Computer flash and MPG

the long story is that I bought a 2k3 Prius for the better mileage compared to the wifes at that time new 2k4 Prius. When she first got the new Prius we were both shocked at the poor mileage compared to her 2k1 Prius, so took it back to the dealer and he said drive it for a while so we did but it was still the pitts. As you can see by my sig that even my best tank was better than her best tank. Her car has consistently made about 7.46Liter per hundred km. ,37.8 mpg Imperial, 31,5 mpg US gallon. So about 3 months ago we finally got the notice for the SSC40D (US TSB)/SABB-403-1A (Canadian TSB#) made an appt with the desk jockey at the dealer who informed us that they had done lots of them, so took the car in and they tried to flash the computers but the HV computer wouldn't take the flash and after conferring with Toyota decided that a replacement was in order. Installed about 3 days later and on we went. First thing noticeable is that the car went into S4 way earlier than before. When I say way I mean we were both shocked the first time we were about 9 blocks from home and the ICE stopped at the stop light. Both looked at each other and said "hmmmm what's with that". Now after two tanks of fuel and in the same type of operation as always. the mileage has improved to 5.77 Liter per hundred km., 48.9 mpg Imperial gallon, 40.76 US gallon. Now this might seem low but for the type of drive that she does with the car it's within spitting distance of what the 2k1 did on the same drive. The car is a very early build Prius, October 2k3 build date and the question is has anybody else noticed that their early build Prius has gotten a mileage boost with the SSC40D flash?

 

Dan the Canadian flash will be totally different from the US as the car is calibrated in Liter per Hundred Kilometer readout on the MFD, temp in C, distance in KM, speed can flop, but is different than US model. I think that is why it took Toyota about an extra 4 months after the SSC 40 D was released before the CDN version SABB 403 1A arrived at the dealers.

 

the SSC40D was the flash to make the car OBD11 compliant and this was an issue with the ICE computer and also to address some small issues with the operation of the Hybrid Vehicle computer which is the computer that was changed on her car. The OBD11 part has all the operating parameters, fuel consumption, speed, temps for the air intake, ambient, ICE, MG's and also throttle position and all associated error codes and their triggers. It wasn't just a CAN issue the early cars were not sent to NA with the OBD11 part of the programing there on the CAN. It was only available with the THHT. My question is/was has anyone noticed an increase in milege after the SSC40D flash on a early build 2k4, say between Oct 2k3 and Jan 2k4.

 

malfunction indicator light. Check engine light, what ever you want to call it.

 

thanks Liam, I was just wondering as the computer replacement has made a tremendous difference in the mileage. The origional HV (hybrid vehicle) computer wouldn't accept the flash and was replaced as a consequence.

 

thanks for the input Kyle, that was the only thing done to the car and like I initally said the MPG has risen by about 8 MPG. Also the car goes into S4 way sooner. I can only assume that the computer was the problem then. Thanks.