Fuel Mileage after the Sulpher TSB

[Boaz]

DId anyone notice a improvement on fuel mileage after the Sulpher TSB was performed? I am picking my truck up today and I hope to see an improvement. Right now I am only getting about 16.5 MPG overall and I am 80%highway, 20% city driving.

 

[toybox]

If I were to make any guess (If there is an actual change in mpg) I would guess mpg would go down.

If Toyota originaly had the ecu at optimal conditions and was causing the sulphur smell, any tuning could only make it less than optimal.

I'm just following logic with this guess.

 

[Boaz]

bummer.........

 

[Duc Hunter]

I think the sulfer smell has more to do with what is in the CATs than the ECU. They probably changed the ECU so that, given how well the new CATs work, the emmisions at the tail pipe are the same. That could be better or worse, depending on the CATs. They may only be changing the cold start settings in the ECU to prevent fuel soak of the CATs, they could be only changing the accel pump functions......who knows. Let us know what you notice though!

 

[live4swell]

There was another post on the subjec a ways back, I had the Sulfur TSB done a ways back and have seen a MPG decrease as well as a slight performance decrease, others have stated the same thing, I will try and find the post and link it

 

[live4swell]

http://www.toyota-4runner.org/showt...&perpage=15&highlight=Sulfur TSB&pagenumber=1

I think that was it, it starts to get mentioned towards the end of the first page...

 

[HuntRunner]

I can't say I have noticed any change at all.....At first I thought I got better mileage, but I think that was just wishful thinking. I had this done back in June.

 

[sharp4runr]

I didn't see a change in performance or mileage bro.

 

[MicaBlue03]

Boaz, I wonder why your mileage is so low with that type of driving. 16.6 MPG is what I get (V6) with mostly city driving, and frequent short trips with several passengers. When my commute was 70% highway/rural road, I got 19-20 MPG. I generally drive with a light foot and am not contending with lots of hills, but still I don't get it.

I expect the TSB won't improve mileage, unfortunately. The speculation has been that the smell is sulfur compounds which are deposited on the catalyst during ordinary (fairly lean) operation, and burned off during heavy acceleration. The newer catalysts have mostly eliminated nickel from their construction, and that was what was reportedly used in the past to avoid sulfur buildup in the cats.

So presumably the TSB will change the catalysts to ones with a little more nickel and reprogram the injection so it's not quite so lean all the time.

I've only gotten the smell briefly and very infrequently, and never inside the cabin. There's a whole other discussion about keeping the smell out of the cabin, but I won't repeat that here.

 

[rando]

My observation regarding the Sulfer TSB fix was that my performance and MPG both went down. I'd have to go tally my gas receipts and mileage record (recorded on each receipt) to know for sure about the mileage.