1990 chevy truck obd codes

[leapyearharry]

i have a 1990 chevy truck with a 5.7 350 vin k. it will start when cold, but shut off. you can keep it running if you play with the throttle. i checked my obd1 codes according to the haynes manual. if using 1 flash then 2 quick flashes = 12, then it is showing 15 3 times, then 3 3times. the 15 = coolant sensor. what does the three fast flashes mean?

[admin]

Hi Harry,

Not sure what the three quick flashes mean, unless it's a code 33, but it sounds like you know what to look for, and this sequence is different. I would take care of the coolant temp sensor problem, clear the trouble codes, then drive the vehicle and see what happens.