Malfunction Light/sensors

[campioni06]

Hi, my girlfriend is having probs with her MR2, Y reg vvti engine, same engine as Avensis?

Malfunction light came on so she took it to Mr T as under warranty. Got repaired but no paperwork was given to her, they just said they'd replaced a sensor.

24 hours she's driving and guess what? Light comes on so she's waiting for them to pick it up again.

Is it now just a matter of them replacing the sensors one by one?

I'm sure if she was paying for this they'd have told her to get them all done at the same time

Anyone had similar probs? Cheers.

[uumode]

Hi, my girlfriend is having probs with her MR2, Y reg vvti engine, same engine as Avensis?

Malfunction light came on so she took it to Mr T as under warranty. Got repaired but no paperwork was given to her, they just said they'd replaced a sensor.

24 hours she's driving and guess what? Light comes on so she's waiting for them to pick it up again.

Is it now just a matter of them replacing the sensors one by one?

I'm sure if she was paying for this they'd have told her to get them all done at the same time

Anyone had similar probs? Cheers.

others have reported similar.

Also similar reports with VW.

[campioni06]

Eventually got the car sorted so the engine light stays off but....since then has a rattle coming out the engine bay.

Girlfriend took the car back twice (to Jemca North London) and twice got fobbed off.

I went with her Saturday, kicked up a fuss in the showroom and suddenly their attitude changed. Got taken to the managers office who apologised for the *****-ups and poor service.

Seems like you have to fight to get things done with Mr T. Annoying really

[bgorman]

Eventually got the car sorted so the engine light stays off but....since then has a rattle coming out the engine bay.

Girlfriend took the car back twice (to Jemca North London) and twice got fobbed off.

I went with her Saturday, kicked up a fuss in the showroom and suddenly their attitude changed. Got taken to the managers office who apologised for the *****-ups and poor service.

Seems like you have to fight to get things done with Mr T. Annoying really

Had the exact same fault on our roadster, we took it to main dealer who used the code reader and he told us that the fault was a Fault on the MAF (air flow) sensor. He cleared the fault and ordered a new one for £150, but it would take about a week to arrive.

Two days later the light came back on, so I phoned a local independant garage/tuning outfit," oh that old one again!" he said,bring it round now and Ill look at it .

He took out the MAF sensor (2 screws and 2 minutes) "ah yes " he said "just needs a good clean"

He then spayed the inside with carb cleaner and gently swabbed the 2 thermistors inside with a cotton bud,replaced it then cleared the light by dissconnecting the Battery -ve for 1 sec (this didnt even lose the clock or radio data!). That was 2000 mls ago, light has stayed off car runs like a dream.

Thus we saved 150 notes and learned something as well! He told us that this works on many makes of car and people spend ££££££s and alot of time replacing oxy sensors and the like to no avail.

Incidentally, our MR2 had a standard air filter and all the other parts in the air intake were spotlessly clean

the car only having 37000 mls on it.

In view of this I think it will be a good idea to clean it maybe once a year or so anyway.

[campioni06]

Got ours done under extended warranty so foc (apart from the £450 cost for the warranty of course) :P

Cheers though - worth knowing that for when warranty runs out

[Starensis]

My warning light came on last week & was diagnosed as O2 sensor in manifold ( Bank 2 sensor 1 ). Changed both sensors ( to be safe ) & cleared memory by removing EFI fuse in engine bay fuse box ( best to leave for a couple of mins, with ignition OFF ).

Drove down the road for 3/4 miles & light came back on again

Keeps flagging same fault even though I've changed both sensors. All wire positions in new sensors are as old, so not sure what else to do now.

Anyone had this problem?

BTW, I have a list of codes for VVT-I engines if anyone needs to translate one.

[uumode]

My warning light came on last week & was diagnosed as O2 sensor in manifold ( Bank 2 sensor 1 ). Changed both sensors ( to be safe ) & cleared memory by removing EFI fuse in engine bay fuse box ( best to leave for a couple of mins, with ignition OFF ).

Drove down the road for 3/4 miles & light came back on again

Keeps flagging same fault even though I've changed both sensors. All wire positions in new sensors are as old, so not sure what else to do now.

Anyone had this problem?

BTW, I have a list of codes for VVT-I engines if anyone needs to translate one.

Check the car Battery? If the Battery hasn't been changed it's around 5 years old - could be it is tripping the warning sensors with a slightly low voltage? A slightly weak Battery is known to trip other warning sensors such as traction control, abs and ECU lights.

[Starensis]

My warning light came on last week & was diagnosed as O2 sensor in manifold ( Bank 2 sensor 1 ). Changed both sensors ( to be safe ) & cleared memory by removing EFI fuse in engine bay fuse box ( best to leave for a couple of mins, with ignition OFF ).

Drove down the road for 3/4 miles & light came back on again

Keeps flagging same fault even though I've changed both sensors. All wire positions in new sensors are as old, so not sure what else to do now.

Anyone had this problem?

BTW, I have a list of codes for VVT-I engines if anyone needs to translate one.

Check the car Battery? If the Battery hasn't been changed it's around 5 years old - could be it is tripping the warning sensors with a slightly low voltage? A slightly weak Battery is known to trip other warning sensors such as traction control, abs and ECU lights.

Mmm, everything is OK with battery at the moment. Just wondering if a Non-Toyota sensor would throw this fault again.

New sensor is same as one removed ( same wire colours ), so would assume they are compatible.

[Starensis]

Sorted it!

On the new sensor there was 2 black wires ( heater ), 1 blue & 1 white. It does not matter which way the 2 black are refitted ( they obviously need to be in same cavities ), however, the white & blue are critical.

Blue & white are the sensing side of the sensor. One is earth the other is signal back to ECU. If you get them crossed ECU will be receiving continual earth signal.

Swapped Blue & White wires & all appears OK now. Just make sure if you are fitting new terminals you get this right.

[campioni06]

Well 3 weeks later, 2 new oxygen sensors, and half a dozen technicians saying theres nothing wrong with her car the missus finally got a call today to say they're gonna have to replace the engine. Haven't yet told her why but she's gonna find out. Lucky I talked her into buying the extended warranty £500 compared to cost of new engine and Mr T hourly labour charges.

Anyway shall let you know what the problem was with the engine. But it just goes to show you gotta push these people to get things done.