G’day Grant, sorry to disturb you, but I’m not having much succes on getting my '88 XJ-S HE to run smoothly, and I seek any advice you maybe able to offer. I’m assuming you can see the rest of this thread and that I have followed your tips and advice re setting up the engine for tuning, as well as the very welcome advice offered from other members.
A bit of history, the car had a leaking rear main bearing seal, and I had the lads in Darwin (Darwin Radiator repairs and auto) have a go at replacing it. One of their less skilled techs rotated the engine whilst the crankshaft and cams weren’t connected to each other (having dropped the crank down to access the seal - yep)! Recognising that this was probably very bad, I got them to get the cams and crank realigned using the Jag cam shaft jig, replaced the waterpump, camshaft chain (rooted), and tensioner. Cams were in good nick.
After much effort trying to get the car to run smoothly, I was posted to Newcastle, car still very unreliable - started well, and ran but was susceptible to stalling at idle. At this stage I took the car off the road to overhaul the rear cage, and when completed restarted into the tuning issue again. Initially the car started and ran ok, with a slight miss at highway speeds, gradually getting a worse stumble until it ran very roughly, and stalled at idle: roughly half an hour from cold. So I put the car on a dyno here in Raymond Terrace: Car running lean, power at 150 HP.
Had all the injectors off, cleaned and flow tested at the dyno place, new filters, new pintles, replaced all underbonnet fuel line, ferrules, and fuel clamps.
I addressed the lean problem by checking fuel pressure (39psi, new fuel filter, sump tank clean (it was clean), blow through fuel lines (clear), Fuel regulator RHS = OK, LHS rooted, I thought beauty solved it! sadly no difference, other than now I appear to be running too rich.
So now I picked up on your various posts on how to make your XJ-S reliable - jump in it and drive to Adelaide reliable etc. Accordingly, I have done the following:
a. Throttle discs/bodies cleaned;
b. Throttle discs set to 0.002" gap. Made sure rods weren’t impeding closure;
c. TPS set to 0.32 - 0.36v mine is at 0.325v (my original TPS was rooted now replaced);
d. Plugs initially set and gapped correctly (probably a bit sooty now);
e. New fuel regulator (LHS) replaced (original one rooted);
f. Timing initially set to circa 10 BTDC at idle;
g. Followed your “HE Tune up Grant’s Way” which sadly didn’t improve things:
(i) idle can be improved by rotation of dissy although still rough/missing badly;
(ii) performance can be improved by rotating dissy but still stalls at idle.
h. I checked that when rotor at 1A the harmonic balancer timing mark was at 10 BTDC;
i. CTS renewed although it was good;
j. ATS checked ok, although as you noted it doesn’t do a great deal;
k. re checked the AAV, working, I had earlier got a new bulb assy from Jonas in Latvia/Finland…;
l. Set the timing at 3000rpm at 18 BTDC (against your direction but just to see how far I was out - not much);
m. Vacuum advance works;
n. Inlet vacuum is 15 Hg/" measured on RHS inlet manifold;
o. I have now removed the cold idle setup on the RHS leaving the dump valve, connected to the Vacuum advance as per Caspar Graham (You tube - Aussie Daimler V12) in the vain hope that a component of that system was rooted and affecting performance.sadly no improvement;
p. I checked the amplifier unit, mine isn’t in very good condition, although working? Wires inside are brittle, Zenner checked (it is acting like a diode but that’s as far as I can check). Cap measures ok at 1uF. Tacho works…I have ordered a new amplifier unit from SNG at vast expense;
q. Adjusted the ECU knob left and right which didn’t seem to do much, so I returned it to the mid-point. ECU Vacuum feed is good, hiss when disconnected, and definte vacuum detected.

So that’s where I am at. Any advice gratefully recieved, because I’m running out of good ideas.
Cheers Chris

 

Bugga.

Lots of thoughts and I will sort them in time and respond.

Initial thoughts:
EFI loom, highly suspect due to age etc.
Resistor Pack, RH inner guard, plug and socket is grubby.
Cam Timing is off. Not the easiest to set up anyway.
Plug leads, how old?
Primary coil resistance COLD, should be 1.2ish, then heat it up, Mum's hair dryer, and read it again, should be near the same. They be OLD now and live in death valley. Then check the front Aux coil, same procedure, but at least that sucker is in the cold air.
Check the spark quality when it chucks a hissy. Get your "mate" to hold a lead whole you crank it, and how far he jumps gives the clue. JUST KIDDING PEOPLE. You need a FAT BLUE CRACKER at ALL times on this thing.
With the Amp and FOR issues, and driving it, the Sparkers are dud. The HE will not burn clean plugs once they are sooted.

Beer O;Clock (AKA I need my beauty sleep), be back later.

 

As discussed Chris.

You may have this valve, you may not ??

