Ok see if you lot can help, I have a small turbo Escort Cossy with a GGR chip I have used this chip for over 10,000 miles with no problems until now it has started to misfire when on full boost 18 psi and for a while had problems with boost waving up and down on the motorway in 5 th gear. So I disconnected the amal valve and ran the pipe direct to the actuator and had to set it to 12psi to get rid of the misfire.

I have ran is like this for 8 weeks now as I have not had the time to look at it but today I started to misfire again with 12psi only a bit also you can smell it is running rich.

I think it may be the Map sensor but I don’t know I have ran it with no chip and also ran it with a supper chip and it is still the same, also the other day it would not start but when it did it did not rev and though loads of black / grey smoke out !! so I checked all the electrical plugs and all was fine so tried again and it was fine ??

Any help would be nice.