hey, i own a 1970 cadillac sedan deville, that runs like a champ except for that it cuts out on the road. it shuts itself off, but not totally off, it almost sounds like a desiel pickup when it does this. the generator light on the dash comes on while its doing this (it was the oil light for alittle bit until it moved to the generator light). sometimes it backfires and is running good for a few minutes, or it will shut off altogether and you have to restart it. at first i thought it was a bad ground, so i replaced the battery ground cable, and put a ground strap from the altinator to the frame of the car. that still hasnt fixed it. now i'm thinking it might be the coil, but i'm not sure. any help would be greatly appreciated!
thanks

This doesnt sound electrical to me.... It sounds more like a stuck valve or something....

Does yours have the 8-6-4, im cant remember when that came out......

How is it when the car is cold, when you first drive it in the morning?

BTW, I'll move this into the engine section for you, because as Wes said, it doesn't sound like an electrical problem.

Nice choice in vehicle. My car does that when I turn it off, but that's because of the horrible carb tuning and maybe a little bit off of the timing.

Wes, the 864 came out in '81.

It might be the coil, .. I have no idea.

could even be the carb like a cut out of fuel or something. Try getting some carb cleaner. The fuel pumps are usually good, but the q-crap sucks it up.

I had a similar problem in my '77 Chevy. I was running a Mallory Unilite distributor in there which uses an electric eye to fire the plug. That problem drove me crazy for months until I figured out it was the electric eye that was shot. I replaced the distributor to a more conventional type of HEI that uses an ignition module.Never had the problem again. Your module can only be checked with special equipment( I believe) but that could be the problem. Either have it checked or price a new one and just replace it to be sure. A problem like yours can be so many things you'll just have to keep checking different things until you come up with it. Your "GEN" light and oil light will come on because the engine stopped and can't turn the belt to run the Alternator, so with no charge coming out of it the light comes on. It happens with a very loose belt also.Same with the oil light. No spinning engine to turn the oil pump, so it senses no oil pressure and warns you. Good luck...

thanks guys. i already put a new coil and new belts on it and they were tight so. i'll have to probably ugrade to HEI, better also. i'll try the carb cleaner also...thanks again.

At this point, i'd only upgrade to HEI if thats the setup you prefer. As far as ignition goes, check the points, condensor, cap and rotor. If they are adjusted properly and in good working order, you should be fine. When the generator light comes on, does it suddenly pop on, or does it flicker first and then come on solid. If it flickers, I would suspect something else causing the engine to stall, probably due to too low of an idle.

Didn't realize you had a points distributor in there, so my module theory is moot. We've upgraded a couple of points style ignitions to HEI with conversion kits. It's cheaper than a whole new distributor but the distributor should be in good working order.( no loose shaft or bad advances). I'm considering doing it to a '53 Dodge 230 flathead that we have in an M37 Powerwagon. We used the Crane system in a '70's MG and were very happy with the results.

hey, i just put a new rotor and cap in the distributor along with new spark plugs and spark plug wires about 3 weeks ago. the light comes on, it dont flicker or anything, sometimes it will pop and kick itself back to normal and it will work fire for a few minutes...just recently it has started to do it when it was just idling. before it would just do it going down the road.

You didn't mention if you changed those points AND condenser. Very important items, to say the least.

I'm thinking carb tuning or just build up of crap in the carb.

hey, i havnt changed the points or condensers yet...i had my boss look at them and he said they were fine, but i'm thinking they havent been changed for a couple years so i suppose its time to replace them. i'm goin to try that carb thing also, because it might just be cloged and restricting fuel, maybe.
thanks

This is probably not it, but check the fuel filter too. It's on the front of the quadracrap in the little hosing where the metal fuel line goes in.

It's a good idea to check out that fuel filter. If your boss knows the condition of a condenser by looking at it, then he is truely an amazing guy. :eek:

haha, ya i dunno if he looked at the condensor or not, he said the points were good, but i dunno.. would the fuel filter shut the car off, and start right back up after its ready?

It could. It's probably a good idea to replace it anyway. Replace the one on the front of the engine first. You can follow the fuel line from the carb down to it if you can't find it. This one is most likely to cause trouble, as the quadrajets have a bypass built in. It might be a good idea to replace the quadrajet one too while your at it.

With my '70 I only had one fuel filter. The fuel line came straight out of the fuel pump to the carb, then in the little housing where the fuel line connects to the carb is the filter. I just took mine out and put a clear fuel filter there that you can pick up at autozone/kragen/etc.

Theres SUPPOSED to be two. I was missing the one in the Quadrajet. (well there was part of it, but it sure didn't filter anything...)

my 78 sdv has the a similar problem it hesitates when i hit the gas and i have to feather the pedal to get it to stay running but sometimes it stalls altogether backfiring generator light oil light the whole 9 yards i have tried everything from tune up, k&n air filter, and new exaust to get it to breath a little better but nothing has helped so now i beleive it is the accelerator pump on the carb

I just got over a a bad dead spot from a standing start with my Edelbrock 600. Rebuilt the carb and put a new cup on the accelerator pump and now it works fine. Sounds like your pump is the problem to.