[GetCaughtDead]

I have a 91 DX with a 90 LS swap, and I've been getting a seemingly random code 43 - fuel supply system. What causes this? It used to only do it while cruising on the highway, and I could always just turn the car off and back on and it would be gone, but it's been doing it more and more, and now it has started doing it just tooling around town. Nothing really seems to be affected when it happens, it's just annoying for one thing, and also there's obviously something wrong to make it throw a code. but where should I look for the problem?

 

[SETI20]

That's the 02 sensor going bad.
It'll start to run rich...throw a code 2 as well, and than a CEL as it dies.

You'll need to replace it, or atleast check your connections.

 

[GetCaughtDead]

it actually was accompanied once by a code 1, O2 sensor. I guess that makes sense. I suppose it's probably all the oil I"m burning that would make the O2 sensor go bad? I changed it 2 1/2 or 3 years ago (the sensor, not the oil!), but this last engine I had put in is now burning a quart of oil in under 100 miles. :x I'll definitely check the connections first though.

 

[rex2nr]

sounds like an O2