1992 4.3l Problem- Need Help To Diagnose

[BGALLO]

Hi,

My 92' S-10 truck with 4.3l throttle body is giving me trouble as of late, and I can't figure out what's going on. When I start it cold, it usually runs real rough, misses, hesitates and sometimes stalls. Once it warms up a bit it will run, but still has a miss to it and will hesitate or hit a flat spot or lurch when accelerating, especially under a load. Over the last week I changed; plugs, cap, rotor, fuel pump, fuel filter, and air filter. My computer is setting no codes either? Any help would be appreciated.

[maxwedge]

Scan it and look at the coolant temp sensor readings make sure thery correspond to air temp cold and warm up as the engine warms. Also check fuel pressure 10-13.

[jackass#1]

check timming, vacuum leaks, and maybe change out plug wires.

[rlith]

Sounds like typical CPI leaking... Pull your upper plenum and check for washing.

[crazycory1]

he has a tbi

[rlith]

Originally Posted by crazycory1

he has a tbi

Ahh ok... Have you checked to make sure the nozzles are spraying a nice cone and not dripping?

[bigd7315]

hey i have had the same prolem for 8 months and i have changed the coil , dist, wires ,plugs,fuel pump, fuel pressure reg, map sensor, fuel filter, esc unit, tps, idle air control motor, checked timing, replaced all vaccum lines, cleaned egr, cleaned injectors, and checked for other leaks with a vaccum gauge and i give up , changed all temp sensors and oil decending unit too so it is none of these on mine and i am still looking if i find the magic i will share

[jackass#1]

have you checked into your battery and charging system.

[bigd7315]

I have a new battery and alternator replace them when i bought the truck

[BGALLO]

Thanks for all the responses. It turned out to be my ignition coil and plug wires. I had just changed them a year ago as routine maintenance, so I figured they probably were ok. Must have been cheap parts?