Bryan Proctor

so heres the deal. im trying to get the old 1990 k1500 up and running. the truck had sat for about 3 months as it had an exhaust leak and would not pass emissions (and by "leak" i mean half the exhaust done rusted off the truck.) we replaced the exhaust, and started her up and the truck ran like a dream! got home and shut her off, came out the following morning to go get her inspected.. wont start. turns over and cranks, but wont fire. im thinking battery (obvious first choice.) so i checked the battery, it had a charge but was a little weak. had it tested, and it came back fine. charged it up... still no start. its getting plenty of fuel to the throttle body, and the gas is fresh. that leaves spark. replaced plugs, wires, cap/rotor and coil. tested it. now i have fuel and spark, still wont fire. what the heck am i missing??

any help you could give me would be appreciated. Truck is a 1990 k1500 silverado. 5.7L, manual trans.

oldchevy

You may be getting fuel, but are you getting the correct fuel pressure? Check that first.

Bryan Proctor

fuel pressure is good. its worth noting that the we dropped in a freshly rebuilt engine <12000 miles ago, so its seriously unlikely that the timing is bad. just replaced ignition module this morning also. im running out of ignition components to replace... im not one to throw parts at a problem, but my father and I, with over 30 years of combined automotive experience, are both completely stumped. this sh*t is only supposed to happen to fords! >:/

kevinkpk

Does this thing use a pickup coil, and module in the distributor?

Bryan Proctor

yes. both were replaced this morning. with the exeption of the distributor its self we have replaced the entire ignition system, i believe. unless i totally overlooked something.

kevinkpk

Crank it over without the cap, is the rotor turning? Also I had an 82 with that esc. I replaced the module, had it checked, said it was bad, replaced it, same thing. This time I had parts store test the new one, it was bad, turned out the guy doing the testing was frying these things. In my case the insulation on the pickup coil was bad, replaced that PITA, got it running.

Bryan Proctor

rotor is turning, or there wouldnt be spark to all the plug wires. at this point im convinced it has nothing to do with spark or fuel.

kevinkpk

what color is the spark, and is it in the correct firing order?

RacerX

if it doesnt fire, then you dont have fuel and spark. if you are sure you are getting spark then you have to double check and see if you are actually getting fuel. check the fuel pump relay to be sure it is closing and listen for the fuel pump whirl in the tank.

Bryan Proctor

checked each wire with a test light, all sparked. and sat in the engine bay and watched the fuel pour in to the throttle body. i know it has fuel and spark.