stuck Posted January 31, 2012 Share Posted January 31, 2012 Gents, My 4.6 110 is booked in for it's MOT on Friday, the only thing I'm a little worried about is the emissions check (assuming this is carried out at idle speed) even though I have a MOT friendly map as supplied by Nige. Even when warm (IIRC this is defined as 68 degrees within MT) my truck's idle speed is bouncing between 700 & 1200 RPM & occasionally as high as 1400 RPM. The "slow idle speed" is set at 880 RPM so is this just a case that my idle speed is set too low mechanically or am I missing something? Cheers for your patience, Mick. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 31, 2012 Share Posted January 31, 2012 Are you using a PWM idle valve to stabilise it or is it just a case of needing to tweak the idle area of the fuel map to stop it hunting? Quote Link to comment Share on other sites More sharing options...
stuck Posted February 1, 2012 Author Share Posted February 1, 2012 Sorry, yes I'm using a PWM valve. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted February 1, 2012 Share Posted February 1, 2012 Just disable it for the mot, and fix it after the event. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted February 1, 2012 Share Posted February 1, 2012 ^^ Wot he says BLOCK it off with a lump of solid Rod. Set tickover with Allen bolt by top of entry to plenum If it still hunts you have an air leak Nige Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted February 1, 2012 Share Posted February 1, 2012 You can disable it in Megatune/Tunerstudio, just turn off closed loop control and leave on warm up only. If it still hunts you have an air leak Or the idle cells are seriously out of whack. Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted February 1, 2012 Share Posted February 1, 2012 If you just turn it off, the idle valve remains open (a bit). You have to mechanically blank it to completely disable it. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted February 1, 2012 Share Posted February 1, 2012 Yes, but shouldn't be if its the MSQ I built and tuned for Steve Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted February 1, 2012 Share Posted February 1, 2012 If you just turn it off, the idle valve remains open (a bit). You have to mechanically blank it to completely disable it. Yeah I said disable it, not unplug Set the duty cycle to a fixed...25 IIRC is closed, and it won't open or close. Tuning closed loop idle can be a PITA, especially on an auto. Quote Link to comment Share on other sites More sharing options...
bobtail84 Posted February 4, 2012 Share Posted February 4, 2012 Also if you have set the minimum (dc) in the idle control settings to low it will drop too low then bounce up on the spark map. Quote Link to comment Share on other sites More sharing options...
V8 Freak Posted February 5, 2012 Share Posted February 5, 2012 Also assuming O2 correction off at tick over revs !! Quote Link to comment Share on other sites More sharing options...
rusty_wingnut Posted February 6, 2012 Share Posted February 6, 2012 Interested to see this MOT friendly MAP, especially if it's for a truck with cats Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.