Firstfives.org

Its been a while since I posted.

I've been driving my car with seemingly no issues recently--

I have the wrong thermostat in and the car is running a little cool,

just below the first mark: ( *' ' ) .

Lately however I've been getting terrible gas mileage!!
I know I should be getting around double what I'm getting, the mileage has never been this bad.

I think I've narrowed it down to either a bad throttle body switch
(its the older style in the black housing)

Or a bad AFM. The mileage seems to be getting increasingly worse.

Anybody have any thoughts?

You can disconnect the TPS on the throttle body and it will run just fine, except maybe stalling coming up to a stop sign every once in a while. Easy check, but I doubt it's the problem. Could be AFM, but on a 530 the first thing I'd look at is the timing. Points wear and fairly quickly.

TPS,...Throttle Position Switch, right ? It's fun to guess all the acronyms. So many consonants, so few vowels. Pronouncing them is usually some variation of a raspberry noise.

I know from experience those TPS switches are really GFTH and BTHWYN.

Give up ? Good For Trailer Hitching and Blowing The Horn With Your Nose.

Besides that, if the car runs o.k. with them disconnected, what are they ? twinkie deals for more m.p.g.s ?

thank you very much for the response-------

I checked the timing and it seems on point.

As it happens, lately I've been noticing my car shake/vibrate a lot, even at low speeds.. I thought maybe I need a wheel balancing;

BUT THEN a few days ago on the highway one of my rear tires basically fell apart- exposed wire and everything. I put the spare on and no more shaking!

I'm thinking my faulty tire may have something to do with the bad mpg, but haven't been driving the car enough to tell yet.

I will get new tires soon and I will update when I find out whats going on!

If your car is running too cold, you may be stuck in warm up mode which is very rich. And that could explain your lousy mileage.

New thermostat did wonders for my economy.