I've got a problem with my prelude. I bought it with a cel light and been trying to fix it. Its throwing two codes that come on after 1 1/2 days of erasing the codes with a obd2 scanner. The codes say system too lean and fuel trim problem. I've tried these things:
-Replaced damaged fuel line
-new fuel filter
-blox fuel pressure regulator
-clean o2 sensor
-clean fuel injectors

I've pulled the pluggs and o2 senor and they both have a white coating on them. The car stumbles and shakes when trying to accelerate between 1500-2000 rpms. I think a weak fuel pump may be the problem but I was wondering if anybody else has had this problem or any suggestions.thanks

 

have you tried the fuel pump yet? It is also possible that it is an O2 sensor that is broken.

 

I haven't replaced the pump yet. I'm thinking its next on my list. Tommorow I'm going to see If there is a vaccum leak anywhere.

 

also check for vacume leaks. Does the idle seem high? Even though its a map sensor system it might cause the CEL. Also on the top of my head check the EGR this might also cause a lean code but I would expect to see EGR code as well.

 

I know you've tried cleaning the injectors, but you might want to pull them out of the car and test them for proper flow. If I recall, they need 5v to open. Also, you might try a fuel pressure gauge on the fuel rail. This should tell you whether it's the injectors or not, or if it's something further back in the line (like the pump).