I was getting a code 33. I replaced the MAF sensor and the code went away. However the car is sputtering still and backfiring through the intake. You can hear the pop in the air cleaner. I am not sure if it is electrical or a fuel issues. I am not familiar with the L98 fuel infection system. Ideas and comments appreciated.

 

Check the fuel pressure, and ignition timing. Start with the basics. If that doesn't help then you may need a scan tool that can read live data and see what data the ECM is getting from its sensors. Coolant temp, throttle position, MAF grams per second, etc. With computer controlled fuel injection you need to talk to the computer. It's also relatively common, if the computer is old, for them to fail due to circuit board cracks. The one in my 86 was dead when I got the car. Would run sometimes but not driveable and wouldn't communicate. I found the problem when tapping the ECM with my knuckle caused it to run better or stall, etc. New ECM and problem solved. So don't rule that out.

GD

 

I've already checked the timing I haven't checked the fuel pressure yet I'm fixing to do that here shortly which is most likely the problem with the car that's 30 years old I'm sure that fuel pump his toast by now ...

 

It definitely happens to a lot of people around here. Mine was toast but it sat for 11 years outside so the whole tank had to be replaced along with pickup and pump.... and injectors, ECM, and a variety of wiring problems fixed along the way to get to operable condition.

GD