petercain0110

this is driving me nuts ..

this is what i understand ..

car started from cold, ok .. car ran fine to shop 1 (1 m) .. after shop 1 car started ok, but sluggish .. car ran to shop 2 (1 m) .. after shop 2 car started ok, but sluggish ..

car then ran for a while (1-2 m) then cut out .. car will not start .. customer left car where it died ..

vagcom shows brake light switch open circuit .. new brake light switch on order ..

vagcom does NOT show engine m u ..

fuse 29 blown ..

replace fuse 29 .. car starts .. runs badly for few seconds, petrol heavy .. fused 29 blows ..

replace fuse 29 .. blows again almost straight away without even trying to start engine ..
(tried replacing 20a with 30a fuse, heard fuse pop as turned ignition key from 0 to 1)

any ideas ?...

has someone seen this before ?.

thanks ..
************

turbo510

If fuse 29 is the same as fuse 229 on U.S. cars, then that's for the O2 sensor heaters. Try disconnecting the black oxygen sensor connectors and see if the fuse still blows. And avoid putting in higher amp fuses, because this circuit is powered through the fuel pump relay, which may get burned contacts.

Also, VAG-COM will show the brake light switch open every time unless the brake pedal is depressed. The switch may be OK.