fiestacosworth Posted May 30, 2018 Report Posted May 30, 2018 Hi. Looking for some info. All was ok Cosworth YB engine TPS was fine. Not been near the car for a month or so. Now have a fault with the tp main reading 4.99v constantly ? And it doesn’t register anything when I press the accelerator I have tried calibration but makes no difference. I’m guess that the TPS is faulty ? Next the car is running extremely lumpy. I have uploaded a log. Can anyone see anything obvious? Thanks. 30 may log.llg Quote
Simon Posted May 30, 2018 Report Posted May 30, 2018 Sounds very much like the TPS channel is either at ground or 5Vs and it is operating on the fault value of 4.99 I would be checking the 3 wires to the TPS for any shorts or broken wires. If you could also connect to the ECU and then save the MAP and post / sent it through it will also have some clues to the TPS issue. Quote
fiestacosworth Posted May 30, 2018 Author Report Posted May 30, 2018 I did have a little look today and didn’t see anything obvious with the wiring. But I will have a better look when I have more time. I will also get the map up aswell Quote
Adamw Posted May 31, 2018 Report Posted May 31, 2018 Another quick test you could do to eliminate some of the possibilities: Go to AN Volt 1 settings and make sure the error low is set to 0V and the error high set to 5V. Then unplug the TPS and take a look at the ANVolt runtime (shown below). If it drops to zero with the TPS unplugged then it suggests it is the sensor that is the problem. If it stays at 4.99V with it unplugged then that would suggest it is a wiring problem. Quote
fiestacosworth Posted May 31, 2018 Author Report Posted May 31, 2018 Hi I actually did as you suggest. And the settings are 0v low error and 5v high error. I had the computer connected with the ignition on and unplugged the TPS and it dropped to 0.02v. That’s what lead me to believe it’s either “stuck” on full throttle inside the sensor. Or it’s shorting straight to earth inside the sensor ? Only confusing thing is that on the throttle graph it shows 0.0% throttle all the time. As you can see on the log. If it was stuck at 5v surely it would be stuck at 100% throttle ? Quote
Adamw Posted May 31, 2018 Report Posted May 31, 2018 6 minutes ago, fiestacosworth said: If it was stuck at 5v surely it would be stuck at 100% throttle ? You said you done a TP calibration though. So your calibration has told the ECU that open voltage = 4.99V and closed voltage = 4.99V. Since that is ambiguous it will fail over to some default value, that seems to be 0% in this case. Assuming no one has swapped the wires around on the TP sensor then your test suggests the TP sensor has failed. fiestacosworth 1 Quote
fiestacosworth Posted May 31, 2018 Author Report Posted May 31, 2018 Yes let me emphasis that is tried to calibrate the sensor as I didn’t know if it had just fallen out of sync. I wired the car and had zero issues. I just wanted my suspicion confirmed that the sensor has failed! So that obviously won’t help with the running Quote
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