75 supreme dies when warm

[7MiMi7]

I just bought an old 1975 cutlass supreme for $300. The problem is it starts very hard(sometimes not at all) and it dies when it warms up to normal operating temperature. I tried to start it this morning, and it took 15 minutes to get it to turn over(we've had a cold snap the past few nights). Once I got to the light up the street, it died and would start again.

[xeroinfinity]

Check when it doesnt start for spark,
then test the coil pack inside/under the distributor if you have no spark.

The wires sometimes break and cause this off on thing.
Usualy not repairable, pretty inexpensive from a auto parts outlet.

[rosswade]

If you just bouht the car you will most likely need a quick tune-up. Without question change the cap, rotor and fuel filter. Change your oil as it is probably contaminated with gas (causing poor cylinder sealing). Recharge your battery overnight with a buddy's charger. Also make sure the plugs are not from the stone age and that the wires are not sitting on the manifolds. If all fails, then try swapping heat-sensitive parts like the fuel pump and ignition module under the cap. These are cheap and worthwhile to change in old cars if you don't know when they were last changed. Then check for vaccum leaks around the carb (propane bottle) and check for a faulty EGR. If there is a serious mixture problem a quick temporary fix is to wire shut the choke halfway or a little more - and adjust the high idle cam if needed. Buy youself a Chilton Manual on eBay for 10$ - lots of flow charts and will save you $$$ on garages and towing.

I had a 77 Supreme - no floor, but I loved it...

If you are allowed, scrap all the useless emissions stuff if it hasn't already been done to eliminate more variables.