Problem starting car

ncrowe

We own a 1995 Volvo 940 with 86,000 miles. During this summer, on several occasions, the car hasn't started after sitting in the hot sun for the day. The next morning (when it's cooler) the car starts. The engine sounds and we can smell the gas when we try and start it, but our mechanic says he can not fix it unless the problem of not starting happens while it's at the shop. I've tried to have it towed to the garage, but each time the car starts before the mechanic can look at it. He's checked everything out while its running and says its all in working order. Does this sound like an electrical problem? Or (sounds unlikely, but) something related to the heat? Any ideas?

Mr_Shiftright

It does sound electrical as modern cars rarely if ever vapor lock anymore. I'd say some ignition component was dying a slow death. Your mechanic really is right, though. He can't diagnose a problem that isn't there. All he can do is guess at your expense if you want him to do that. Sometimes out of frustration that's what you have to do.

One trick I've learned is to ask the parts counterman if he sells a lot of ignition parts and if so which one?

majemalyn

I hadn't driven the car in about 2 days. When I tried to start it, nothing happened. No lights came on or anything so I assumed it was the battery. I put in a new battery the same way I took the old one out but it still does the same thing - nothing. I am a female single parent with 2 young kids, the youngest is 1 month old, so I can't push the car to let it roll and jump start it that way (manual trans). The starter was replaced about April/May of this year. Any suggestions?

cutehumor

since the car is 11 yrs old, make sure your battery terminals aren't corroded. if they are, you need to scrape it off the terminals and use dielectric grease on the terminals to prevent the corrosion from coming back

I have a 92 mits mirage..last year I let the car sit for four days during 4th of july. car wouldn't crank or anything, it was corrosion on the connectors.

majemalyn

Thank you, cutehumor. After I cleaned the cables, the lights come on, horn blows, etc. but when I turn the key, there's just a buzzing noise, no clicking or anything, just some kind of buzzing. And still won't start...H E L P!!!!

cutehumor

I would wait at least 1-2 hours after cleaning the terminals of corrosion before starting so the alternator can get power from the battery. since the car didn't have any power at all for two days. It's a good sign that you got lights on. does the car turn over at all?

majemalyn

It wasn't turning over or anything but I tapped the cables down a little more and the car started afterwards. Sorry for my naiveness but it's a learning experience for me. Thank you very much for your help!!!

cutehumor

It looked like your problem was that the terminal connectors were corroded. After the cleaning, the connectors were not on the battery terminals all the way that's why the lights worked, horn, but not enough power to crank. I'm glad the problem is solved. Now make sure the battery terminal connectors are screwed on tight so they aren't jarred loose while driving. Usually there is a locknut screw that secures the battery connectors onto the battery terminals.

bored

Could be a bad Crankshaft Position Sensor.

cute... Mitsu Mirage battery terminals love to corrode. This has happened on my sister's '93 Plymouth Colt on several occasions, causing nothing to work, or the car to start. Right now, they're corroded again, and are about to get cleaned.

tntchaf

Have your mechanic check out the "impulse sensor" at the back of the engine. I had a similar problem with a 940 that would not start when hot, that was cured by replacing the impulse sensor. It reads flywheel revolutions and triggers the ignition. The cost is $53-63 and Chilton's Flat Rate Manual says time involved is one half hour.
Had an unfortunate experience with the repair at Jaffarian Volvo in Haverhill, MA. They claimed the repair took 4 hours and overcharged by 3-1/2 hours times a hefty labor rate. Be interested to hear how you make out.