And the saga continues …..

Now checked and confirmed fuel pressure appears to be OK with just over 30psi showing when the problem manifests itself. A bit of fluctuation occurs (as a result of having removed the RH FPR), which is to be expected. So RH FPR, will be going back on once the problem is found.

So I think I can now rule out that there is nothing wrong with the fuel delivery and focus more on the spark! But what exactly? Maybe the amplifiers? But all this is now just guesses focusing on what hasn’t been replaced. Need a more scientific approach to finding the source of the problem. 🤔

 

I have just changed my B-bank FPR. It was the same, 60229. I believe it was the original part as the engine is from 89 and I have full service records since the engine was mounted in my XJ-S in 96.

 

Has this thread delved into distributor issues? Does the vacuum advance work properly and are there issues with wear that could affect running over 3000? They don’t seem that simple inside.

 

Actually, the distributors are really simple. No mechanical or vacuum advance. Only a rotor button. All vacuum advance and timing is managed by the ECU.

 

Ah- well scratch that then. My 89 has a vacuum advance on the distributor. But it is Lucas.

 

Well, it has been some months now and I thought I might provide my final update on this erratic issue I’ve been experiencing with a severe miss after a few kilometres of running.
For those that have been following and contributed to resolving my problem to date you’ll be aware of the extensive list of items that have been addressed and fixed. All of which have no doubt contributed to resolving and improving the operation and usability of the car, but never resolved the underlying problem. So, what was the issue?
It was a few things actually and not just one item, hence the difficulty in tracing the problem.

1. Air temp sender
2. ignition Modules
3. Crank Position Sensor

And with all that, it is now running like clockwork and ready to attend a Jaguar XJS gathering this coming weekend with some 40 XJS’s expected to converge. A round trip of of approximately 900kms. Fingers crossed.

Thanks all for your input.

 

That’s awesome you got it sorted. Thanks for following up with the details on what it was. Beautiful car, glad you can enjoy it now.