acox99 74 1 Cars Posted June 18, 2008 Right basically i've just done a bottom end rebuild on a late 2ltr mi, it runs perfect until it's put underload ie when i try to pull away or move it. It just stalls, if it doesn't then it just keeps hunting for idle until it just stops. i restart it and it idles perfect again until load again. anyone got any ideas? i checked most things all i could think was MAP sensor but thats built into the ECU so not sure how to test it, and if thats gone it could be a right a*se. thanks in advance Alan Share this post Link to post Share on other sites
nick 3 Posted June 18, 2008 Sounds more like the AFM to me. With the throttle shut, the idle circuit takes over, but when you touch the throttle it comes off the idle circuit and the AFM etc.. takes over. Nick Share this post Link to post Share on other sites
welshpug 1,657 Posted June 18, 2008 Sounds more like the AFM to me. With the throttle shut, the idle circuit takes over, but when you touch the throttle it comes off the idle circuit and the AFM etc.. takes over. Nick 2.0 Mi doesn't have an AFM. check that the MAP sensor pipe is plugged in securely and that there arent any leaks in the intake manifold, there are a few takeoffs with blanks that arent always secure. Share this post Link to post Share on other sites
acox99 74 1 Cars Posted June 18, 2008 2.0 Mi doesn't have an AFM. check that the MAP sensor pipe is plugged in securely and that there arent any leaks in the intake manifold, there are a few takeoffs with blanks that arent always secure. yep no afm, and i have checked the pipes, all fine and no leaks anywhere i can find. i just seems really bizarre as everything was working fine. Share this post Link to post Share on other sites
welshpug 1,657 Posted June 18, 2008 probably an idle valve problem then if the MAP is fine, certainly sounds like an Air leak more than anything. Share this post Link to post Share on other sites
nick 3 Posted June 19, 2008 Probably not the AFM then..... Nick Share this post Link to post Share on other sites
brumster 135 1 Cars Posted June 19, 2008 Mechanic mate showed me a great trick for spotting air leaks into the system; spray cold start (or WD40 if you don't have any) around general areas of the inlet system and if there's a leak, it'll suck it in and you'll notice the idling increase. Helped me spot a leaking gasket once Share this post Link to post Share on other sites
Stu 18 Posted June 19, 2008 Sounds like the TPS to me.. Share this post Link to post Share on other sites
acox99 74 1 Cars Posted June 24, 2008 Found the problem today, turns out i've been a total cock and missed one of the 3 earth leads when bolting them down. earthed the lead and problem solve now runs perfect! i feel such a tit but atleast its nothing major! Share this post Link to post Share on other sites
Ethos 0 Posted June 25, 2008 (edited) Nice one, glad to hear you got it fixed! Edited June 25, 2008 by Ethos Share this post Link to post Share on other sites
