Electrical

I have a 1995 Olds Aurora with 115,000. My question is , at any speed 20-65+ I will be driving along and the engine will shut off by it’s self, and then i would coast to the side of the road. I then would put the car into park wait a few minutes and start the car up.This does not happen all the time but enough to not trust the car. I would start replacing things (ignition switch, but at $250.00,and if thats not the answer,more money)Any ideas.

Well the best thing I can think to spend your money on is a repair manual for the car that has a good wiring diagram. Factory manuals are the best. You can download service data from Alldata.com for a small fee. Money well spent in my opinion. Using the guide and something like a test light probe you will be able to check things like the ignition switch and verify where voltage isn’t getting to, saving you money over needless parts replacement.

The ignition switch is a very likely suspect here but it also could be a faulty fuel pump relay or bad wire connection somewhere. I would try to verify the ignition system is working when this trouble happens. You could also try spraying some starter fluid into the intake to see if the engine trys to start then. If that works then something in the fuel delivery system is the problem.

Well yeah I have plenty of ideas,but I want you to do a underhood visual inspection first (paying close attention to the battery and battery related connections) post back your report along with maintiance history and your technical abilities.

What are you going to do in regards to the suggested repair manual advice?

How good are you at determining if your problem is fuel or ignition?

I’m over 60 now, and i gave up on doing most of my repairs about the time everything went electronic. The trouble is when this happens the car will start up almost immediately upon stopping,waiting a bit and turning the ignition on again. It was just this last time that it wouldn,t i had it towed to a mechanic i’ve used for years, It started right up for him, he put it on a computer to find any thing on the auto computer, it showed nothing. luckily the battery is under the back seat so the compartment is clean and easy accesable I’ll check grounds and and connections again and get a wiring diagram and go from there. Thanks guys.

I’m over 60 now, and i gave up on doing most of my repairs about the time everything went electronic. The trouble is when this happens the car will start up almost immediately upon stopping,waiting a bit and turning the ignition on again. It was just this last time that it wouldn,t i had it towed to a mechanic i’ve used for years, It started right up for him, he put it on a computer to find any thing on the auto computer, it showed nothing. luckily the battery is under the back seat so the compartment is clean and easy accesable I’ll check grounds and and connections again and get a wiring diagram and go from there. Thanks guys.

Don’t be discouraged by the more modern designs. Using a good logical trouble shooting method will take you far in fixing this trouble. Problems like this are usually simple ignition switch, faulty relay, or wire connection problems that seldom can be found using computer printouts.

One thing you might want to try is tieing a small test light to suspected 12 volt points to have a visual signal when the trouble happens. You could use small 12 volt lights or even LEDs to do this. A common LED with about a 1200 ohm, 1/4 watt resistor in series with one of the leads will work. Using the wiring guide to help locate the areas you want to test before hand will help show you where to tie to. With long enough leads you could tape the lights to the dash for quick and easy viewing. I am pretty sure you will find this is a simple power connection problem. Either with the ignition switch, a relay, or wire connection under the dash or the hood area.

Anywhere the wire connects to the battery, to another wire, to a switch, or to another component is a possible place for an intermittent disconnect, resulting in an intermittent stall or no-start.
The battery connections are always high on the suspect list. I just had an 11 year old truck with an intermittent stall and no-starts. I did the usual volts and ohm checks. Found nothing amiss.

The next day, the truck wouldn’t start. A check with the multimeter found the voltage low from the battery cable terminal, where it had measured good voltage before. What the??!! Long story, short, the voltage from the battery post to the cable terminal was sometimes good, sometimes not. I filed the inside of the (positive) battery terminal until it was nice and shiny, swabbed the battery posts and inside the terminal loops with petroleum jelly, re-connected the cables, and all was sweetness and light. This could be your problem. Could be.
Disconnect the battery cables, file and sand (or wire brush) the surfaces which contact each other on the battery post and cable terminals, apply petroleum jelly, re-connect.