det sensor coming on???causes??

[str_motorsport]

hi, my gti-r seems to suffer from detonation, that is why the det sensor comes on and modify the maps on the ecu...
what couls be the causes for that??base timing is ok, fuel pump is a walbro one, clean fuel filter, cleaned injectors,maybe it is only a fuel problem?
also i noticed that the cooling fans of my gti-r only starts at 95°...is it possible to make them start earlier..but not witha switch...automatically...?
thanks

 

[j10gtr]

The det sesnsor has seen det this could be due to

Heat
Excess Boost
Incorrect Fueling
Incorrect ignition timing

Have you had a wideband on it to check the afr's?
Have you checked ignition timing following correct procedure?
Are you using a different fuel ?

Thanks
Paul

 

[str_motorsport]

i was running 0,8 bar boost, or a bit less too.
timing is set at 20° at idle with the thtottle sensor disconnected.
fuelling is standard with a walbro fuel pump and fse power boost valve set to 3,5 bar at idle.
fuel is 95 ron and i think this should be the cause, since i was running on 98 ron the night before and the car was fine and fast.but after filling with 95 i had some problems.
i have also found a broken plug today.
any ideas?

 

[Odin]

Yup don't use 95 ron fuel inless you get your car set up for it as the car's bound to start detting otherwise .

And why 3.5 bar fuel pressure it must be running rich as f*ck :? , If your only running 0.8 bar of boost there's no way that you would need 3.5 bar.

It should be running 3.0 bar.

rob

 

[Fast Guy]

Put 98ron back in and see if it cures it. Don't you have shell Vpower out there? (100ron)
If that doesn't sort it, you may need to try backing off the ignition timing a little.

 

[str_motorsport]

in italy 98 ron or shell v power 99 ron is available since 2 years now.
before that i always used 95 ron fuel, as usggested on the service manual.
it broke the plug with 95 ron fuel...and always worked good!!even at more boost!!
not melting, breaking the ceramic point of the plug.
the car is not running rich at at all.....i try to raise pressure to see if it runs richer....but no chance!!!
i really don't know which is the problem....
i have checked everything,fuel pump voltage and i have also added a new relais and new wires, because i found that voltage to the pump was low, but this has not fixed the problem...
now it seems that the AFM voltage is a bit too high that stated on the service manual...could this be the problem?
could a faulty head gasket cause detonation?