ive fitted a new one to the car 2day it was a bosch 3 wire unerversal one every thing was ok untill about 15minits into driving the car just cuts out i tried starting it and the is no engine warning light or cat on fire light the engine will try and start but nothing??? ive checked all the fuses and there all ok any ideas ? its a 94 wrx

 

should of reset the ecu ?

 

Has the lamba sensor got a red,white and black wire???
As im sure a universal sensor is the wrong one
"but i may be corrected"
DEKA

 

If the car was warmed up when it cut out (should be after 15 mins) then dont think it would be the lambada as the ecu would not be using it for the fuelling.
I would certainly try the diagnostics though to see if that does bring anything up.

 

jaytc2003

That's not right, the ECU only starts to use the lambda sensor once it has warmed up, so after 15 minutes it may have just started using it.

andywrx
The car should start fine with the sensor disconnected (it just disables the closed loop fuelling), but will light the engine check light. If it starts like that then check you have it wired correctly - I've never used a universal sensor so don't know how it gets attached to the existing connector.

Matthew

 

I thought it was the opposite? Thought the closed loop fuelling was when the car was cold and then the ecu reverted to map based fuelling when it warmed up?

 

No, closed loop fueling is used to keep the catalyst happy while you are driving gently and ecu reverts to map based fuelling once the revs get above about 4000, the boost gets above 0 or you have your foot to the floor. The lambda sensor doesn't work until it gets hot (nor does the catalyst, but that's another issue) which is why it may not have an affect for the first 15 minutes.

If you're interested I have some logs that show the lambda voltage gradually changing as it warms up, then cycling as it moves to closed loop operation.

(Apologies to andywrx for hijacking your thread)

Matthew

 

cheers for the help lads i tried disconecting it and starting the car still no joy

 

Hi
Did you find a solution to this problem ?
I think I have a similiar one as well with a universal lambda