Hi,
I just got my S1 XJ6 back from the shop from a full rear deferential rebuild.

• Unfortunately the car is no longer idling.
  • It's super lumpy
  • Misfiring
  • Hesitating on acceleration,
  • Zero acceleration on incline.
  • The choke doesn't seem to be working now either.

From reading the forum I spent today changing:

• Ignition coil
• Sparks plugs
• Fuel Filter
• Fuel pressure regulator
• Checked hoses for vacuum leaks

Any direction super appreciated. I'm trying find a knowledgeable Jag store in Portland to tow to, no luck yet.



Thanks
Minder

 

You have covered the basics, BUT, HT leads, all 7 would be my next "to do".

Relationship to the rear end, NONE, but someone has fiddled, and finding that is the time thing.

 

Thanks @Grant Francis I'll check out the plug wires.
Totally agree, it's going to be a test in patience & perseverance :-)

 

Fill the beer fridge, works very time.

 

Forgot, it happens.

I will assume you still have Contact Points Ignition??

If so, replace the Condensor inside the distributor. They be little, but can reek havoc.

 

Did the car spend time outside the shop in the rain?
Check for water in the fuel. Those filler caps can often leak in heavy rain esp. if the drain tubes are blocked.
Just a thought, as I have experienced the same symptoms.

 

Thanks, I'll check the distributor.

 

Thanks @redtriangle I had not thought of that, Ill look into it.
I'm always having to clean out those drainage holes :-)

 

Not sue if it is relevant, but I'm getting smoke puffing out of the circled pipe when firing up the car.
I replaced a kinked hose off of the fuel rail to the air box, but it did not help :-(

 

Well, it seems to me your anti-smog/pollution control set up is causing problems.
You don't need all that crap strangulating your engine.
I would remove it all, and chuck it. Severely.

 

Thanks. Good shout. I think I found a mechanic familiar with the Jag.
Getting it towed there on Thursday.

 

My S1 did this a few years ago. Ended up putting in electronic ignition. Never a problem after that.

 

The circle cover two pipes: the air injection pipe and an air conditioning pipe. Neither should have smoke!

If it's the air injection pipe emitting smoke then the fix will be simple: replace the check valve. It's the (sort of) bell-shaped device next to the cam cover; to the right in your photo. These are readily available.

Almost certainly not related to your running problem, though.

The air injection system is fairly benign. It simply injects fresh air into the exhaust ports. That's it. This in itself is not detrimental to engine performance... although the belt-driven air injection pump does draw a couple horsepower.

A failed checked valve, however, should be replaced as the exhaust gas travelling the wrong way (into the air injection pump) isn't a good thing.

Cheers
DD

 

Great call out. I was chuckling to myself, as I purchased an electric ignition & had the jaaaggg towed to the specialist today.
Super great guys, that informed me I already have the electric set-up :-)
Ill update the thread once the chaps conclude their diagnostics.

 

Fantastic Doug, thank you very much for the info. I'm passing it on to the shop I took it to.
I'm in the Portland area, I'm hoping this 2nd shop is significantly more knowledgeable than the 1st :-)

 

Thanks Guys. I finally found a credible local shop. Unfortunately looks like I need an engine rebuild :-( Super surprised as the previous shop said the engine compression test was excellent, then took me for over $4k to rebuild my rear differential (which i only did on the basis of a strong engine.). Insult to injury, the new shop were very surprised why the back end would need rebuilding, given the awesome condition of the Jag. Now I need to figure out to sell it as a mechanic project or LS swap it..... Rough classic owner day for sure :-)

 

What rotten luck, however there must be heaps of good used XK engines out there that you could swap over.

 

I'm seeking a replacement engine. I'm surprised the engine gave out so quickly.

 

Any idea of the engine's milage?

They usually only fail if neglected (or abused).

 

@redtriangle that is why I'm so perplexed by this. I've owned the car for a few years & spent continually to keep it reliable as a daily driver. Having recently put over >$6k in work, as I was reassured by the shop that the engine was in tip top shape. It has around 140,000 miles. I'm finding it challenging to find knowledgeable folks in the region, & not being very mechanically minded, I'm rather unsure what is what now. Whilst I'm hesitant to do so, I might have to bite the bullet & sell it as a project car.