I have a 88 rs tbi and I've been having issues with it falling on its face when trying to accelerate. If I give it a little gas it goes but if it's anything more than maybe quarter throttle it does nothing but fall on its face pretty much. Injectors are spraying, it's getting fuel. Idles fine and revs up amazing in park and neutral but the problem happens as soon as I put it in drive and try to go. Please help 🙏

 

What's your fuel pressure? You need to check it while under load and not just in park/neutral.

Bro suspected his FPR had issues and decided to rebuild it. Upon disassembly, the spring had broken in 3 places. Never checked fuel pressure but I was surprised it ran that way.

Additional fueling through AE and PE is triggered by changes in MAP and TPS, check TPS voltage is smooth and consistent from idle to WOT. Helpful if you have a scan tool or you can back probe with sewing needles and check with multimeter.

 

Yep. Fuel pressure under load, and scan tool to analyze the data stream--fuel trims, throttle position, MAP, coolant temp, etc.

As long as the scan tool is connected, verify EVERY sensor, and every computer output--EGR, AIR if applicable, spark advance, etc.

A weak coil can cause problems at heavy throttle. Will the coil fire a spark tester calibrated for HEI?

How old are the usual "tune-up" parts--cap, rotor, plug wires, plugs, PCV, fuel filter, etc.?