kongo127 0 Posted February 11, 2004 Hi folks! How can i know if the lamda probe is dead? What would happen in that case? My muffler is always popping! And the car is a bit slow! But if i advance the timing to the maximum (almost knocking) the popping dissapears, and the car runs much better! Shouldn´t the ECU advance ignition timing automaticly till the knock sensor detects it? To then back it off a bit? Why can i advance so much (rotating the distribuitor manually)? It is possible to run much more timing, and the ECU doesn´t make it automaticly. There is still a problem... when i advance the timing, the MFA doesn´t show any fuel consumption! (completely impossible). Timing is done by the blue temperature probe, right? What is going on? Any ideas? :? Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 12, 2004 You can test the Lambda buy putting a high impedance voltmeter across the white wire and earth. Engine needs to be up to temp. It should be seen to fluctuate between 0.1 - 0.9V. The meter won't be able to keep up with the voltage changes but so long as it's flicking up and down in that range, it's doing it's job. If it's dead, you'll burn out the cat but you probably won't notice much else tbh. The lambda has nothing to do with timing, the knock sensor takes car of that, well, it doesn't 'advance' the timing, it just tells the ECU to retard it if detonation is heard. The lambda probe is ignored at wide open throttle anyway, it's just there for emissions, better economy at low to mid revs and to ensure the engine is running at Stoich to protect the cat. The blue temp sender just tells the ECU when the engine is cold so it alters the fuelling accordingly. Quote Share this post Link to post Share on other sites
ZeroK66 0 Posted February 12, 2004 Is there a separate sensor for water temp then? Quote Share this post Link to post Share on other sites
h100vw 0 Posted February 12, 2004 Is there a separate sensor for water temp then? The Blue coloured one feeds the ECU the Black one does the temp gauge. One quick test to eliminate the blue plug. Switch the plugs over Blue to Black and vice versa. If the running improves there is your man. No need to drain the coolant and less than a tenner to buy new. Gavin Quote Share this post Link to post Share on other sites
Henny 0 Posted February 12, 2004 No need to drain the coolant and less than a tenner to buy new. Just make sure you do it when the engine's cold and take the expansion tank cap off first... :wink: If you do it while the coolant system's pressurised, it fires the sender and a jet of coolant a few feet into the air! :shock: :oops: found that one out the hard way.... :oops: :roll: Quote Share this post Link to post Share on other sites
GazzaG60 0 Posted February 12, 2004 check the harness on the probe. check the 2 plugs and the spades haven't slipped out. check the lavinder wire isn't broken and the earth. probe needs a v good earth. these wires get hard with heat over time and are brittle so be careful. get a af gauge. i bet you see nothing on it when its popping. the system is dumping fuel in at this point as it think your lean. ive had issues in the past with this. a bad probe creates a bad transitional period to the map and brings on lots of spluttering. also like the others peeps have said the Blue temp sesor. clean the crap of the bottom of it too when its out. Quote Share this post Link to post Share on other sites
