This post shall sound a bit strange however please bear with me as I'd appreciate some advice.

I purchased an OBD reader and install an app called 'Torque' on my smart phone. I monitored the readings for a few weeks and it suggested the bhp and torque were pretty much as per an unmodified model with a slight variation (164 hp and 259 ft lbs torque at the wheels), no big surprise. I had an ECU remap in August and the rolling road showed 202 bhp and 323 ft / lbs torque at the wheels, reasonably impressive gains. The bhp and torque readings on the app were reasonably close to the rolling road readings when I drove in a spirited manner and it felt like there was a considerable benefit from the remap.

In November the car was left stationary for a couple of weeks and the battery died. A new battery was fitted and I've driven around 400 miles since.

Here's the strange part; since the new battery has been installed the bhp and torque readings don't get anywhere near the previous readings, they are more inline with the unmodified readings. I would have thought an ECU remap would be permanent however the readings on the app suggest otherwise. At the same time the weather temperature has plunged from around 12 degrees to freezing.

Any idea what could be happening?

 

Was the ECU remap done by a performance specialist?

When the ECU is remapped it is permanent until the next remap.

 

Hi Jackra,

Thanks for the prompt response. The ECU remap was performed by a specialist, I think they were an affiliate of celtic tuning as celtic tuning is mentioned on the invoice.

It just seems to be a strange coincidence that the power is down when the battery was changed and when the weather has turned cold.

 

It is strange.

Also performance is usually better in cold weather, all else being equal, because of denser air being "breathed" in. Especially so with super charged engines.

Seat of the pants judgments are difficult unless there is an outlandish difference.

I have just done an ECU tune on my non supercharged Range Rover and am trying to judge whether or not the performance is better!

 

Wow! People spend lots of money to modified the engine with turbo and super charge to gain just as much power, but you just spend a little money to remap the ECU and gain that much power. Very impressive.

 

Btw the ECU remap from Velocityap on my RR I do believe has increased the HP and driveability and even given better mpg.

The device they "give" you to do the remap keeps copies of all programs including the original and tweaked versions. All of which can also be stored on your home computer.

So one can go back to the original or any tweaked versions that you want.

 

The Torque app isn’t the best to judge power unless you’ve setup all the setting to display correctly. Meaning if you updated the app and it changes the default setting..you’ll gain/lose power because you viewed the before numbers with the “then” default settings.

when you had the battery changed, was this at the dealer? If so, they could have updated your ecu with a open campaign/recall. That would mean your tuned file is long gone.