Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Hot and Bothered, and spitting the dummy.

Hello TMers,

Hoping someone can shed some light on an issue that our 1997 4/4(Zetec) is experiencing.

After about 10-15 minutes of normal driving, up a local mountain, on once the car gets to a level surface, it begins to severely stutter or surge(clutch in the thing will rev out, or drop to idle(or stall) then, well act like it had a mind of her own)- To the point the car is un-drivable.

The local ambient temps are hot (ie 32deg C, 70% humidity)-Cairns, Australia.

Car runs(and has done so since we have owned it) between 100-105deg C(problem reveals itself when we are sitting closer to the 105.

Initially I thought maybe a fuel vaporization issue, but the car has been driven in hotter weather, without this arising.

Given its a hot issue, it's proving difficult to fix!
Hoping the brains trust on TM may have some ideas for me to look into?

Cheers
Lachy

Hmmm. I think the first thing I'd do is clean or replace the MAF sensor, and carefully check the air inlet hose for splits or leaks.

When was the fuel filter last changed?

Haha - 4 days ago, at the mechanic :\

I'm reluctant to take it back to him, as its a minimum 5hr fix(1-2hrs drive + fix. Mechanics are about $100-110/hr here) so I may as well do it myself, and through trial and error, get a couple of new bits for Bagheera!)

Those conditions are very similar to having a coil break down. Usually under heat and load conditions, running fine for ages on a light load. Gradually gets worse with time.

Get a cheap code reader if you don't have one already.

Various bits can be effected by heat, coolant temp sensor is another maybe the MAF sensor?

I guess your garage has ruled these out already?

I've had electronic ignition go the same way. OK until hot and then intermittant.

Code reader is a good starter. Heat can cause a myriad of problems, electrical, mechanical, fluid related. The reader might help pinpoint the sources easier. One that can do reading whilst out on a run will enable monitoring at increasing temperature. That, at least will cover possible sensor issues. As temp goes up things expand so leaks might be created, air, fuel, vacuum etc.. Be methodical and thorough checking one system at a time.
Try some of the Ford owners forums too. Even kitcar forums as the Zetec was a popular engine.
Good luck!
Just had a thought.......how are your plug leads? Old? Replace them. Quite a common cause of bad running. I had an escort that spluttered. New leads cured it.

Hm...are you really sure there is no relation between your garage visit, the mechanics work and your issue?
Beside all the profound considerations given here which I can follow easily I would also think about the fact that the fault occurs just after someone has worked on the engine resp. the fuel filter.

My 2013 Sigma-engined 4/4 suffered similar intermittent problems to those you describe "begins to severely stutter or surge(clutch in the thing will rev out, or drop to idle(or stall" in the first few thousand kms of its life. Ambient temperature was not an issue as it happened in summer and winter.

My 4/4 would then run perfectly for hundreds of kms. But after it happened a hundred kms outside Sydney it caused me to lose my sense of humour and the dealer worked on it (still under warranty) until the problem was identified.

Eventually swarf, ferrous and non-ferrous, was found in the fuel tank. The fuel pump had been damaged by the swarf. A clean tank and a new fuel pump solved the problem.

Maybe this isn't your problem, but you may wish to consider it.

Good luck!