Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Severe engine stuttering

I've had this car since 2012 and while it does act up if I fill the tanks too high, that usually clears up in 9 or 10 miles. Filled it a month or so ago and the car sat due to life... Fired it up today and the stuttering was severe in that I genuinely worried about the drive train taking a hit. The engine would come to a complete stop but then resume. If I was at idle, it would just quit. Trouble starting up as well after that. For a few moments it ran quite smoothly and 'normal' but then it all started back up again.

1. Fuel pump? This is the second one. The first one just died suddenly. I don't think it's that.
2. Engine mapping glitch?

I'm scratching my head on this one.

Check the fuel pump pressure at the Schrader valve on the top of the engine, should be 58psi with the engine running.

Highly unlikely the map changed whilst it was sat doing nothing.

My first thought would be fuel pump as Roger says or it could just be old fuel (modern fuel doesn't keep long at all).

Is the engine light on? Check with Protune it could be the throttle position sensor.

Oh well. I don't have Windows anything in this household, so I can't really plug anything into the beast to talk with it. Will be taking it to Morgan Motors of New England in a week to decipher this latest incident. Dang. Weather has turned really sweet of late and I hate to miss riding opportunities!

It’s worth getting a cheap Windows PC off eBay or similar just to run Protune.

I walked away ((Ran!) from windoze over 20 years ago due to being just too damn tired of hacking the Registry to make it do what I wanted it to do and having to reformat the machines every year or so because they got corrupted or just weird. Went to Apple and converted the windoze boxes to Linux and never went back.

Now Windows is just too new and different and I really don't have the energy or desire to learn another new OS. Happy with Apple and it does what I want, reliably and without issue.

You’ll be pleased to know Win10/11 is much more reliable now - I only rarely have to reach for regedit!
Agree with Chris - an old work laptop or $180 Amazon special might be worth the investment. Especially if you don’t like the idea of a pricey Apple device in a garage!

PS: UTM for Mac is a “free” / open source means of running Win on Mac but will only virtualise Win for ARM on M chip Macs ie recent ones - UTM has an emulator mode for Win on x86 but haven’t tried it… (nb: it’s “free” in that you don’t need to pay for the VM capability, but if you activate the Win license you still need a Win license code). I suspect Protune will dislike running on Win for ARM.

If the fuel pump checks out OK (do you have the decent Walbro one?) then another bit to check is the Throttle Position Sensor - it seems that dirt or wear on the track can give rise to all sorts of rough running - we have experienced this.

Apart from run Protune

Real quick update...

Having perused the Internet of Things, I ran into a quick fix for the Throttle Position Sensor which involved disconnecting the battery for at least five minutes then hooking it back up again. The Check Engine light behaved and the car started right up and maintained a smooth idle. Am now going to take it for a drive.

As an aside, the Check Engine light had been on for this series of events but as I had been driving it in bright sunlight, it was practically invisible. My bad for missing this symptom.

We shall see... Stay tuned for further adventures!