Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Erratic idle and engine dying

Just in the last two days, my 2012 M3W has started to have an erratic idle and when hot the engine occasionally dies at idle. It is a G56 Stage one tune with a G56 ECU and software, running G56 intake and exhausts. It has always idled far more on the left cylinder than the right from new both before and after (2015) I fitted the G56 kit. It now seems to be idling almost wholly on the left cylinder. My questions are

1) Where do I alter idle speed. It seems to me this is a little low at all times, especially when warm or hot?

2) Is there any way to balance the idle between cylinders?

3) Any thoughts on the recent dying issue.

It has only done around 12,000km since new and around 1500 km since a very thorough going over by M3W services in France, where I had a new fuel pump fitted in a pre-emptive measure, amongst a whole lot of other work, new clutch, hydraulics and release bearing, Bleazey compensator, new RH fuel tank and various other minor things, including a full service.

I cannot run Pro-tune as I don't have a Windows computer and after bricking a Mac by installing Windows emulation software some years ago, I am not going to repeat that.

Wilson

As a quick first look, I would check and clean any crud off the Crank Position Sensor and the Idle Air Control Valve (IAC). These may not be your problem but are quick and easy to do and you never know... It shouldn't be necessary to take apart the IAC but if you do, be warned that bits can fly several metres away! Also, don't be tempted to operate the IAC while not fitted to the car as a similar thing can happen!

I bought a refurbished Windows Laptop for the sole purpose of ProTune.

I have ordered one of Andy's crankshaft position sensor kits and hopefully that will sort the problem. I will also clean the idle air control motor tip. The CPS is one of the few remaining bits of S&S electronics, which have been less than wonderful. In the first four years of the M3W it went through 4 C-E rectifier/charge control units but now 6 years since I fitted an H-D Electra-Glide unit - none! Endless problems with the S&S ECU. None with the G56 unit and so on.

Wilson

My M3W seemed to have caught a cold at one end and a gastric disorder at the other. Two days ago, it was sneezing out of the intake and farting out of its G56 pipes. Turned it off and disconnected power at the master switch. After leaving for a few minutes while I collected my morning croissant from the bakery, turned it back on and it had made a miraculous recovery. I suspect another symptom of the failing crankshaft position sensor but only another 10 days until it goes into winter storage in the showroom of a local classic car restoration garage. I am going to get them to replace the CPS with Andrews replacement kit. I have translated his instructions into French for them. They are also going to bleed the brakes over the winter for me.

BTW have others found the site very tardy over the last few weeks?

Wilson