Hi looking for some advice, i have recently bought a Mark 2 GTI which has been converted to the 20V engine with the AGU engine in it. We have finally managed to get the car running but it has been over fuelling massively causing the car to run like a pig when driving around the streets, was advised to change the ECU which is what we have done and it has improved things but still does not run correctly when driving in built up areas but on the motorway she flies. We have noticed that the car is still running on the old fuel pump from the Mark 2 GTI which i have been told could be the issue, I have also been told that i need to get a live re-map done which I have looked in to and they want about a £1000 pound to do. I don't mind spending some money on it as long as i know it is going to sort out the issue if anyone can advise on this problem would be very grateful.
Hi,
If your car is over fueling, I wouldn't have thought the fuel pump was at fault.
Might be worth checking what the fuel pressure regulator and injectors are.
If they've been changed, you'd need it mapped to account for the mods.
Hi thanks for that it looks like that is the way i need to go with it. The issue for me is that if i spend the money to have it re-mapped is it going to sort the problem out, i don't want to spend that sort of money and then find that i am still in the same boat. Thanks again
Yes, live mapping is not cheap.
Before you go down that route, make sure you have done a health check on the car.
Boost leaks will cause over fueling too, so get a pressure tester on it and see if you have any.
Another way is to get some clutch cleaner and spray it around joints and gaskets while the car is idling.
If the idle changes, you have a leak there. Careful though, it's flammable, so keep it away from the exhaust!