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Hi All
Long time viewer of the forum/wiki but first time poster.
2014 Jimny gen 3
1.3l vvt 57000 odd kms
Ever since fitting a custom snorkel and a few versions of an airbox to suit I have had trouble with rough idling and idling at all with cold starts.
While the truck was used exclusively for 4wd club use this never caused too much of a problem, other than a check engine light of which I would clear from time to time with a obd2 tool, but I have recently retired the Jimny from club use and rebuilt it back to a respectable road car and my wife is now using it as her daily.
The rough idling and keeping running when cold was a bit much for her as she starts work pretty early so I was tinkering around with it while it was running and disconnected the MAF sensor and straight away it started idling perfectly, a little high perhaps at 1100 odd rpm, and upon a test drive the car seemed to be going a lot better and had noticeably more poke. So I left MAF disconnected and happy days.
This was fine and wifey was happy for a week or so before she started to notice it was using quite a bit more fuel, so I stopped into a local wreckers and picked up two second hand MAF sensors and a can of MAF cleaner and tried to install them.
When any of the 3 MAF sensors are installed and connected the car goes back to farting and spluttering and wont idle.
So?
Bad luck and I brought 2 dead MAF sensors?
I wrecked the 2 replacement units spraying them all over with CRC MAF cleaner spray?
Or something else?
It might be something else other than the MAF sensor. With the sensor removed your fast idle might be masking another problem, perhaps the IAC valve in the throttle body or perhaps a small vacuum leak.
Did it use excessive fuel with the MAF sensor installed the same as with it removed? It’s possible that it didn’t, but I would have thought that the O2 sensors would have brought the mixture under control with or without the MAF.
As I understand it it throttle position and MAF (with ecu map) are the course adjustment, with the fist O2 sensor providing the fine control.
Robin
2020 blue SZ5 (one of the last to be registered in the UK)
Ex 2011 Blue Jimny SZ4
Northumberland Jimny Blog
