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Re: Engine Misfire, now won't start planenut #841146 10/04/26 08:55 PM
Joined: Mar 2026 Posts: 13 Fort Worth, Texas N Nukebug OP New to Talk Morgan
OP Nukebug New to Talk Morgan N Joined: Mar 2026 Posts: 13 Fort Worth, Texas	planenut, yes, thank you, I am aware, and I already have the instructions printed out. I also used them for a parts list for ordering the correct parts! 2013 Morgan 3W

Re: Engine Misfire, now won't start Nukebug #841147 10/04/26 09:05 PM
Joined: Mar 2026 Posts: 13 Fort Worth, Texas N Nukebug OP New to Talk Morgan
OP Nukebug New to Talk Morgan N Joined: Mar 2026 Posts: 13 Fort Worth, Texas	Originally Posted by Nukebug Hello Everyone, Longtime listener, first-time caller. First let me say that I have admired the M3W for probably 15 years, and I finally pulled the trigger and bought one from auction (thanks BAT!) and I accepted delivery of my 2013 British Racing Green beauty just over a week ago (Monday). LOVE IT! It is everything that I had hoped for, and my lovely wife concurs. We were out for a nice run this last weekend, enjoying the absolutely perfect driving weather this last Sunday around DFW. I was coming onto the highway, accelerating on the on-ramp, when I heard a pop from the engine and lost power. I was able to keep running, albeit with an odd tapping noise, to get to my son's house. Low power, and I felt like only one cylinder was firing (yes, still enough horses to run on one cylinder!). This was confirmed when I reached his house and shut down, the left (driver's side) exhaust was only hot, while the right (passenger side) was scalding. I let it sit for a bit, but it would not start at all when it was cooled down completely. It turns over. I checked for spark from both plugs and confirmed spark. I checked for fuel pressure at the Schrader valve on the fuel line with a tire gauge and it maxed out at 50 psi. I had it towed home (flat bed). I have since checked the timing belt - solid, no miscellaneous bits. I hooked up a laptop using the S&S Pro Tune II v4.0, and the only error codes are P0170 Front Adaptive Maxed Out and P0173 Rear Adaptive Maxed Out. When the key is turned on, fuel pump whines. I have not removed or checked the fuel filter. I am not sure where to go from here? How do I verify fuel is getting in the cylinders or check the EFI? ANY and all ideas or help are appreciated! Oh! on a side note, the left rear signal light works sometimes, and sometimes it does not. Also, If the headlights are on when I turn off the motor, the left front headlight will stay on, but at half the brightness of normal. Is this normal? Connected? one of the endearing oddities of owning a Morgan? Thanks! Ok, so I figured out one of my issues with the headlights - I was not aware that the headlights have a DRL in them! the left one works, whilst the right headlight DRL does not! So I have ordered new, brighter headlights to replace the old ones. 2013 Morgan 3W

Re: Engine Misfire, now won't start Nukebug #841770 18/04/26 11:53 PM
Joined: Mar 2026 Posts: 13 Fort Worth, Texas N Nukebug OP New to Talk Morgan
OP Nukebug New to Talk Morgan N Joined: Mar 2026 Posts: 13 Fort Worth, Texas	OK, I am back. I replaced the fuel pump and fuel filter as per the excellent instructions provided by the forum. No Joy. It will initially act like it wants to start (random pop!) and then just the starter turning over the engine. I am really disappointed that the fuel pump swap did not do anything --- any new thoughts? Could it be as simple as 'bad gas'? I did fill up just shortly before this all happened. Shortly is about 30 miles of driving. I will also mention that I probably overfilled as the gauge was reading only 20%, and yup, I fell for it. 2013 Morgan 3W

