Thomas.B Posted August 19, 2011 Share Posted August 19, 2011 Hey guys. If the temp gauge isnt working would it in any way contribute to fuel consumption? Is it linked somehow? I still get crazy bad mileage (125miles to almost full tank!) and ive changed almost everything now... Lambda Sparkplugs All oils and filters Thermostat The emissions test at the MOT went perfect and all values came in fine (with second decat). Running out of options now and its pissing me off that I cant find the problem :/ Quote Link to comment Share on other sites More sharing options...
Scott Posted August 19, 2011 Share Posted August 19, 2011 That is unbelievably low mileage. I can't be of much help as the things you have checked are what I would go with. Have you tried a different ECU in case it's something like that? Quote Link to comment Share on other sites More sharing options...
Konrad Posted August 20, 2011 Share Posted August 20, 2011 Temperature sensor was also changed? Did you use original lambda sensor or universal one? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted August 20, 2011 Share Posted August 20, 2011 The gauge works of its own sensor, the ecu gets water coolant temperature off another. The gauge sensor and gauge have no effect on the map at all. The ecu sensor is the two wire one, the gauge the single wire. Both are by the top house rad elbow. Has it got a stock fuel pressure regulator? Quote Link to comment Share on other sites More sharing options...
Thomas.B Posted August 22, 2011 Author Share Posted August 22, 2011 Konrad: Temp sensor wasnt changed. After market Lambda from sparkplugs, the one recommended from here. Chris: Ok so if there is any damage to the ecu sensor this could be causing it? Do you mean the rad hose? It has the stock FPR, found one of the vacuum hoses to be a little bad and have fixed that also but it didnt help any. Its strange that it gave perfect emissions and drives really well no smoke or anything....its making me crazy! Quote Link to comment Share on other sites More sharing options...
Thomas.B Posted August 22, 2011 Author Share Posted August 22, 2011 Bumping for some help Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted August 22, 2011 Share Posted August 22, 2011 The next thing to do is measure the AFR under a steady load, on a rolling road, and see what it's doing away from idle. Good aftermarket ECU's are just so much better for checking these sorts of issues as you can read and log all parameters in real time. Quote Link to comment Share on other sites More sharing options...
scotty71 Posted August 22, 2011 Share Posted August 22, 2011 leaking fuel tank? Quote Link to comment Share on other sites More sharing options...
scoooby slayer Posted August 22, 2011 Share Posted August 22, 2011 hows that being driven for that mileage ? i get anywhere between 80 - 350 miles to a tank depending how hard i drive it Quote Link to comment Share on other sites More sharing options...
caseys Posted August 22, 2011 Share Posted August 22, 2011 You do use more than 1st gear yeah? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted August 22, 2011 Share Posted August 22, 2011 (edited) Have you checked none of the calipers are stuck? Sounds daft, but it makes a hell of a dent in fuel consumption if a caliper is binding, and the engine's have enough power to mask this sometimes. Worth checking perhaps? Have you got an AFR (Lambda wide band) gauge fitted? If so what does it read cruising and under load? Edited August 22, 2011 by Chris Wilson (see edit history) Quote Link to comment Share on other sites More sharing options...
Thomas.B Posted August 22, 2011 Author Share Posted August 22, 2011 Thanks for the replys m8s. All calipers are in great condition everything rolls fine. I was counting on higher then normal fuel consumption when I bought it as I have had many other high performance cars (far more power then in this one) that used alot... but not this much! And after hearing what others get from theirs its just crazy and pisses me off! Sadly no lambda gauge fitted. But it came out to 1.03 at the MOT during load or if it was at idle. I still have the original lambda and it was just as thirsty before I changed it. After changing all that I have I'm left thinking my ECU might have said goodnight...? Quote Link to comment Share on other sites More sharing options...
Konrad Posted August 22, 2011 Share Posted August 22, 2011 You said temperature sensor wasn't changed - change it maybe? 2 wire one as this is one which ECU is basing it's fuelling at. Quote Link to comment Share on other sites More sharing options...
Thomas.B Posted August 23, 2011 Author Share Posted August 23, 2011 You said temperature sensor wasn't changed - change it maybe? 2 wire one as this is one which ECU is basing it's fuelling at. Ah nice, I'll give it a go! Anyone have the part number? Chris you might have one at home? cheers Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted August 23, 2011 Share Posted August 23, 2011 No need to buy one, just measure the resistance at cold, and warming up, and hot, and compare with Andy Blyth's table : http://www.mkivsupra.net/vbb/showthread.php?238522-2JZ-sensor-resistance! You can check your MAP sensor too, and your air temp sensor. Far quicker to just check the fuelling on a rolling road at various load points and see if you actually HAVE an over fuelling issue though. Quote Link to comment Share on other sites More sharing options...
Nic Posted August 23, 2011 Share Posted August 23, 2011 Did you fit a genuine Toyota oxygen sensor? I ask because I had a number of customers when I was trading who'd initially fitted a generic Ebay O2 sensor and found it made zero/short term difference to fuel consumption. They then fitted a genuine OEM Toyota sensor that made a very obvious difference. Quote Link to comment Share on other sites More sharing options...
Thomas.B Posted August 24, 2011 Author Share Posted August 24, 2011 Chris: I dont know anyone near me that has a rolling road. Will messure the sensors this weekend and start there Nic: nope have one from sparkplugs like so many others on here. And the lambda reading came back ok on the mot... Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted August 24, 2011 Share Posted August 24, 2011 There's a Stack wideband sensor and readout with very basic logging in the for sale section at £200, if I were you I would buy it, fit it, and see what the AFR's are doing. It's a VERY useful tool, with a fair re sale value if you want to sell it on after. It'll save a lot of time if there's no issue with the fuelling. 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.
Note: Your post will require moderator approval before it will be visible.