Hi Guys,
I have a Lotus Exige with a Euro Spec K20 type R engine in with GT30 turbo. The Lamda gives an output (green wire) of about 2.5V on idle resulting in an A/F ratio of reading about 25 on the K-Pro. It moves up and down with the revs, but is totally wrong. The wiring is done according to the race car wiring diagram on the Hondata website. I have the wide-band lamda and it should be reading under 1V as far as I am aware. The lamda is brand new. My aftermarket system from Innovate reads A/F of about 13.5 at the same time and the car runs properly.
Any advise? : :?:
Air Fuel Ratio
First, what ECU are you using and what type of lambda sensor?
If you are using a PRA ECU then you'll need to wire the vehicle as per the Euro CTR wiring diagram in the manual - our race car wiring diagram is for a wideband o2.
If you are using a PRB, PRC or PRD, then you cannot diagnose the lambda sensor with a voltmeter. The lambda voltage is irrelevant - it is all current driven. Also it is best not to hook anything, including a multimeter, into the lambda sensor as it can damage it. Chances are the lambda sensor is the wrong type or has been damaged. Note that the sensors die from vibration as well, so the correct flexible joints in the exhaust system and engine/chassis isolation is important.
If you are using a PRA ECU then you'll need to wire the vehicle as per the Euro CTR wiring diagram in the manual - our race car wiring diagram is for a wideband o2.
If you are using a PRB, PRC or PRD, then you cannot diagnose the lambda sensor with a voltmeter. The lambda voltage is irrelevant - it is all current driven. Also it is best not to hook anything, including a multimeter, into the lambda sensor as it can damage it. Chances are the lambda sensor is the wrong type or has been damaged. Note that the sensors die from vibration as well, so the correct flexible joints in the exhaust system and engine/chassis isolation is important.
Hondata
Thanks for the response,
I have the American spec K-Pro, as well as the wideband O2. I specifically purchased the American spec equipment so that I could log A/F ratios. The K-Pro and O2 are brand new. The readings were at 25A/F ratio before any tests were done on the O2 sensor. It was reading incorrectly from start-up and still reads incorrectly.
I slotted pins into the A22 and A16 connectors so that I could duplicate the race car wiring, as my harness was Euro spec. I am getting no error codes on the ECU for heater or O2. If I put it into closed loop, the car totally overfuels on idle, trying to compensate for the 25 A/F ratio the ECU is seeing.
Your advice will be greatly appreciated. I have basically disabled the closed loop for the moment. The car runs perfectly.
Thanks
Tjaart
I have the American spec K-Pro, as well as the wideband O2. I specifically purchased the American spec equipment so that I could log A/F ratios. The K-Pro and O2 are brand new. The readings were at 25A/F ratio before any tests were done on the O2 sensor. It was reading incorrectly from start-up and still reads incorrectly.
I slotted pins into the A22 and A16 connectors so that I could duplicate the race car wiring, as my harness was Euro spec. I am getting no error codes on the ECU for heater or O2. If I put it into closed loop, the car totally overfuels on idle, trying to compensate for the 25 A/F ratio the ECU is seeing.
Your advice will be greatly appreciated. I have basically disabled the closed loop for the moment. The car runs perfectly.
Thanks
Tjaart
Following the engine swap diagram should work for you. Do not use any of the relays in the lotus - they are not reliable and don't use the correct switched/un switched power. Use fresh wiring and relays.
Lastly, if you've connected a single wire incorrectly to the lambda and powered the ignition on, chances are the lambda controller in the ECU is dead. The only way to test is by ECU substitution, but fix any wiring issues first.
Lastly, if you've connected a single wire incorrectly to the lambda and powered the ignition on, chances are the lambda controller in the ECU is dead. The only way to test is by ECU substitution, but fix any wiring issues first.
Hondata
Hi 6spd,
Does your a/f ratio change when you rev the engine?
My target air fuel ratio reads 14.7, my a/f ratio reads between 25 and and 29 and moves up and down with changes in the engine. The movements up in down in the air fuel ratio correspond to up in down movements on my external Innovate system.
Does yours do the same?
Does your a/f ratio change when you rev the engine?
My target air fuel ratio reads 14.7, my a/f ratio reads between 25 and and 29 and moves up and down with changes in the engine. The movements up in down in the air fuel ratio correspond to up in down movements on my external Innovate system.
Does yours do the same?
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cstyleaccord
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