attached. The voltage regulator attaches to the back of the alternator with two screws. Easiest to access while the oil filter is removed.

I neglected to mention that I could hear the pump relay when I turned the key – I let it sit overnight nose down – my house is on a steep hill – low and behold it started up this morning. It sounds like its running rough and I can hear the engine react if I turn on lights or the AC. I let it run until it warmed up then turned it off and on a couple of times. It starts fine right now. I’ve been using Sheetz gas, mid grade, the manual for the car has up to 10% ethanol as OK – but I know the car should be run on high test. I wonder if you or anyone has had experience trying to run a volvo on midgrade w/ethanol. I’m alone right now and don’t feel confident doing much other than checking the fuses. The plan right now is to take it to the mechanic I’ve used for years and get him to check everything for connections, signs of wear and so on. I’ll ask him to take a look at the crank position sensor – Thanks so much.