I drive a 88’ Volvo Wagon 760 turbo and it has about 315,000 miles on it. This car has been in my family since it was brand new and it has never had any issues until now.

So I was driving from Rolla to St. Louis today which is about a 100 mile roadtrip and about 60 miles into the trip, the car started rocking back and forth a bit and it felt like it was bumping and sputtering as if it was running out of gas (I actually don’t know what a car sounds or feels like when it runs out of gas so this might be a bad description). This is while I was on the highway. I assumed it was out of gas (the fuel gauge doesn’t work so I base it off how many miles I’ve driven) but I had only driven 150 miles since I last got gas so that didn’t really make sense. After about a mile of the car sputtering, pushing on the gas did nothing so i coasted until I got to an off ramp and I stopped and turned off the engine. I tried turning it back on again and it took me about 3-4 tries before it actually turned on. Then I tried revving the engine a little and nothing happened. So after the car cooled down a bit (like 40 minutes later), the car started working again. There’s plenty of transmission fluid and it’s not leaking, the throttle isn’t detached, there isn’t a coolant leak, and there was plenty of gas. I did have a used igniter module in the car so I replaced that with a new one that I had (assuming that was the problem), made it all the way to St. Louis (about another 40 miles) and it broke down again. So for whatever reason the car can’t survive long trips and it works perfectly fine once the car cools down.

Something must be overheating. Any ideas? Electronics maybe?