Hi Guys,
my 93 (no OBD etc, 1FZFE) just failed with about 2 x the limit of NO. Other readings within limits.
My (front) O2 sensors are brand new Toyota, but I will still check to see if the voltage is "oscilating" as it should.
Criticise my logic here:
Assuming the car is going into closed loop (why would it not - faulty cooland sensor?), whatever goes on wirh regard to mixture should be sorted by the closed loop operation, unless air is leeking into the exhaust, giving the sensors a false lean reading ?
Unless the value are beyond the scope of compensation ?
I'm going to look at air filter.
Plus, wires, rotor and cap all only a few thousand miles / year or two old (yup it doesn't do many miles).
Other info - car has a restricion in the air intake ion the form of a LPG mixer venturi - it's dual fuel LPG - passed OK before though.
VAF might need some adjustment ?
Car has slighlty less power than my other 1FZFE.
No Check engine light or codes.
EGR is blanked off - this was not the case when last tested - but this shouldn't affect anything at idle, and regardless woudl affect NOX, not CO ?
PAIR system removed - as above - was not the case when last tested, but that just injects air on overrun - unless my blank plates are leaking ?? Can reinstate, removed as it doesn;t have any useful function on LPG.
Lastly, I wonder if running mostly on LPG and effectively not using the fuel injectors except at first startup has allowed them to get cruddy / gummed up ? An injector / fuel clearner (BG44k or somesuch) is on order.
Any help and advice appreciated. All my searches have fundamentally pointed to o2 sensors or clogged air air filters - my O2 are new.
Cheers - JB
my 93 (no OBD etc, 1FZFE) just failed with about 2 x the limit of NO. Other readings within limits.
My (front) O2 sensors are brand new Toyota, but I will still check to see if the voltage is "oscilating" as it should.
Criticise my logic here:
Assuming the car is going into closed loop (why would it not - faulty cooland sensor?), whatever goes on wirh regard to mixture should be sorted by the closed loop operation, unless air is leeking into the exhaust, giving the sensors a false lean reading ?
Unless the value are beyond the scope of compensation ?
I'm going to look at air filter.
Plus, wires, rotor and cap all only a few thousand miles / year or two old (yup it doesn't do many miles).
Other info - car has a restricion in the air intake ion the form of a LPG mixer venturi - it's dual fuel LPG - passed OK before though.
VAF might need some adjustment ?
Car has slighlty less power than my other 1FZFE.
No Check engine light or codes.
EGR is blanked off - this was not the case when last tested - but this shouldn't affect anything at idle, and regardless woudl affect NOX, not CO ?
PAIR system removed - as above - was not the case when last tested, but that just injects air on overrun - unless my blank plates are leaking ?? Can reinstate, removed as it doesn;t have any useful function on LPG.
Lastly, I wonder if running mostly on LPG and effectively not using the fuel injectors except at first startup has allowed them to get cruddy / gummed up ? An injector / fuel clearner (BG44k or somesuch) is on order.
Any help and advice appreciated. All my searches have fundamentally pointed to o2 sensors or clogged air air filters - my O2 are new.
Cheers - JB