I have a 88 blazer full size w/ 350 and throttle body. The truck sputters and misses under load but only after being driven for at least 5 - 10 minutes. It starts fine and always idles fine. Doesn't miss revving in park but will do it in drive and brake applied. There are no codes. Here's what I have done so far... Cap and rotor fuel filter Clean and gap plugs and inspect for damage. replaced one and one was quite oil-fouled. Replaced one plug wire that had got hot and swelled. checked for vacuum leaks Replaced muffler [no catalytic converter] Fixed pos battery cable that had contacted exhaust and was 1/2 eaten thru and shorting-- giving me an intermittent check engine light. That has stopped. Timing Checked EGR- idle decreases when pushed, moves when revved I have read other posts on this topic and fuel pressure test is recommended. I have a gauge but there is nowhere to hook it up on fuel injection. It only has the tank mounted fuel pump and the manual says you can't work on it or check it and need special tools. How can I get an idea if this is possibly the problem. I also still need to check for play in the dist. gear. I'm new here and if anyone has any advice it would be greatly appreciated. Thanks!