1999 Chevy k2500 5.7 vortec



In the last month it’s got a misfire when it’s idling in gear, also does it when under a load like going up a hill. It runs decent when driving down the highway. When it’s in drive and idling at a stoplight it also has a surging idle. When it’s up to temp and in reverse it chugs and will die. The idle is steady when it’s in park but still misfires. It runs a lot better when it’s cold/first start of the day and the issues get worse the longer it runs. Temp gauge is staying consistent to its normal range. No check engine light/codes.



In the last year and a half I have replaced the plugs/wires/cap/rotor, distributor, TPS, IAC sensor, O2 sensors, fuel pump/filter/relay, throttle body, etc. Most recently I did the coil and ignition control module, no change.



I’m wondering about the fuel injectors, I’ve heard the spiders are a common failure point. No idea if it’s ever been replaced but I know for sure it hasn’t in the last 12 years I’ve had the truck. Just looking to get some advice on what I could do. I’ve had a lot of weird issues with this truck surrounding the idle in the past.

thank you