Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing +8 refuses to start

Thanks, Button. Yeah, I am in the US and familar with all you've named above. As I will be up in the NE this coming week I may be able to stop in to Morgan Spares. In the meanwhile, just trying to figure out if the shippers did something they shouldn't have or if it's random bad luck....

As an additional follow-up, tried some starter fluid into the intake with the new relay and the engine fired. Only runs long enough to use up the starter fluid. Tried both resetting and jumping the inertia switch yet again: didn't run. Jumped the pump and it hums nicely and there's pressure in the fuel rail if I check the valve,but won't start with the pumped jumped and running. So spark, no fuel.

Fred, I would like to help, perhaps my 2 cents are completely useless, but perhaps it is good to check all possibilities.
I'm not familiar with the Plus8 engine, but I'm very familiar with the kind of symptom (which can be caused by many reasons of course). If your engine fires up using starter fluid but soon afterwards dies, I had the same symptom with a Porsche 928S from 1983. The culprit was the "Temp sensor II" which tells the system to enrich the fuel mix for cold start. We had looked for more than months before we found the reason for the fault.
May be the Rover engine also uses such kind of temp sensor which is responsible for cold start fuel enrichment? At least the smptoms with the 928 were exactly the same, only running with starter fluid as long the temp sensor 2 was broken.

Fred, I cannot remember if you've done this but I think it's time to put an ODBII reader on it and see what error codes are on the ECU, as the previous post says it's probably a sensor causing the fuelling issues.

Injectors may not be opening, as part of the fueling, the pump would cut out when the fuel rail is up to pressure, if the injectors don't open then that'd be more or less instant. This is something else that you could add to the fueling conundrum!

Adrian - to note an earlier point, neither a relatively high end OBDII reader nor RSW GEMS-specific software can communicate with the ECU currently (link error). One concern was that the multifunction relay, which powers both the pump and the ECU, was bad, but the problem persists with a brand-new relay. The pump sems able to function if it gets power, and the engine seems to have spark if it gets a combustible mixture. I would think a dead ECU would explain both the pump and the inability to communicate via OBD... BUT there'd be no spark if the ECU was dead?? And, to Milligoon's point, ECU also operates the injectors...

Sorry Fred I recall that now. As you say your getting a spark/combustion when engine spins and you have supplied fuel by spraying it down its inlet manifold, but if I remember the Gems correctly the spark is produced through the distrubutor circuit and so if the engine spins up if this side of things is in tact then you will get a spark. This appears to be what is happening to your car. The ECU in the GEMs monitors the air flow (MAF sensor), the throttle position (step potentiometer on the throttle body) and exhaust gases(lambda sensors) and probably engine temperature. A pretty simple ECU compared to modern setups, it then uses these variables in conjunction with the low tension (spark) to open the injectors and fuel the car.

So from my hardware/software testing experience I would say it looks as if the ECU is the issue, especially if your getting link errors, obviously the easy way to prove this is swap it out with a known good and try the car. Hope this helps,

My T16 had horrible ECU issues. I swapped it & it worked but that then started to fail. It does sound like it is worth a go.

Remove battery terminals

Disconnect ECU give both the plugs and the ECU sockets a good wash out with contact cleaner - allow to dry thoroughly (as its conductive in its wet state) then refit and see if any change.

You may simply be experiencing some oxidation in the contacts?

I wonder if You can swap a Gems ECU. Not sure about Morgan but in a Rover the ECU has security that will not allow another ECU. I have a GEMS EFI that I wanted to install in My +8 Bitsa. But I will need to use an aftermarket ECU. At the moment I was going to use "MegaSquirt". But after Collins message about "cold start" I wonder if MS has the circuitry to run a GEMS.

Better check, I am a light weight when it comes to EFI.

Button
Seattle