just recently come come back to MX-5 ownership after owinging several Hondas. Had my 2013 Sport Graphite model about 8 months now. Unfortunately the steady yellow warning lights illuminated on the dash.
Car tuns perfectly fine. Had it checked out and fault P0131 o2 sensor circuit low voltage bank 1 sensor 1. Emissions checked and all within normal parameters. Mechanic thinks it’s the heating element in the sensor that’s faulty and ok to keep running it and ignore the light due to huge cost of replacement.
Priced up the part including VAT is best part of £500
any ideas anout cheaper remedies other than removing the dash bulb lol
chasing up potential goodwill with Mazda UK but not holding out much hope As the cars not always been serviced by an approved Mazda dealer
The lambda sensor heater is required to ensure that the correct operating temperature is achieved. It may be that your garage tested the precat lambda once engine and exhaust up to temperature. This may produce the correct conditions with minimal or no use of heater. Emissions problems would occur in the critical period when the engine is started from cold and getting up to optimum temperature.
Essentially the precat lambda sensor need replacing.
Poster above has already identified a mainstream part for a third of the price you have been quoted by the dealer.
Thanks Ray. I seriously hope that’s the correct one. Mine seems to be unique as my engine is higher output around 150bhp and that’s why it’s so expensive. Will call them just now
update. Guy seems 100% confident it’s the right part. Out of stock for another 3 weeks but I don’t mind waiting to save about £300
Hope that means I can continue using the car without causing any further damage. Its my daily drive so unable to take it off the road while waiting on the part.
Talking of emissions warning light on, mine is on as well.
Had it read with a code reader and it recorded p2187 which means mixture weak at idle.
Anybody any ideas on that one.
It does seem to hunt up and down a little bit when ticking over, as if it’s trying to compensate for the mixture, I mean is it actually weak
or does it just think it’s weak due to faulty component misreading?
Will it do any harm if left at least for the time being?
Paul.
P.S. Never had these probs with my 1972 Ford Escort!
My daughters Astra Convertible had the same fault code, which was fixed by replacing the Lamda sensor at the manifold.
However, what was a little worring was the fact that the Garage she bought it from mentioned that they’s fitted a new Lamda sensor when she bought the car.
Strange for it to go through 2 in about 8 months.
Also it seems the EML will be an MOT failure from May this year (again)
Paul - an A2187 error code is more complicated as does not specify a single cause. I found this…
DTC P2187
Fuel system too lean at idle
DETECTION CONDITION
PCM monitors short term fuel trim (SHRTFT) and long term fuel trim (LONGFT) during closed loop fuel control at idle. If the LONGFT and the sum total of these fuel trims exceed preprogrammed criteria. PCM determines that fuel system is too lean at idle.
Diagnostic support note
This is a continuous monitor. (Fuel system)
The MIL illuminates if the PCM detects the above malfunctioning condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
PENDING CODE is available if the PCM detects the above malfunction conditions during the first drive cycle.
Fuel leakage on fuel line from fuel delivery pipe and fuel pump
Leakage exhaust system
Purge solenoid valve malfunction
Purge solenoid hoses improper connection
Air suction in intake air system
Insufficient engine compression
Variable valve timing control system improper operation
PCM malfunction
…
A lean mixture can cause issue, typically with damaged pistons and bore.
David
Given your situation I would source and fit a replacement sensor quickly but would continue to drive the car if it cannot be avoided. Increased emissions and fuel consumption associated with your issue unlikely to cause damage in the short term.
I had that sensor replaced by my local garage recently. They charged me £259.20 which was broken down as
£44 Diagnostic check (I had already identified the fault code though)
£150 Lambda Sensor
£22 Half hour labour
£43.20 VAT
I knew the sensors were expensive if they came from a Mazda dealer and had discussed this with my garage. They were confident they could get one cheaper and they did.
Crikey, thanks for all the info, and I was hoping for a good nights sleep tonight!
The car is going for an MOT in April. I normally take it to an independent garage around the corner from me who have the latest Bosch diagnostic
equipment I understand. Still, I think this sounds like a tricky one for them to pin down. Might suggest them changing the HO2S and MAF and hope that
covers the fault, Of course if it don’t then that’s money down the drain. Could just say fix it and leave them to it - their the one’s with all the kit
and knowledge.
I do wonder if this one is best left with a Mazda garage being masters of just one make of vehicle. I would appreciate comments on that one.
Because it’s registering weak mixture only at idle I assume (hope) that the mixture is correct under normal driving conditions so not doing damage whilst
under load.
It runs beautifully whilst driving, never misses a beat, fuel consumption is where I expect it to be and starts first time hot & cold.
Just to let you know finally sorted the engine warning light issue. Was def the nearest oxygen sensor to the manifold which wasn’t the easiest thing to fit but at least it came off with a little persuasion. luckily I got hold of a friend in the motor trade n even though it still cost me £240 inc VAT it’s still whay cheaper than Mazda.