Re: Engine Misfire, now won't start Nukebug #841771 19/04/26 12:37 AM
Joined: Dec 2020 Posts: 106 Likes: 7 Orange County, CA S Socalm3w L - Learner Plates On
Socalm3w L - Learner Plates On S Joined: Dec 2020 Posts: 106 Likes: 7 Orange County, CA	1.Check if mass airflow sensor is ok. While your described symptom of only one cyclinder acting up would rule out issues with the sensor, the codes you have indicate both cylinders apoear affected. On most cars, if you simply unplug the sensor the ECU reverts to a base map and engine will run if only sensor was the issue. Not sure if our engine does this but worth a try. 2. Check if crank sensor works. Unlikely the issue, but an easy check on cars at least. While engine is cranking look at tachometer. It should show revs while cranking. I don’t know if the Morgan does this normally though. My engine is out at the moment for centa roller replacement so I can’t confirm. Maybe another member can? 3. Check timing. Confirm everything is in time and the belt didn’t skip a tooth. 4. Check if fuel injectors are indeed working. Easy way but not precise: Don’t know if pro tune allows, but a scan tool on many cars allows you to control individual injectors. Pressurize the fuel system by activating fuel pump with protune (if it allows) and read fuel pressure. Then individually activate each fuel injector and look at fuel pressure drop when doing so. If it drops you know the injectors are working somewhat. If you see a difference in pressure drop between injectors, you may have identified a bad one. Another very crude way is to try to start the engine and then pull spark plugs and smell to see if they smell like gas. If no smell of gas then likely injector isn’t opening. Precise way: If you’re comfortable and have a scope, you could also look at injector voltage waveforms to confirm ECU is sending a pulse to command the injectors and the injector is opening/closing correctly. 5. Check compression and if fine then do a leak down check. Last edited by Socalm3w; 19/04/26 12:43 AM.

Re: Engine Misfire, now won't start Socalm3w #841772 19/04/26 06:14 AM
Joined: Jul 2013 Posts: 3,732 Likes: 79 West Sussex, UK Chris99 Talk Morgan Addict
Chris99 Talk Morgan Addict Joined: Jul 2013 Posts: 3,732 Likes: 79 West Sussex, UK	Originally Posted by Socalm3w On most cars, if you simply unplug the sensor the ECU reverts to a base map and engine will run if only sensor was the issue. Not sure if our engine does this but worth a try. For the M3W simply disconnect the battery for about 10 mins (I do 20 to be sure) and that will clear the adaptive mapping and revert to the base tune. Red Leader

Re: Engine Misfire, now won't start Nukebug #841775 19/04/26 06:46 AM
Joined: Nov 2013 Posts: 786 Likes: 18 exagone france G GLLOQ Talk Morgan Regular
GLLOQ Talk Morgan Regular G Joined: Nov 2013 Posts: 786 Likes: 18 exagone france	The last time my engine suddenly lost power with a bling bling noise, I managed to get home with one engine cylinder (about 10 km): it was the broken valve spring retainer cup, it's easy to check.

Re: Engine Misfire, now won't start Nukebug #841778 19/04/26 07:33 AM
Joined: Jun 2012 Posts: 2,242 Likes: 72 United Kingdom, Lincolnshire planenut Talk Morgan Expert
planenut Talk Morgan Expert Joined: Jun 2012 Posts: 2,242 Likes: 72 United Kingdom, Lincolnshire	It sounds like two issues, the fault codes and 50 psi fuel pressure certainly indicate a problem with the fuel pump but I would agree with GLLOQ that a check of the valve springs may be a good idea.

Re: Engine Misfire, now won't start Nukebug #841802 19/04/26 04:22 PM
Joined: Nov 2020 Posts: 51 Likes: 2 2 2017 Betty Just Getting Started
2017 Betty Just Getting Started 2 Joined: Nov 2020 Posts: 51 Likes: 2	Hi Chris99 I have a 2017 and would like to but on your list if you order more TSM. thanks Tim k9us73@gmail.com USA

Re: Engine Misfire, now won't start Chris99 #841808 19/04/26 06:03 PM
Joined: Dec 2020 Posts: 106 Likes: 7 Orange County, CA S Socalm3w L - Learner Plates On
Socalm3w L - Learner Plates On S Joined: Dec 2020 Posts: 106 Likes: 7 Orange County, CA	Originally Posted by Chris99 Originally Posted by Socalm3w On most cars, if you simply unplug the sensor the ECU reverts to a base map and engine will run if only sensor was the issue. Not sure if our engine does this but worth a try. For the M3W simply disconnect the battery for about 10 mins (I do 20 to be sure) and that will clear the adaptive mapping and revert to the base tune. This isn’t the same thing. I didn’t explain it well. When unplugging the sensor, most cars will run off of a map that ignores input from the mass airflow sensor and relies on inputs from other sensors. This is different than running off of the default fuel map as described.

Re: Engine Misfire, now won't start Nukebug #841809 19/04/26 06:09 PM
Joined: Jun 2012 Posts: 2,242 Likes: 72 United Kingdom, Lincolnshire planenut Talk Morgan Expert
planenut Talk Morgan Expert Joined: Jun 2012 Posts: 2,242 Likes: 72 United Kingdom, Lincolnshire	If you are checking the compression, remember that the X-Wedge has "easy start" cams that lift the exhaust cams at low "start' rpm to ease starting load. You will need to back off the exhaust rockers to get realistic readings with a standard compression tester or use a differential pressure check kit.

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