My tC doesn't currently have a S/C installed on it. When I called Scion before they asked me if it still had the S/C on it. I believe the person I bought it from had one before they sold it too me but took it off.

My question though, if they never got it re-tuned for the stock setup would that cause me to have a funny idle, a lot of oil consumption, and pretty bad gas mileage? My idle seems to go up and down constantly, from about 600 RPM - just over 1000. It goes up then falls, then up, then falls. I'm getting around 24 mpg mostly highway driving.

Between oil changes I have to add quarts of oil just to keep it at a decent level.

One other note, I just rebuilt the engine as I had low compression in Cylinder 3. I believe that everything is running fine as far as that goes.

Thanks guys.

 

The low compression might be the main problem because that will not be affected by the s/c tune. If the car was tuned for the supercharger, you'll need to get another ECU without the s/c tune on it. You can find them easily online like ebay (I did this) and swap it in and program the engine immobilzer to start the car again.

 

Appreciate the quick response. I don't think it has low compression anymore as I rebuilt the eninge (haven't been able to check it). I did put in Wiseco forged pistons though so the compression is different all together. If I do pick up a new ECU without the tune how do I program the immobilizer?

 

Wat yr is your car an if you get another ecu would you sell the one with the trd tune

 

Well, I'm not sure that it has the S/C tune on it. I need to call Scion to see if this ECU has the S/C tune on it still. If it does though I would be willing too.

 

I don't think Scion will know, it isn't like they maintain a database. the S/C tune is a reflash for the 05-06 models (the kit came with a module to do it) and for the 07-2010, it would be reflashed by a dealership computer. You should contact the dealership and see if they can read the ECU and find out.

Also, oil consumption isn't from the s/c tune. That is just poor engine condition.

 

I don't know how it could be poor engine condition. It was just rebuilt. But alright, thanks.

 

Your oil has to be going somewhere. It is either leaking out somewhere, or it is blowing by in the cylinders and being burnt up and sent out the exhaust (blue smoke).

 

I don't have any signs of a visible leak anywhere. No oil on the ground or anything at all. And it doesn't seem like it's burning through the exhaust. I get "smoke" sometimes while driving but it's like 10 degrees out now so that's pretty regular.

 

after driving the car, (maybe after doing a few hard pulls) pull over and inspect the vehicle, look for damp spots around the engine where oil could be leaking out, or look for black carbon deposits where the oil is leaking out, and then burning off from the engine heat.

 

Hmm. Alright. I'll have to try that. One other thing, I didn't get the valves done. Just had the head checked and surfaced. Could the valves be a problem?

 

Yes, blowby through the PCV valve.

 

I replaced the PCV valve awhile ago and it didn't seem to change anything. Can I do a valve job myself or will it have to be brought somewhere? Any idea what it would cost?