Tune makes car overfuel?

[mps_za]

Hi can i please get your help and opinion...

I had a run on the dyno on stock tune and the graph was produced that looked very good exactly as it should, and the car was running a bit rich as it should.

then i had some tunes loaded, but in both cases the car was overfueling and running as rich and richer as stock.
There was an initial torque increase but, killed the power at the top to about the same or even less than stock.

BOTH these tunes were running fine on plenty of other cars. The one was a little better than the other though.

Im back to the stock tune, everything is fine again. How is this possible?

 

[Sport6]

Off the shelf maps do not work 100% for every car. Your fuel pump might be a bit stronger than others, or you have fuel trims that your car is saying are a bit lean (like +10%) and is dumping in extra fuel.

Each car has its minor differences and a tune that was developed and tuned on one car could work on other cars and might not work at all on others.

What are you using to monitor your car (like Knock Retard, Fuel Trims, Boost, Fuel Pressure, etc.)?

 

[mps_za]

What are you using to monitor your car (like Knock Retard, Fuel Trims, Boost, Fuel Pressure, etc.)?

Thanks what you say makes sense. it wasnt logged by me, the tuner used diagnostic equipment same as the dealers. And found that the car was fueling way too much.

what i dont understand is why the stock map would supply the right amount of fuel, maybe the tuners decided to increase the voltage to the fuel pump by a certain amount to give them the required fuel. And in some cars the amount of fuel would be different.

I was also suspecting sensors like O2 or MAF, but then maybe the car would throw a CEL, or be very jerky to drive.

I just dont know if i must try and do a custom tune or is there a problem with the car that i must find, and looking for such opinions.

 

[zx2man]

dont know if this is any worthwhile imput..but some tuners will "dump" more fuel to get rid of light knock at wot. How rich are you running? These cars are typicaly rich from the factory.

 

[AutoEuphoria]

better rich than lean, that's for sure!

 

[blkspeed]

well what could be throwing "too rich at idle speed" cel? and my intake is on correctly

 

[bykeryder4life]

^^your fuel trims have exceeded the +/- 80% threshold and your car threw a cel. You need to check your maf and make sure its clean, and then get a tune to calibrate it properly. OP: what kind of tunes were loaded on your car? You dont say if its AP or piggyback etc.... I get scared when you say "these tunes ran fine on plenty of other cars", because the mazdaspeed doesnt work with generic off the shelf maps. You need a map made for your specific car/ mods. If the map is calling for less fuel but the car is getting more and more rich I would suspect the tuner is ******* up somehow.

 

[bykeryder4life]

the tuner used diagnostic equipment same as the dealers....
maybe the tuners decided to increase the voltage to the fuel pump

If they did some voltage increase to your pump for fuel they dont know whats up with this car, you would need CDFP internals for more fuel volume.

Diagnostic equipment like.....what? If its a sniffer in your tailpipe for afr it's wack and wont read true afr's. You need a dashhawk or some kind of true logging device thats hooked to your ecu and reads accurate.