Engine low idle!

Hey guys I got the MAF changed on my 1 ltr coil pack engine Micra, It ran perfect for the first day, But this morning it sounded like a diesel! it runs relatively all right when it's cold because it'll idle higher to get the engine warmed up but when it starts to warm up it runs terrible I was wondering if the throttle body is clogged or something along those lines, Any help??
Well the engine management light hasn't come on since it has been changed I mean the car has done just under 42000 miles but I'm thinking there must be something restricting the air flow for the engine not to run right but I don't know I just don't want to spend loads of money on a nissan one :/
Well I tried that before I got the new one and I think it was just as bad to be honest so I'm not sure but I got the obd to it and the only result was mass air flow system but I suppose there isn't a lot of sensors to check.


Club Member
the coilpack k11,s have a stepper motor for idle control eh, and some of them dont have the coolant heating circuit either, ecu reset maybe ?


Club Member
If the old one had a seized waxstat, the throttle would've been stuck open causing fast idle even when warm, and what most ppl tend to do is close up the idle bleed screw to slow it down n mask over the actual problem.

The fix would be to remove that faulty waxstat mechanism, recheck the TPS and IACV is working and within spec, then adjust the warm idle speed with the bleed screw.

If the new TB is a facelift bosch type, which doesn't have the old waxstat, then assuming the IACV is working (fast idles when cold and slows down once warmed) you just have to open/unscrew the idle bleed screw to raise the warm idle speed to 750rpm. Then recheck she fast idles at bout 1400rpm once cold.