Exhaust light on after sports cat

[bendella]

ok guys good news passed the mot today and emmisions spot on

had to get it remapped today aswell and the difference in torque mid range is more than enough with the sports cat. I have an ABT quad back exhaust that i got of ebay for £25, yes could not believe it myself as they sell for around £800 now from ABT uk. The nice lady said she has no use for it anymore so got a bargain i would say. I am going to get that on and post some pics on when done.

[bendella]

Ok So Now exhaust light off, remapped with loads of mid range  torque but fuel consumption very high-normal driving no booting, from my search regarding remaps i figured i'd get better mpg. Any suggestions on where to start?

[bendella]

So with the remap the fuel consumption is very poor and i thought remaps would better fuel economy. i spoke to the guy who did the remap and he says the car will run rich to accomadate for the power demands. My problem is that i do normal driving without going at it hard and still uses alot of fuel. The guy said that he had to decat the car to turn the exhaust light off which make think i could have forked out less and got a decat in the 1st place and not pay alot for a sports cat.

Now my question is that can this car be remapped without decatting it and keep the exhaust light on or am i wasting my time. Guys i really need to sort this problem out so if you can make good suggestions the pls fire away

[bacillus]

Now my question is that can this car be remapped without decatting it and keep the exhaust light on or am i wasting my time. Guys i really need to sort this problem out so if you can make good suggestions the pls fire away

Never had a cel when using revo stage 2 /2+ with a milltek tbe. Sounds like the problem is your tuner's mapping.

[bendella]

I have a piper sports cat with mid box and no rear, Not sure what to tell the tuner as to how he should adjust the map so i get it remapped without a decat and still keep the light off. With regards to it over fueling is this normal? When i had my cambelt changed at Vagco, Simon felt that the car was running too rich and after revving it a few times the exhaust pops really loud, this he said was unburnt up fuel in the exhaust, hence over fueling

[bacillus]

I have a piper sports cat with mid box and no rear, Not sure what to tell the tuner as to how he should adjust the map so i get it remapped without a decat and still keep the light off. With regards to it over fueling is this normal? When i had my cambelt changed at Vagco, Simon felt that the car was running too rich and after revving it a few times the exhaust pops really loud, this he said was unburnt up fuel in the exhaust, hence over fueling

Who is your tuner as it sounds like your map isn't optimised for the car.

[bendella]

he is a local guy in Hull and he downloads all the info from the car and sends it to a vw tech who does the remap and then sends the file back to him the downloaded back to the car. I tried telling him the remap needs looking at and he says it's running rich due to the remap and that's why the car is at 300bhp cause of a performance tune. Simon thinks that the car is not operating efficiently, i agree

[PDT]

A few questions:

Was the car dyno tested to get a true AFR?
Was the car datalogged before or after the mapping?
If its running rich, do you have any actual evidence of this or is it just your tuners guess?

[bendella]

No Dyno
No datalogue
The tuner guess it's running rich due to higher demands due to the remap

What would a rolling road tell me about this problem?

[PDT]

with no datalogging and no dyno testing your map is just a guess by someone on the end of an email. What you need to now do is take it to a specialist with datalogging equipment and ideally a dyno and check various parameters such as AFR's Boost, ignition pull, engine load, throttle angle, fuel pressure demands etc....

The dyno is usefull as you will be able to test the car in every gear under varying load conditions / throttle positions and get accurate repeatable results without the danger of doing this on the public highway.

Ideally your tuner should have done all of the above, at the very least the datalogging as part of the service. But I guess you didn't pay specialist money for the work?

There are some very friendly and helpfull people on here that can do the basics for you with Vagcom, check the vagcom section for someone local that can help you 

[bendella]

that sounds indepth and possiblily what should have been done initially, now i will have to get it done as you say and this should sort the problem. looks like i am done talking to the guy who remapped it as he just makes excuses now. Cheers for the detailed info

[Hedge]

Get the clown that mapped it to flash it back to stock. I ran stock with a turbo back Milltek without a light.

Even if you get the exhaust light on that's got to be better than washing everything in petrol. 

[bendella]

Looks like the only option now then start from the begining with a genuine remap, just thought he was closer to home and would be better if anything went wrong but i guess u learn

[GrayMK5GTI]

Looks like the only option now then start from the begining with a genuine remap, just thought he was closer to home and would be better if anything went wrong but i guess u learn

Your best bet would be to use one of the recommended tuners on this forum, ie:

-PDT
-R-Tech
-JKM

To name a few. . .

[bendella]

Ok so i just had a chat to David from PDT (very helpfull) and looks like i am going to get the car in to them and get i done right this time, no messing about now. So hopefully i will post back with some positive results soon