slight problem, possible throttle body?

[micra_kow]

Hello chaps, 1st time poster, just bought our lass a 2001 micra 1.0s and need a bit advice

When cold and trying to accelerate, it hesitates and feels like its misfiring. Petrol consumption is terrible and she says it cut out on her today when idling. I drove it last week and it only happened when cold, once engine was hot it felt ok. Stopped hesitating after about 15 mins or so, but recently she tells me its getting worse.

Was thinking a good service and changing the plugs or possible o2 sensor etc might get away with it untill I found out about the usual k11 problem with the throttle body.

Saying that, the symptoms Ive read seem a bit more drastic to whats actually happening. Maybe because its on its way out??

Apparently I can solder the wires, thats not a problem.

Question is, Is the guide on here the same as her 1.0 engine? i.e circuit board in same place

I'll give it a go, possible quick easy fix that could sort it is always worth a go first.

thanks for any replys (Y)

 

[Dave_Ally]

The throttle body changed in September 2000 to a Bosch unit, it's normally the MAF that plays up in these or you can look at the front oxygen sensor.

 

[Stewpotz]

mine was doing this over the seasonal period last year, when it was started in the cold it wouldnt like to go, put your foot flat down and there was nothing until it burst into life.

dont know what the problem was as it decided to stop doing it in end of jan and hasnt done anything since even with a few cold morning starts it is all fine

 

[micra_kow]

The throttle body changed in September 2000 to a Bosch unit, it's normally the MAF that plays up in these or you can look at the front oxygen sensor.

So do the post 2000 throttle bodys not need soldering, did these not have the same problem as earlier models? So is the MAF known to be a problem on the facelift models?

No MIL engine light is flashing at all. But when trying to accelerate it practically restricts the car to a stop.

If anyone has experienced this or knows any usual problems with this model, please let me know thanks

 

[Shaun]

it does seem like the throttle body/maf however they are different to the earlier ones so i couldn't advise

 

[frank]

see how it runs with the maf disconnected (they tend to run better when the maf is knackered )

 

[micra_kow]

So if I disconnect the maf whilst running, correct me if Im wrong but the car should run awful. If it doesnt change, maybe the maf is at fault. But you saying it actually runs better with a faulty maf is throwing me a bit.

If its not the throttle body, I would point it at the maf or o2 sensor as they are technically the 'pre' and 'post' air flow sensors really and might be the reason why its loosing so much fuel and misfiring under load when cold (and possibly hot).

Any more advice/info is greatly appreciated before I spend hours tracking down the problem 'once ive got a minute', cheers

 

[frank]

thats what robb said on post #4
http://www.micra.org.uk/threads/442...t-code-on-a-post-2000-K11-Micra-Please-Help!?

 

[micra_kow]

cheers for that frank, reading that thread has cleared a few things up for me.

As far as I can gather, on the post 2000 model, the MAF sensor CAN be removed and renewed without renewing the throttle body (hopefully).

I just hope it will solve problem thats all, part is only 27 quid. But no MIL light so no fault code.

What I'll do is disconnect the plug on the MAF, clean sensor with electrical/carb cleaner or whatever I can find in garage and see how it runs with and without sensor connected.

I think after doing that, it SHOULD point me in the right direction. Be it either the sensor or it will make me look elsewhere. Just a process of elimination and logical thinking without having engine fault code.

For info, checking circuit should read battery voltage at terminal 2 and 5volts(ish) at terminal 4 on plug. (With ignition on).

 

[micra_kow]

well hey presto, removed the plug from the MAF sensor and ran perfectly ever since. Circuit is fine so ordered new sensor as Im sure it's that now. Cheers!