homerhobson 0 Posted September 11, 2008 Im now stumped. The spluttering heap got a new Lambda sensor, and MAF and i checked the wiring back to the plug onto the ECU. The car is still doing the same. Im now scratching my head, what else could be causing the over fueling and i mean over fueling 7 mpg. The car does have a piggy back chip on ( daztec ) is it possible that this might have malfunctioned and be causing the problem. I would also like to here from anyone that has any electrical wiring diagrams for my 93/94 VR6. Iv hunted the net for months and cant find any. The only ones that do come up are always a bit vague, ie they never have all the wires on say from the maf so i cant trace them all to the relevant places and check there not broken. I can remove the piggy back chip either, i thought i could just pull it off and the car would revert back to the original ecu. I think some where along the line the imobilaizer must come into play and as soon as you disconect it the car stops and wont start. Any information on this matter would be greatly apprciated. Thanks Homer James thanks MAF arrived spot on. Quote Share this post Link to post Share on other sites
coolrado 0 Posted September 11, 2008 Have you looked on volkswagen.msk.ru for the wiring diagrams, they are probably as detailed as you will be able to get. Quote Share this post Link to post Share on other sites
g60karmann 0 Posted September 11, 2008 I have a chip fitted to mine that has messed with my mfa mpg reading (3.4mpg most of the time) with that reading you have it would be pretty much neat fuel going in and the car really wouldn't run well at all. What is the car doing? Is it just a dodgy idle, cuts out, etc? Quote Share this post Link to post Share on other sites
homerhobson 0 Posted September 11, 2008 The car ran fine for months. Then all of a sudden it started splutering, i hardly made it home. Iv left it a couple of weeks, but inbetween iv reset some fault codes and its made no difference. Yesterday i changed the Lambda sensor and MAF and it still has made no difference. With the MAF plugged in it the car barely ticks over, even on tick over its lumpy when you set off its lumpy the engine is like its missfiring but it isnt if you catch my drift. On tick over there is black soot coming out of the exhaust, when you set off it makes lots of black smoke but does clear eventually. Its definatly not oil smoke. The car runs dog ruff and is definatly overfueling by a vast amount. Take the MAF off and when cold the car is very difficult to start, you have to keep the revs up, but it will go. when car is warm car starts ok ticks over as well but not a normal rev range its only just and so ticking over. The car runs but when you lift off the throttle it tends to lurch forward as if even though youve removed foot from throttle the ECU is still injecting fuel into barrels, this only happens for a second or two. The MPG goes back up to what it was before all these problems 28 MPG, I cant seen it being the MAF iv got five of the things and surely they are not all broken. Plus when you disconect the MAF whilst engine running the engine dies. Unplugging any other sensors also has the same effect, Temp, Knock, throttle pot. If only some one some where could issue a document on how to test these sensors. Throttle Pot is surely simple to test using a multi meter but i dont know what values to look for. Quote Share this post Link to post Share on other sites
g60karmann 0 Posted September 11, 2008 I'm not sure about the VRs but I had similar issues on my G60 and it turned out to be the idle screw on the throttle body, have you checked this already? Mine just needed tightening. Mine is running slightly rich as well, when I go on long motorway drives I get a huge build up of carbon sot in the exhaust, when I use the car the very next time after such a drive the car struggles not to stall, every time you dip the clutch the revs drop right down and the car has even stalled a couple of times. Plus when you boot it after such a drive clouds of carbon smoke pour out the back, but this goes away quite quickly. Quote Share this post Link to post Share on other sites
MattWilde 10 Posted September 11, 2008 sorry, not too sure about the VR's but have you checked and cleaned all the earth points, and have you checked the whole ignition system? rotor arm, dizzy cap, leads, plugs etc. etc. Quote Share this post Link to post Share on other sites
mattkh 0 Posted September 12, 2008 Hi When was the ISV last cleaned. Quote Share this post Link to post Share on other sites