I bought this 93 Del Sol S last week, and it started acting up on me on the drive home after I had paid.

The original owner had left it parked for over 2 months because of a move. He had changed the oil in early February, and based on the mileage on the window sticker, it hadn't been driven since. The engine has been flashing the check engine light with code 43, which is a fuel supply system problem. It bogs down really bad if I try to accelerate, and I have to step on the clutch for a moment so it can recover.

I originally thought it was just a bad gas problem because it had been parked, so I have drove through 2 tanks of gas with gas drier and injector cleaner with no luck. I have also changed the fuel filter. When I called the original owner, first of all he claimed the car had never done this before, that the spark plugs, distributor cap and o2 sensor are new (so he could pass emissions).

I got a fuel pressure gauge at the advice of others, and the gauge shows 33psi at idle, and 43 psi at idle with the vacuum line disconnected from the FPR. I believe that means my fuel pump is ok?

I have no idea where to go from here, and any help is greatly needed. Thanks.

 

I saw a LOT of code 43 threads stemming from o2 sensor problems here on H-T. Since I have a brand new Denso in hand, I guess it's worth a shot. Besides, the owner may have put a Bosche in, so why not try this out.

I just took out the currently installed sensor, and it's covered in black char. Looks like this may have been at least part of my problem, but I want to make sure I'm getting to the root cause. If the o2 sensor is all blackened, something else must have caused that in the first place, right? Anything I should do before actually installing the new o2 sensor?

 

an O2 will naturally get "blackened" due to being in the exhaust flow. But it shouldn't have things caked on it. (sign of being too rich)

90% of the time 43 is the O2 sensor or a connection to it.
Swap it out and see where it takes you.