Hi All,

I bought my 2000 S70 GLT SE about 4 months ago. When I first had it (the first week or two) it was getting 23-24 mpg. Then the Check Engine light lit up and the code shows a bad catalytic converter. Since then my mpg has gone down to a pretty consistent 20.9 mpg.

I drive mostly city, a little highway... probably a 60/40 ratio.

I recently read that the fuel jets going bad bring up the same code and that got me wondering if perhaps the cat is fine, but the jets are messed up... Any thoughts?

I think that two weeks of driving didn't really give me enough of a baseline, so I've been unsure of what to hit first in terms of improving my gas mileage, but this 20.9 mpg is worse than the truck I sold to buy this S70! It can't be what I'm stuck with mpg-wise.

Thanks, and I'll take my answer off the air. haha. I'll leave the NPR jokes aside from now on.

 

What does "take my answers off the air" mean?

If you have a problem and it's effecting your gas mileage, I guess you should fix the car. If you are asking if I think your injectors are bad or catty, I have no way of knowing. You can try running some fuel injector cleaner in there but if you have a catty code, I'd have a professional or two check it out and go from there.

 

"Take my answer off the air" is just me being a smart aleck. I hear callers to radio shows say it all the time. Just trying to be friendly.

I'm getting the car fixed, I'm not asking for anyone to diagnose the car online. My question is, given that the same code comes up for injectors AND cat, which the code is referring to? And is it possible that the dip in mpg is an indicator that might lean one in the direction of the injectors being the problem?

thanks

 

Exactly what OBD2 code was set? That might give us a clue..

 

gdog, good question. I just know that the mech that I took it to told me it was a bad cat code. It IS intermittent, (it's not on now) coming on and going for, each for days at a time.

Next time it lights up I'll get the code and post that.

Thanks.

 

If the code has come and gone, it is likely still in the computer. Have it read and let us know. I have never heard of an invector code but then again I don't know much.

I don't mind repeating questions so, do you use fuel injector cleaner?

If you think you have an injector running lean get it fixed asap. Running lean is known to burn valves. Major work.

 

I'll get it read asap. I have no idea if there is an injector running lean or not... How would I know?

 

I believe bad fuel injectors can cause the car/cylinder to run lean. Run some fuel injector cleaner in the tank next fill up. I usually use Lucas.

More than likely you will have preformance issues. Like missing or not doing good at certain RPM's. I hear people complaining about their cars hesitating at certain RPM's while WOT and stuff like that. I'm just guessing, you may want to ask a real mechanic or do a search.

I have read a lot about burnt valves and how running lean is a cause.

 

Thanks! I'm not noticing anything other than awful gas mileage. Is 21.1 mpg atypical?

 

Yes, around town.