My 94 gsr had been throwing up a CEL every morning and its code 43, fuel supply system. It runs very rich, plugs are BLACK! and the gas mileage it aroung 200 to a tank. Pretty bad. Other wise it runs good. Anyone know whats wrong? Thanks in advace, Chris

 

Oh also the CEL only comes on when the car is started up from cold. When the car is warm the CEL will never come on. Normally i see the CEL, flick the key off the on and it doesnt come back on.

 

if I remember, things to check for cel 43 are main relay, fuel pump, injectors, injector wiring, EGR (if u have it), fuel filter, air filter. Pretty much the main things that have to do with the fuel delivery system of the car. OO i forgot, o2 sensor too, alot of the time I hear it's the o2 sensor, might wanna check that one out first.

 

Checked the fuel pressure on the return side and there was no pressure at all. I couldnt test the fuel pressure on the other side because i didnt have the fitting. But having no pressure on the return side means what? Bad fuel pressure regulator?

 

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There's a line going from the FPR to a line on the frame that goes back to the gas tank. Make sure that's on right and not leaking.

 

my gsr does the exact same thing

 

Thats where i tested for pressure and there is none. Also no leaks.

 

Can the o2 not be readin properly but not throw a code?

 

....

 

possibly the air filter/fuel filter. its probobly dirty so its pushing for air/fuel to go through. maybe even injectors.

 

uhhhh, have you tried a new FPR?

EDIT: Wait, did you rev it up while the line as off? How exactly did you test the return line?

 

I had this problem a couple months ago, and it was a clogged cat, which among other things, was ******* with my o2 readings, giving me a code 43.

 

Ill try a new fuel filter first, cant hurt to change it.

 

uhhhh, have you tried a new FPR?

EDIT: Wait, did you rev it up while the line as off? How exactly did you test the return line?

uhhhh, have you tried a new FPR?

EDIT: Wait, did you rev it up while the line as off? How exactly did you test the return line?

uhhhh, have you tried a new FPR?

EDIT: Wait, did you rev it up while the line as off? How exactly did you test the return line?

uhhhh, have you tried a new FPR?

EDIT: Wait, did you rev it up while the line as off? How exactly did you test the return line?

 

No when the line was off not a lot of gas was running back to the tank, no psi reading was shown so it was below 0 and i did not rev it up while i was goin this.

 

^^Don't worry about that. That's normal. How many miles do you have?

There's so much misinformation in this thread it's not even funny.

If you have a ton of miles, and a stock cat, my guess is that you have a clogged cat, and some expletiveed up o2 sensor readings. I would take your cat off, and see if it's clogged. Hold it up to a light and look through it. It needs to look like a screen door with no clogged holes.

 

The return line wont be pressurized....it returns fuel to the gas tank, thus the "other end" of that return line is vented into the gas tank, which isnt pressurized like the fuel rail. I suppose the first questions people should ask is, what mods do you have? VAFC, chipped ECU, adjustable FPR???

 

No mods other then an intake, header, and 2 1/4 exhaust to a stock muffler. 156xxx on the motor though. Do not think the cat is clogged becuase i had it off when i did the exhaust and i think i remember looking through it. Also when i drive around normally there is no smoke but if i get on it as soon as 6k hits enough black smoke comes out to disappear the road behind me. Well not exatly that much smoke but A LOT! This only happens when i drive the car normaly for a long time then redline it. But say i redline 1st,2nd,3rd then right after that get on it again no smoke will come out, onlt the first time i beat on it after driving normally for a while.

 

Just changed the fuel filter. Ill see if the CEL still comes on tomorrow morning.

 

I've got a 95 gsr. Mine has been doing the same thing, never pulled the code. It would have a CEL when starting from cold that would stay on until the car was shut off. But if I turned the car on 1 min later the CEL would be gone. I replaced my header last week and decided to replaced my O2 sensor while I was down there. And wouldn't you know it no CEL since *knock on wood.

 

Yeh CEL came back on so ill try o2

 

Any idea where i can get another o2 sensor for cheap. Advanced auto told me i think 175 and i was like holy ****. A universal one is like 30 bux but should i use that.

 

I've had no problems on my bosch universal from autozone. Its a little gimp with having to cut your plug off and wire it up, but it works like a charm. I'd most likely bid on that OEM one on ebay though....

http://cgi.ebay.com/ebaymotors...ZWDVW

http://cgi.ebay.com/ebaymotors...ZWDVW

 

My b20 does that. I get about 260 to a tank.