Bean 0 Posted February 20, 2004 Hi i think my vr6 is running a bit rich the only way i know to sort this out is buy having it tuned. The only problem is is that because i have a CAT the guy at the tunning place told me it cant be done?! :?: Is this true? What can i do to get this problem sorted? Cheers Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 20, 2004 Yep your tuner is correct. The lambda probe does the engine tuning for you until approx 4000-4500 rpm or WOT and then fuelling is chucked in via the TPS, ignoring the lambda. First thing to check is the probe then.....you need to get a high impedance meter on the probe whilst the engine is running and hot. Black meter lead goes to earth, red lead pokes into the white wire on the probe's plug, which is on the rear engine mount. You're looking for a constant voltage fluctuation of 0.1 to 0.9V. If it's stuck at 0.45V, it's dead. Could also be a MAF sensor fault. K Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 20, 2004 Moved to problems Quote Share this post Link to post Share on other sites
Bean 0 Posted February 20, 2004 Ok cheers i will try and get hold of a high impedance meter and give it a go! How do i check the MAF sensor? Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 20, 2004 I've got a lambda probe for sale in the Parts section if you need one. To check the MAF....hmmm....bit of a grey area that one. Normally pulling the plug off with the engine running is a good indicator..... if the engine stalls and dies, it's OK. If no change in engine note, chances are the ECU has bypassed it, meaning it's gone bad. VAG-COM won't tell you anything pertinent about MAFs unfortunately, except for short circtuit conditions or a complete abscence of a signal. 9 x out of 10, MAFs operate out of range which the ECU won't register. K Quote Share this post Link to post Share on other sites
Bean 0 Posted February 20, 2004 ok the other problem is i have ordered a bently manual off e-bay bt it isn't hear yet so i don't really know what half this stuff looks like or where it is! What does MAF stand for? (is there some sort of glossery somewhere) Is there someone that can sell me a copy of the bently maunal on cd cheap cos i want bothe anyway! :D Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 20, 2004 Mass Air Flow sensor It calculates air volume by air passing over a heated platinum wire. The colder the wire gets, the lower the resistance and the more fuel you get. K Quote Share this post Link to post Share on other sites
Bean 0 Posted February 20, 2004 ahh now a lot of the post i have read around this subject make sense!!!!!! :wink: cheers!!! Quote Share this post Link to post Share on other sites
Bean 0 Posted February 23, 2004 I take it that this is the MAF sensor?! (see attachment) When i take it off the engin doesn't stall it ound like it is running out of fuel is this what is is supost to do? :? Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted February 23, 2004 Can't see any attachment mate? The engine may not stall but if it coughs and splutters, that's a good sign the MAF is OK. Quote Share this post Link to post Share on other sites
