Roger Blassberg 0 Posted December 28, 2004 A new problem. The engine idles roughly, and stalls at junctions etc. The fuel consumption has sky-rocketed. The plugs are black and sooty. The exhaust smells very much of a rich mixture. It seems to be running a little cooler than usual during normal driving, although it does get there when in traffic, up to the point of the fans coming on. It all sounds like over-fueling and my first suspect is the blue temperature sender on the thermostat housing. Will that show up on VAG 1551 ? I don't suspect the MAF - disconnection of that causes a very noticeable worsening of the engine running. But how to get at it? The aircon hoses and inlet manifold seem totally to obscure it. Do I need to take off the inlet manifold. I just had the knock sensors replaced and that necessitated all of the manifold coming off and a disproportionately huge bill. I will not be amused if I have to repeat the process. It's worse than working on a Mini !! Best wishes RB Quote Share this post Link to post Share on other sites
dinkus 10 Posted December 28, 2004 I'm not sure if a coolant sensor is going to be the cause of all the problems you describe, it sounds like it's probably more like a lambda sensor than coolant temp. A dead sensor may show up in VAG-COM or 1551, but it might not. Chances are that the sensor will just be throwing bad readings, so will still appear to 'work' according to the ECU. What engine have you got? I know that it's a pig on a VR, but you can replace the coolant sensor from the top even with AC pipes all over the place. You need to remove the metal wire type clip around the sensor first and then it just pulls straight out. Careful not to ping the clip somewhere un-reachable and watch out for hot coolant gushing out ;) I'd also suggest that you flush the coolant system first so you don't get it everywhere when you pull the sensor out. Quote Share this post Link to post Share on other sites
Jim 2 Posted December 28, 2004 Might be worth checking the lamda sensor and all its wiring....? Quote Share this post Link to post Share on other sites
Roger Blassberg 0 Posted January 3, 2005 I found the blue sensor and changed it - disconnect the top hose which enables the a/c hoses to be pushed out of the way, then remove a plastic cover and a small bracket and all is revealed. Only thing is, it turned out to be the lambda probe after all of that. So all is back to normal. Thanks for the advice. Now the chains are starting to tinkle, so it's time for major surgery. Does it ever end?? Best wishes, happy 2005, RB Quote Share this post Link to post Share on other sites