351w running rich?
 

After getting an oil change done, my mechanic said i think your running rich because he smelled a gas smell from the exhaust. I was in a rush and didnt have much time to talk more about it. What could be the problem here?

Perhaps your mechanic is trying to pad his wallet? Before getting too wrapped up from their comments why don't you check for codes. The PCM will tell you if it thinks the engine is running rich or lean or ???

I do have a check engine light on.... And i dont think hes trying to scam me cause i have smelled that gassy smell from the exhaust for quite a bit

Then you should check for codes to see what the PCM is trying to tell you. Ignoring it is not going to make it go away.

Pull vacuum line off regulator and see if it's leaking. That's where I always start first.

Better yet, check and see if your fuel tank is leaking. If you have dual tanks, the top of the rear one usually rots out from everything getting tossed on it from the tires. You'd definitely smell fuel that way. But check the codes, the computer will know what's up better than a mechanic who didn't check them.

Ya i went to autozone to see if they can read the code for me, but my computer is too old for them to read, they only read i believe vehicles 96 and newer, so im gonna have to take it to a mechanic for them to read it. Could it be a faulty O2 sensor? im noticing also a decrease in performance and especially mpg

That's odd. Usually parts stores carry obd1 and 2 readers since you can make money off of someone that needs a part. Go online and order an obd1 reader. They're very cheap

Look in this forum. You'll find a list of codes and how to check them on your EEC4 computer (obd1) with just a paper clip and a functional check engine light.

Yes i agree with untamnd i have a great code reader and it and its great just count the beeps/ blinks and look them up in the book it comes with and done.

Fuel Injection Technical Library » How To Run a Self-Test No code reader required.

Fuel Injection Technical Library » 2 Digit Self-test Codes 11-32 OBD-1 codes

Give this guy some rep points! Great post as always. I have to spread myself around before I give you any more points lol :-X22

You are too kind.....

Nothing special about my post, just pointing out the obvious and most overlooked item you should do when working on these trucks.