1987 Jaguar XJ6 Base v6 4.2

This will be a long story but I'll try to partition it out as much as I can... I'm NOT A CAR MECHANIC but I do know how to turn a wrench (it just so happens to be on fixed-wing aircraft, not cars).

The Start
I bought a Jag in Tucson, AZ that hasn't been running in 5-7 years (or so the owner said). He 'performed' all the basic tune ups - oil ,transmission, power steering, new spark plugs & wires, etc etc. The car was originally purchased in California.


Some Middle Stuff
I double-checked all "tune ups" and corrected the spark plug gaping, installed 6 new OEM equivalent fuel injectors, fuel pump, dropped, flushed, and reinstalled both tanks, flushed the fuel lines from tank to fuel rail, replaced both fuel level senors & floats, new air filter, new fuel filter, new oil filter and oil, dropped, cleaned, and reinstalled the first Catalytic Converter (nearest to the engine), replaced the battery, and some other random crap.


The Now
Sometimes the car starts, moves around a bit, acts "normal". 90% of the time it hates life. From a cold start it will fight to idle and I have to give it some gas. About 2-3 minutes of that it will idle fine (around 400-600 RPM) but once it hit 60-ish C (on it's dial, anyways) it will: A) Shut off (gurgle gurgle - stop. Like it isn't getting enough fuel) B) Just suddenly stop or C) Choke a bit, then slowly lose RPM. If I try to gas it the car just stops sooner - the RPM plummets.
When I do manage to drive it a bit it REFUSES to shift to 3rd gear (I dropped the transmission pan and there wasn't any chips or other signs of metal and the fluid looked great. So I topped it back off.).
My next project it to completely remove the exhaust system, soak, clean, and reinstall it.

Side note: The drive side fuel cross-feed valve (or w/e we can call it here) is in-operable - looking to replace that. So if there's to much fuel on-board it all dumps (and overflows) to the right tank. I just keep about 3/4 of the right rank full and make sure the switch in the cab is on "R".

Any ideas? Thanks in advanced.

 

Random thoughts....

Even though you've cleaned everything I would pull the fuel filter again and empty the contents into a clean jar. You might still have some rusty fuel.

A fuel pressure test might be helpful.

Any black smoke from the tailpipes?

Hvae you checked the coolant temp sensor? An easy idea to to pull the connector and jump the terminals wil a paper clip or wire. This tricks the ECU into think the engine is warm. Any change in running? (Naturally it won't run well when stone cold with the temp sensor bypassed so wait for it to warm up)

Is the ducting between the Air Flow Meter and the throttle body tight and leak free?

Are the fuel injection ground wires at the end of the water rail clean and tight?

Cheers
DD

 

Just nit picking. It is an I6, not a V6!

Welcome to the fun.

Some duplications. But, start at the rear and get the fueling in order. Remove the large pugs behind the ruberoid plugs in the valences behind the rear wheel. have new gaskets on hand. And big container, if there is a lot of gas in them. Check the socks on the ends of the pickup tubes. Remove or replace.

New hoses in the boot and filters before the pump that can be inexpensive and easliy changed. This is gravity, so high pressure filters not needed. Safety and fuction is the key here.

If the big jaguar filter is full of crud, it will cause a lot of heaches. Repalcing a dirty one is the only workable option.

You might be able to clean the selector valve and return it to service.

David Boger posts here and is a great guy and source for good used parts as wellas NOS stuff at reasonable prices. You might go there for a filter and valve.

The fuel regulator uses vacum. So, use a pump or whatever to see if it's diaphram is intact.

A fule pressure guage is needed. Measure raw pump pressure pre regulator. Up to PSI should be ther a tad less will work. Measure after the regulator. Around 36 PSI to get good injector response.

As to the injectors, I'd just get SD Faircloth to service them. Sitting idle can not have been good for them.

Once having done this plus Doug's ideas, the fuel system should be in order.

If it still messes up, move to ignition. Hopefully not needed, but if it is come back and i or other real Jag geniuses will help. I am not the latter!!

Carl

 

Ha-ha, yes, my bad. I6.

I'm not quite sure what the "Big Jaguar Filter" is, the fuel filter?

I did attempt to clean the selector valve, it moves very slightly now. I'll try again not that it's been running more often since I've done that.

"As to the injectors, I'd just get SD Faircloth to service them. Sitting idle can not have been good for them."
I've already replaced all 6 of them.

Q&A
Any black smoke from the tailpipes?
No

Have you checked the coolant temp sensor?
Nope

Is the ducting between the Air Flow Meter and the throttle body tight and leak free?
Yes, but I will diffidently re-verify at this point.

Are the fuel injection ground wires at the end of the water rail clean and tight?
I did a check of every wire I could reach under the hood. Besides some bad conduit, everything is snug and nothing's broken (that I've found).

TO DO
- Recheck all the fuel lines & filter.
- Drain fuel from tanks, add new, clean fuel.
- Extra procaution: Removing tanks and cleaning again.
- Add in-line fuel filters before the fuel pump & selector vavles.

- Check coolant temp sensor.
- Recheck duct at Air Flow Meter & Throttle Body.

- Check the Fuel Regulator.
- Check the fuel pressure w/ gauge.



Thanks for the replies and help. I've got a lot to get do today.

 

Have a read: -

Fuel injection and the Jaguar XJ6 4.2 Series 3 / AJ6 Engineering