Running rich on driver's side only

[IDSkoT]

I've been getting really bad gas mileage in my sixxer... I'm talking in the single-digits. So, I took out all my spark plugs... and, well... I'm fvcking confused:



The spark plugs are in order of how I took them out. So the ones on the left is the passanger side, the ones on the right is the driver's side.




Obviously something is wrong. My question is: do I have to take it to a shop to fix it?


[P.S. This is a '98 V6 Mustang]



EDIT:: I also get random 'Check Engine Light' warnings. They come and go. It seems really arbitrary.

[jdawg]

O2 problem

[IDSkoT]

O2 problem

On only 1 side?

[jdawg]

you should have 3 or 4 O2's id one is stuck it could run one side lean

[IDSkoT]

you should have 3 or 4 O2's id one is stuck it could run one side lean

Oh


Any way to tell which one? Or no?

[jdawg]

usaully it will set your CEL but go to autostoned and see if there is a code. There should be 1 O2 sensor on each downpipe and 1 after your cat. Not posotive cause Im not a Ford tech. But get it checked sounds like an O2 problem to me.

[IDSkoT]

usaully it will set your CEL but go to autostoned and see if there is a code. There should be 1 O2 sensor on each downpipe and 1 after your cat. Not posotive cause Im not a Ford tech. But get it checked sounds like an O2 problem to me.

I've always heard those places will hook up to your car for free-- but, I don't even know how to begin to ask. Do I just walk up and ask if they'll scan my car for me?

[jdawg]

yea just ask them if they can sheck your codes. usaully whichever bank is rich/lean your O2 is malfunctioning on that side. I would but a factory O2 also.

[Ferendon]

If you've had the car more than a couple years, and you've never done them, then do them anyways. There's a way to test them, but it's not really worth it, if they're more than a couple years old. Also, be very gentle with the new ones. They have a porcelain element inside them, and if you drop them, it could very easily trash them. The Essex V6, had 3 O2 sensors, in most cases, 2 pre-cat, 1 post-cat. Cali cars have 2 pre, 2 post.

[brad148405]

similar issue, replaced O2 sensor and PCV valve, try those first.

[mlstrass]

Most auto parts stores will check codes for free, just ask. They provide that service, so they can sell you the parts you need to fix it...

[IDSkoT]

So I took my car to Advanced Autoparts today to run the codes.

I got P1151 and P0174
Aparently it's running lean, not rich?

Anyway... What do I replace? The guy at Advanced Autoparts said MAF and O2. But, according to these codes, only the O2 is bad? Any help?

[Zakerid]

MAF can be cleaned... o2's should be changed.

[IDSkoT]

MAF can be cleaned... o2's should be changed.

How can you clean them?

[Alpine CDA-9815]

Have someone scan for codes.