Hi guys!!! I've been reading this forum for a while now and I'd like to join your community.

I have a xj6s3 loooong story...
I was young and wanted a v8 but wanted a nice looking car too, rebuilt a 253 hold3n v8 in my twenties and saved it till I found a suitable car....xj6....beautiful.
picked it up, started engaging engineers, soo. Found out its pointless doing heavy modification of any vehicle in Victoria, cost + red tape.

so now I'm restoring her. Which I'm kind of happy about now thinking about it all.

anywaysssss I have add and get a bit off track sorry.

car surging and stalls sometimes while driving.

what I have have planned to check on weekend :

leaks in intake

stuck egr.

fuel filters.

Fuel tank condition (boroscope)

fuel tank swap over switch.

distributor.

vac pressure/fuel pressure.

now what else might be good to look at whilst in making a day of it.

check if tappet hold down kit has been installed.

its unregistered and I would love to get her roadworthy.

electrical is a mess, bit luckily I find wiring therapeutic haha sick I know.

also any good info on the quasi efi system and how it gets timing, injector duration and volume.

should I keep it stock or smash a cam sensor and run aftermarket ecu (speeduino)

any advice would be fantastic I've trawled this forum ( hence the check list) but I'm a bit scattered and have a hard time focusing. ( my problem not yours) but yer....I'm very good at breaking g things and I really don't want to break my mid life crisis car.

 

surging idle is usually a vacuum leak.

check the air filter canister hoses from the front "trumpet" all the way to the 90 degree aluminum elbow for cracked hoses.

 

I think you have a very good list. Personally I'd begin with checking for rusty fuel. These cars have a long history of fuel tanks rusting.

Remove the fuel filter and empty the contents into a clean, clear container. What you see (or don't see) will dictate your next steps. It only takes a minutes to do this.

That said, a bit more detail on the surging and stalling would be helpful. Does it happen only only certain conditions? Does the engine restart easily? Does engine temperature make a difference?





I wouldn't call it a quasi FI system. It's an actual FI system. But of decades old design!

The Air Flow Meter (AFM) is the primary player in fueling. It tells the ECU the amount of incoming air and the ECU adjusts injector pulse width accordingly.
A pressure regulator control fuel pressure to the injectors by regulating how much fuel is returned to the tanks
The ECU richens the mixture for cold running via a coolant temp sensor.
For cold starting a stand-alone cold start injector is used.

Go here for the full details
https://www.jagweb.com/aj6eng/42efi/index.php


Your car, your choice!
The existing Bosch system work pretty darn well even though it's an elderly design. Quite often faults are easy and inexpensive to repair so there's no reason to assume the easiest/best solution is a full system replacement.

You say you are restoring the car so I presume it needs a fair bit of work in all areas. I wouldn't be too anxious to dump the existing fuel injection system at this point. Put your effort in the getting the car done and then start contemplating your fuel injection upgrades.

Just my two cents
Cheers
DD

 

Awesome I did a quick seized but I'll go over everything and v
Clean out throttle body just in case, I always miss the easiest stuff so that's really helpful!

 

Most valuable 2 cents I've ever received.

I've turned a corner woth this car, the fi system is elegant and Ingenius to be honest.

I can't say much about the surging/stalling but I doubt it'd be a bigg issue. I've only driver back to a garage, and did not check thoroughly yet.

I'm sure I'll find the problem with all the advice given.

I am quite curious as to why the colt meter has capacity to show 18v though.

Do any of its electrical systems require more than 12v? Aside from the dizzy.