1987 Chevrolet S-10 Pickup1987 chevy s10 2.5l tbi will not start. changed bad fuel pump works well now strong pressure to throttle body. change fuel pressure switch, oil pressure switch, o2 sensor, map sensor, distrib cap, rotor, electric part on dustrib, check for 12v to fuel injector good, check ground good, fuses good, ecm swapped changed fuel injector engine runs now but runs high idle and will not wind down. when i step on gas engine bogs down

SKM, fuel pressure regulator is on top of throttle body. This could be the problem, could also be vacuum leak, faulty EGR, etc. You may want a good Tech, to diagnose and estimate repair. Check the attached links,instruction and guides, Good luck
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Pumping a fuel injected car has no effect on the starting process. This sounds like the fuel pressure is low or the injectors are having problems. The injectors could be having trouble from sensors that tell them when to open.

Check all fuel lines for leaks, make sure it doesn't have bad gas in it. Listen for fuel pump when key is turned on. Change fuel filter. See if that's helps.

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leaky injector/s is flooding motor, mechanically clean or replace. And clean throttle body while you are at it with spray cleaner. Should be almost spotless where large throttle valve opens and closes.

I had the same problem with my old 1987 Chevy blazer s10. The problem was the ground wire of the fuel tank was rusty and it broke. So simple was the problem. But before that, I checked and change the fuses, the fuel filter, the oil pressure switch (this is related to the fuel pump to) and finely when a was ganging the fuel pump saw that the ground wire was broken or damage.

I hope this can help you.

relace the throtle air idle valve.The temp switch will allso cause this problem.

you have to reset base idle see manual at library for procedure

That eliminates the crankshaft and camshaft position sensors. Have you checked the fuel injector itself for an open winding or stuck valve plunger? There should not be a steady 12 volts to the injector--if good injector, it would be spraying fuel steadily into the throttle body. But at least the engine should try to run if poorly. Take the injector out, dry it off with air, and intermittently apply 12 volts to one terminal while grounding the other. You should hear a click from inside every time you touch 12 volts. If not, replace it. If it does, it may be plugged with debris. Try blowing through it in reverse with compressed air.

Check the injector for 12v on one wire. if good check the other wire for a ground witth the key on. The ground wire pulses from the ECM If you dont have 12v from one wire to the other but you have 12v from one wire to battery ground then be sure the ground wire is good to the computer. If you don't have 12 v at any time check for open hot wire or bad fuse. ADD 12v to the hot wire at the injector. DO NOT add to the wrong wire or you will fry the computer

fuel pressure isnt right.. need to get a fuel pressure regulator so you can regulate the gas flow..