I drove across town to have an O2 bung welded in so I can use my Innovate wideband and tune my car in. Made the first half of the trip, about 40 miles, pull up to my buddies garage and shut the car off. less than 30 seconds later I refire it to pull into the garage and its hard starting, like the battery is going dead. I pull it in, get the bung welded in, and its hard starting again. Once it starts it runs fine. Start to head home on the freeway, about 10 miles away doing 75-80 and the car loses power. I push the gas and nothing, it doesnt go at all. After trying 3 times of trying to accelerate, I start to pull over and it dies. It wont refire even though it cranks, and chugs a little like it wants to start. I can smell fuel in the engine compartment. Volt gauge is reading approx. 10 at this time (first white mark above the red 8 volt mark on the gauge). To make matters worse its 105 degrees outside (car was running just above 220 mark when it died) and I have no A/C. I call a tow truck to get it the other 30 miles back to my house. No sooner do we roll it off the tow truck, but I crank it over and it fires right up with a cloud out the exhaust from being loaded up. Great, wasted $114 on a tow!! Signing up for towing thru my insurance tomorrow.
Pulled the battery right away and went and had it tested, and the parts store dude says its a little low and will charge it, to come back in an hour. I come back, he says its charged fine and the battery is ok. I have an underdrive pulley on both the crank and alternator, and I have noticed the volt gauge will fluctuate with RPM. I'm going to have the alternator tested tomorrow both with and without the underdrive pulley to make sure its ok and see what the charging difference is. It was also suggested that its my ignition module, and the high heat has finally killed it. I pulled the cap and it looks like the original module.

Will the low battery juice cause the car to die and not run?
What do you think about the ignition module being the cause of the fun time I had parked on the side of the freeway??
I can have the module tested at autozone, but they wont replicate the underhood temps.
I also thought about vapor lock, but I thought it doesnt happen to F.I. cars??

 

Can be a number of things.First off tho it sounds like either the timing is off or a worn out starter or both.Thats why its not turning fast when hot.First thing id attend too.Than if the car dies again it should crank fine and you can determine if its spark or fuel thats causing it not to restart and die.Could be an ign mod,than again could be a coil or weak fuel pump.Next time it dies pull a wire and check for spark or shoot some starting fluid or something flammable in the intake and see if she starts.once you know if its gas or spark you can look down the right path.

 

Ive had 2 ign modules fail on me and they checked out fine at the parts store so no real help there. This problem is tricky cause its symptoms can be related to many things. But I would bet its the module, your story sounds alot like what happened when my modules went out. Low voltage shouldnt make the car die, I had a crappy battery when my alternator died and the car ran fine for the 20 miles it took to get home.

 

well a bad battery or alternator would cause mod to fail.In other words a weak ignition/charging system stresses the mod and will burn it up.

 

Yeah, the starting issue sounds like a bad ground, or bad connection. A bad ground (almost imperceptible) on my car caused the car to be hard to turn over, as if a dead battery, and once in a while, the tach would flutter and go nuts.

Your MAF (or MAP) almost sounds like the culprit for the problem while driving. My MAP became disconnected while driving on the freeway once. The car would run and drive fine at that speed, that throttle position (+/-5%), but if you tried to go above that range, it would sputter/want to die. It appears that whatever VE block the ECU is in when the primary sensor (MAF or MAP) disconnects/dies, is the only VE table it will run in at that specific time (until you restart the car, or fix the issue). I was able to run my car the last 15 miles back to my exit, and fix it once in a safer location (it died when the car came to a stop).