Hudson93 Posted December 14, 2013 Report Share Posted December 14, 2013 Hello my first thread on this forum!So recently just purchased my new lupo and noticed it drank alot of fuel at idle (about quarter of a tank it i was stationary for around 30-45mins!borrowed a friends diagnostic lead and software and"no signal to lambda" "coolant temp sensor"(easily done!)explains the juicyness!so looked under the car and the lambda is there but all the wires have been broken! guessing the road ripped it off(its VERY low)so i have enough wire on the lambda to repair it with some repair cable however where in the engine bay is the plug for the lambda sensor? has a 4 branch manifold and a decat but the lambda is mounted a fair way back like on the centre section...is there a precat and post cat?or because its an early model does it only have one?if someone could be so kind to answer my questions it would be much appreciated Lee Quote Link to comment Share on other sites More sharing options...
EvoRox Posted December 14, 2013 Report Share Posted December 14, 2013 (edited) The 16 valve engines got a precat included in the manifold, it's directly inside where the 4 original manifold channels end into.There sits the first lambda its plug got only a 10 inch wire and is located in a bracket on down end of manifold heat plate , the second cat/ main cat is the one underneath your car. Edited December 14, 2013 by EvoRox Quote Link to comment Share on other sites More sharing options...
Bigplum Posted December 14, 2013 Report Share Posted December 14, 2013 (edited) I would have thought your engine light would have been on with lambda faults, does everything that should light up and go out on the dash?The ecu should default to base settings if the lambda reading goes wrong , not sure why it would drink excessive fuel .What colour are the plugs ? Edited December 14, 2013 by Bigplum Quote Link to comment Share on other sites More sharing options...
Hudson93 Posted December 15, 2013 Author Report Share Posted December 15, 2013 Well the cheeky sod took the bulb out Ok i think i know what plug is for the precat , Wheres the postcat plug? At the back? Im guessing il need to drill into the manifold and fit a lambda then As i have a 4 branch which doesnt appear to have a hole for it The plugs i havent checked but im guessing they will be blackThe engine thinks its cold all the time = more fuelDoesnt know the oxygen readings of gases =its confused! Hence the poor fuel consumption!Other than that i hava a low voltage error code to ecu Injector 1 and 2 but the wire had been repaired so he may not have cleared the codes afte he fixed it....they work fine so must be the case So the pre cat is underneath battery tray area which ive found just the other one now any ideas? Quote Link to comment Share on other sites More sharing options...
Bigplum Posted December 15, 2013 Report Share Posted December 15, 2013 (edited) Post cat lambda fits just after the cat , it reads the difference in oxygen from the pre cat one and checks the cat is working.Are you sure there is not a blanking plug in the manifold?The wire connections are special high temperature ones , Vw sell a short length of repair wiring Good reading here. http://www.picoauto.com/applications/lambda-sensor.htmlPretty sure I've seen weld on lambda bosses on eBay or go to a scrappy and chop one out Edited December 15, 2013 by Bigplum Quote Link to comment Share on other sites More sharing options...
Hudson93 Posted December 15, 2013 Author Report Share Posted December 15, 2013 the post cat one is fitted just the wires ripped out , just need to know what plug the wires go to its a decat alsoand just checked and theres nooo blanking pluglooks like il have to weld one in il post a picture of the manifold to make it easyier? Quote Link to comment Share on other sites More sharing options...
Bigplum Posted December 15, 2013 Report Share Posted December 15, 2013 (edited) There should be a socket nearby , often inside a plastic box or do you mean the wires have just pulled out the plug? ,Until both are connected you won't get any real sense out of ecu anyway, but it would either use base/ default settings or go into limp mode . Is the manifold aftermarket ? I have a feeling the lambda goes in the downpipe ( that goes to the cat) , so if its decat'd the sensors won't play anyway, what year is the car ? It'll be a swine to get a mot on it without a cat. The joys of buying a modified car Edited December 15, 2013 by Bigplum Quote Link to comment Share on other sites More sharing options...
Hudson93 Posted December 15, 2013 Author Report Share Posted December 15, 2013 there is about 10cm of wire coming from the lambda probe but need to find the socket they go to il have to have a look soon , its a bugger even getting it on stands , (my jack isnt low enough and have to drive it onto wood or similar ) i do believe its aftermarket or off an older car with the same stud pattern with the cat underneath , no lambda boss on downpipe either!) its a Vreg so very early model , and i know some friendly mot garages..........i know right!! Quote Link to comment Share on other sites More sharing options...
TNT93 Posted December 19, 2013 Report Share Posted December 19, 2013 Just fyi I have a 1999 1.4s and it has a 4 branch manifold with no lambda, only one at the cat in the centre of the car, I also have no engine management light, this is how the early models were I believe, don't know if it helps or not.Tom Quote Link to comment Share on other sites More sharing options...
Bigplum Posted December 20, 2013 Report Share Posted December 20, 2013 Does your engine light come on with the ignition then go out when it's running? 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.