hey,
planning to have a carbon clean-up on a mk2.5 1.4lt done 40k. shall i reset the ecu for any good reason? if yes, anything special to be done except disconnecting (a few hours) and reconnecting the battery,running idle to heat up, then driving normally for a plenty of miles for a successfull remap??

any suggestions, ideas, please

resetting the ecu is not remapping.
if you run on a good fuel you wont have no carbon

yes you will

even a really clean engine with decent fuel all the time will build up *some* carbon (cheap fuel, stop start driving, lack of hard use, nasty engines all cause lots ).

decarboning by hand is preffered! did it with water spray gun on the turbo volvo and it left a right mess in the exhaust (not cat to worry about).

if its a self learning ecu, won't it learn its cleaner anyway? or best to start again, mk2's are tricky afaik

you did what take a head off a car thats been run on top fuel, ie optimax (now v-power) and take one off a car that hasnt

a car thats been run on optimax/98ron fuel/or at least had some kind of octane booster in it for 4years out of 4years, and has two cylinder heads

and several cars that have been run on total pishwater for decades.

yes the audi was cleaner, but there was still flakey carbon on the inside of the heads and the exhaust ports were just as disgusting as ever

If you got two identical cars, drove them exactly the same (i.e follow each other everywhere) and ran one on 95ron and one on 98 ron (or whatever performance fuel there is) then you'd see a difference, but I'm telling you, it would still have carbon in there.

a little carbon isnt going to make a lot of diffrence, not worth an engine strip imo

suppose your not going to know until you crack it anyway.

the 2001 audi had 108,000 miles on it when we did it. it now has about 115,000 (had the car from new, but it goes all over the country and generally is getting used to death. which is the only way buying a new car is financially viable

im pretty sure that I have carbon build up within the engine since the fuel is not of top quality here. so guys what do you think about reseting after carbon cleaning, unnecessary?

if you are taking the head off, then you will disconect the battery anyway, so it will reset, no need to warm up at idle first though, just drive it

It will need to go to a dealer with examiner Dave as the system will need resetting as if the gentleman is doing the job properly that bottom pulley will be removed and the phonic wheel will neeed relearning. Also you can only do a full reset using examiner or perhaps another diag tool, disconnecting the battery does nothing on the latest engine ecus.

NumanR

guys,
applied the carbon cleaning, black stuff had come off from the exhaust for a couple of secs when revved hard after the process. I think it works...
no reset, by the way...