Talk Morgan Forums Thread Like Summary - Protune2 diagnostics

I have been looking at the S&S Protune 2 manual recently, always handy to have a bit more understanding about how things work. I knew it mentioned about fault code diagnostics being accessible via the "Check Engine Lamp" and/or the speedometer and decided to give it a go. Well to save anyone the time, it doesn't work on the M3W. It looks like we still have to wire up the laptop to access and clear any fault codes.

Just for info, I was getting a P0122, "Throttle position sensor low/short circuit" every few hundred miles on my 40,000 mile 2013 M3W. I tried a bit of contact cleaner and compressed air around it and the voltage at idle was a reasonable 0.38v and seemed stable but it was a very intermittent fault, so not easy to reproduce with the laptop connected. In the end I ordered a replacement TPS from AliExpress for a reasonable £15 or so, including postage from China (thanks for the info Bunny) . It arrived about 10 days later and looks identical to the Magneti Marelli original PF4C/00 item, right down to all the identification markings, almost like that may be where Magneti Marrelli get them from ..... and then add another zero to the price. Since fitting the new TPS I have done a little over 2,000 miles with no EML light. You need a T17 Torx to remove the original "anti tamper" screws, suggest refitting the TPS with M4 x12mm Allen screws and setting the idle voltage at 0.4v then reset the adaptive maps. The idle throttle position should show about 10% and 100% at full throttle with that voltage, it may need a tweak to get the range.

I know it is a bit obvious but S&S ProTune2 is a very useful tool for diagnostics. Even if, like me, you are not that good with the technology and a bit reluctant to try it, it is worth connecting a laptop to the ECU, checking the fault codes and testing the outputs if you have a problem.

A friends M3W engine suddenly went to very rough running and was difficult to start requiring some throttle to get it to start at all, usually you never touch the throttle on starting. On running ProTune2 there were several historic fault codes but no current ones. We cleared them and tried to run it again to see what came up, nothing shown after a few spluttering seconds of running.

You can access less with a locked ECU than you can with an unlocked one, no bad thing normally as that makes it almost impossible to do something wrong. This one was locked. You can still access the “Test Outputs” from the Options Menu. For those that have not used this feature it allows you to check the ignition on both cylinders one at a time, it sparks a plug held against the cylinder for 5 seconds. Fuel injectors can be run independently for 5 seconds, you can hear them or remove them and spray the petrol into a jar to check the spray pattern. The fuel pump can be run for 5 seconds and you can check the pressure with a gauge at the test point at the same time. The Idle Air Control can be motored open and closed. You can also test the Tacho, ECU and Check Engine Lamp. It doesn't test everything, Throttle Position Sensor, Manifold Absolute Pressure, Air Temp and Crank Position are not there but it does check the fuel and sparks are there.

All the tests passed apart from the Idle Air Control Valve that “failed test” consistently, it also sounded rough when motoring. A new Harley Davidson IAC p/n 27628-01A was ordered. Once fitted it all fired up and ran perfectly. I know it's not always that easy but at least you can test a few things easily with ProTune 2.

Thanks, I didn/t know about that - every day is a schoolday