[JoeH147]

Hi, I've got a '05 GT 2.0JTS that has had its MCSF warning on constantly for the last few months.

I'm getting the P1173 and P1176 codes which relate to the long term fuel trims, and once deleted they return with 25 miles (mainly short runs, more of which further on). However, once I take it for a long drive, say 300miles plus on the motorway, the light goes out after the next 3 starts. The classic "Italian Tune Up". The fuel trims must come back within range as the engine is doing different work to its normal short trips of 20 miles a day.

Its also idling rough and generates a lot of thick white smoke when cold, if it was a carbureted car I'd say it was running rich, once warmed through its fine. Obviously it doesn't like short journeys, its like it is overfueling and sending the fuel trims out.

- I've had new lambda sensors and they have been hard wired in.
- Getting OK MPG, average 28mpg normal, 33mpg on the motorway.

Does this sound like I need a new MAF or a case of giving the old one a clean?

Any advice or similar experiences greatly appreciated.

 

[Afco]

Jts needs fast and long driving otherwise when you drive always short trips ( say the engine stays cold ) after a short laps of time you will have faults.. What can help is from time to time ad some injector cleaner to the fuel, normaly the faults then not come back so fast.
The first time you do this do it on a full tank and ad a double dose

 

[JoeH147]

Jts needs fast and long driving otherwise when you drive always short trips ( say the engine stays cold ) after a short laps of time you will have faults.. What can help is from time to time ad some injector cleaner to the fuel, normaly the faults then not come back so fast.
The first time you do this do it on a full tank and ad a double dose

Thanks for getting back, I've been using injector cleaner every other tank, hasn't helped. Unless its just poor fuel where I live?

 

[JoeH147]

So, changed the MAF, kept the original housing and just replaced the sensor with the correct new Bosch part.

Instantly got a P1151 error, lambda sensor, my diagnostics tool can't tell me which bank though. Wonder if I've disturbed some connections, two have been hardwired by the garage I was told, but they must be the post-cat ones as I've still got the ****ty connectors on the front by the radiator. Might try cleaning and reconnecting these. Only other thing I could have disturbed is the intake, maybe it has a slight vacuum leak.

Every connector has brittle and broken plastic sheething around it, maybe damp is getting in now and again.

Seems its true about JTS's and their sensitive MCSF failure lights! Its running ok, so not massively worried at the moment...

 

[Afco]

So, changed the MAF, kept the original housing and just replaced the sensor with the correct new Bosch part.

Instantly got a P1151 error, lambda sensor, my diagnostics tool can't tell me which bank though. Wonder if I've disturbed some connections, two have been hardwired by the garage I was told, but they must be the post-cat ones as I've still got the ****ty connectors on the front by the radiator. Might try cleaning and reconnecting these. Only other thing I could have disturbed is the intake, maybe it has a slight vacuum leak.

Every connector has brittle and broken plastic sheething around it, maybe damp is getting in now and again.

Seems its true about JTS's and their sensitive MCSF failure lights! Its running ok, so not massively worried at the moment...

Fermely strap every brittle connector, i had faults for 6 months and tryed everything to solve them...............untill i drove the car 120 km at 130 km/h and strapped the gas throttle connector. Now 3000 km and and 2 months further................no more any kind off faults