jrgibb72 Posted March 25, 2018 Share Posted March 25, 2018 Hi all,RoadSport 150 on ITBs been out today, about an hour and a half, stopped for 30 mins at a cafe, then headed back. After covering about 80 mile the car would’nt drop below 3500 revs. Turned off the engine at lights, re started, the same. Clutch in and a few good blips of the throttle, the same.Pulled over, turned off key out, tried putting key in position 2 and press the throttle through full travel a few times, turned on the same (that key 2 thing is the TPS reset on the Elise, just trying something). Stopped, lid off pushed the throttle linkage in the ITBs a few times and this sorted it for a few miles when it started again. Got home same procedure lid off pushed the throttle linkage a few times through full travel and wiggled the TPS wire and it tick over ok again - in the garage safely.Any thoughts?? Thanks J Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 25, 2018 Member Share Posted March 25, 2018 i think that each of the components (pedal, cable, throttle) can get sticky and you need to look and disconnect until you've worked out which it is.There's a known specific problem with some throttle bodies sticking because something is overtightened but I can't remember which are affected or the details: check the *archives or wait for an expert...Jonathan* ± "' :-) Link to comment Share on other sites More sharing options...
SM25T Posted March 25, 2018 Share Posted March 25, 2018 Jonathan .... you are thinking of the plastic throttle body with a single butterfly. Overtightening the jubilee clip on the air filter can trap the butterfly. I would disconnect the cable both ends and check free movement of pedal ... inner cable and throttle body spindle. Also check balance of throttle bodies (do they work in pairs ?). Link to comment Share on other sites More sharing options...
SM25T Posted March 25, 2018 Share Posted March 25, 2018 Also check for air leaks in the vacuum hoses connected to the inlet. Tiniest leak will allow revs to increase rapidly. Link to comment Share on other sites More sharing options...
jrgibb72 Posted March 25, 2018 Author Share Posted March 25, 2018 Thanks guys - plenty to check and work on!J Link to comment Share on other sites More sharing options...
ChrisC Posted March 26, 2018 Share Posted March 26, 2018 Hi Jason Is it a Sigma 150? (if not you can disregard all that I have posted below) The 150 should not have an air hose connected to the inlet - this was removed over the many version release by CC. The final version had the MAP sensor open to the atmosphere, however a little hose on it to stop a direct hit from water killing the sensor isn't a bad shout. The Sigma 150 TPS doesn't have a reset via the ECU, it can only be set manually with access to the MBE Easymap software. Even setting it with a multimeter does not guarantee that is the reading the ECU is seeing. The Sigma 150 is very sensitive to this setting and a good ITB balance. Check the mechanical stuff first, cable, butterflys etc. then find someone with access to the diagnostic leads you need to see what the ECU is doing. Sensors do fail on Sigmas and the results can be strange. again this is all 150 Sigma related, just in case its a K. Chris. Link to comment Share on other sites More sharing options...
ChrisC Posted March 26, 2018 Share Posted March 26, 2018 Just found a picture of your car and rough location, your not that far from me and it looks (from the exhaust exit) like a Sigma, so willing to help diagnose the problem. PM me if you want my help. Link to comment Share on other sites More sharing options...
jrgibb72 Posted March 26, 2018 Author Share Posted March 26, 2018 Chris - you helped me setup my car remember :-) The balance was out not on the pairs but between the front two TB's, the TPS was at the right voltage - since your setup the car is still starting up first pull and ticking over nicely. Will be checking all the physical bits first, this all happened after a long run with car running for 2 hours plus, may be something sticking as everything was probably a little hotter than normal after such a long run. Going to start at the throttle pedal and work forward - thanks J Link to comment Share on other sites More sharing options...
ChrisC Posted March 26, 2018 Share Posted March 26, 2018 How could I forget, yours was the only "early" 150 design I have ever seen, with the air bled screws under the fuel rail. Mechanical is my guess, but each time you stopped and started again you will have reset the lambda sensor warm up sequence. It's possible the lambda sensor has gone, they are not known for their reliability. Link to comment Share on other sites More sharing options...
jrgibb72 Posted March 26, 2018 Author Share Posted March 26, 2018 Thanks Chris!!! Link to comment Share on other sites More sharing options...
jrgibb72 Posted March 26, 2018 Author Share Posted March 26, 2018 Ha ha - first item on the list to check, the lambda sensor, loose as in 3/4 turn before it was finger tight - if that was drawing air would the bad signal to the ECU cause it to rev high like that?? J Link to comment Share on other sites More sharing options...
ChrisC Posted March 26, 2018 Share Posted March 26, 2018 Can’t help, but not sure how much adjustment the lambda sensor can make. Best give it a test. Don’t forget the lambda adjustment does not take place until the coolant is 60C. Link to comment Share on other sites More sharing options...
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