 

Good evening and many thanks Grant,
I recieved my new Amplifier in the mail today: didn't make any difference. The car now tries to start but doesn't catch (as before)? I'm starting to suspect that injector harness as you mentioned..
Checked the spark using a pulled plug, and it was nice and blue.
Anyway, I have started to remove the plugs please see enclosed pictures: broke 6A insulator, and I will take the compressor out tomorrow to get at 1A, and 1B. They look pretty sooty to me.





Micro switch on pedestal

I don't have a Blue/White valve on this car, as suspected. However, I have enclosed picture of the micro switch on the throttle pedestal.
I'll ditch the inline unit for the vacuum feed to the ECU as we discussed.

 

Thanks Grant, an interesting article nevertheless.
OBTW I cleaned that plug from the injector harness using contact cleaner, came out pretty easily, and wasn't covered in gunk, so probably OK.
I also checked the ECU vacuum hose for oil/gunk. It was very clean, and I tried the hose integrity to the ECU, and it held vacuum?
Do you have a failsafe test for the injector harness, which I understand is basically four wires?
Anyway, things are getting interesting!
Cheers, Chris

 

Ok Latest SITREP.
After consultation with Grant, we are plumbing for the Fuel Injector harness as the most likely culprit. As I was most of the way through changing the plugs, which is best done by removing all the 'stuff' in the valley anyway, very little further effort is required to lift the A/C compressor and get at the EFI harness and inspect for broken/short/open cct wiring, and maybe even make a new harness. Sounds excessive but the harness has been in the valley for 36 years, and in Australia where ambient air temperature does nothing to assist cooling when the car is stationary.

In addition and again in consultation with Grant:
a. I have removed the Cold start vacuum system on the RHS of the car;
b. I am removing the PCV hose into the LHS air cleaner and leaving that PCV system to free atmosphere via a tube behind the drive belts. I was actually thinking of one of those old Chevy/GM PCV breathers that used to sit on the top of the LHS rocker cover, simple and effective?
c. I am removing the RHS Fuel regulator and inserting a fuel pressure gauge adaptor fitting;
d. The plugs I was using were NGK BR7EFS, Grant advises NGK BP6EF, which I can't get but, NGK BP6EFS are available, and close enough for government work.

A further test of the Vacuum feed to the ECU will be conducted whilst I have acces to the rear cross pipe (throttle pedestal removed).
I will try and make an adjustment tool for the ECU fuel adjuster.

More news once I have the harness out and inspected.

 

20 April SITREP,
Removed EFI Harness, as well as the distributor because a previous fixer had put one of the P brackets under the distributor. Harness is very brittle, and has an obvious break of insulation at 1B injector. I'm sure that these two wires pictured were shorteing to each other. This would either: prevent injector operation; or make the injector stay on; unsure which way the solenoid works. I initially thought if the injector stays on that would explain the rich mixture, I'll have to go back to Grant's information on injector goupings. Also if the ECU is getting a constant injector on signal that could also impede normal fuel injector operation?
Notwithstanding, the harness is in very poor condition, and needs replacing. Due to a paucity of replacement items, this looks like a handbuilt job, using much more heat resistant wiring. A visit to Jaycar is in order. Having said that it actually doesn't look to difficult....


Harness on the brew table in the workshop

 

FYI
If the harness shorts to earth the injectors stay open.
Best thing to do is to buy some EV1 plugs and use some silicone covered wire to build a new one.
I suggest unwrapping the old outer carefully, laying out the old one on a wooden board with pins/nails to hold it in place, and then replace it wire by wire. You will have to splice each wire onto the wires coming out of the original plugs, but usually the last few inches are not cooked, so it should not be a problem.
Not a huge amount of work, more just carefull detailed stuff, and problem solved permanently. When reinstalling it, cable tie it ro the fuel rail, not to the bottom of the V.

 

well found Chris and as expected.

Nor difficult at all to make your own, and more satisfying in my opinion.

Like the rest of the car, "simple as they come", except in your case that ABS system, oh dear.
I reckon with your "pull" at the Base, you could requisition a NO ABS Donor Car be Found, maybe not, but ?????

 

Good morning Greg,
EV1 plugs I assume are the actual connectors to the injector? The ones I have were replaced in Darwin but; they came off the injector far too easily, so I suspect their electrical integrity. In talking with Grant we established that we have four sets of three injectors firing in groups of four at a time? The point of this thread is to maintain some sort of electical coherence, and as such how many colours should I go for. Grant suggested that he completed the task with two sets of trailer wire consisting of two lots of seven wires.
I'll just go down to the workshop and unwrap the rest of the harness and see what each pin of the plug connects to. There are several terminated pairs within the harness, unsure why. I also should have a wiring diagram in the manual, trouble is finding the right derivative of the several models described in the book.
I can get high temp silicone wire from Jaycar (Aussie electronic retailer) in 30 AWG in 5 base colours (one being black). Which maybe sufficient. Anyway many thanks for your advice, more to follow.
Cheers Chris

 

21 April SITREP -
Removed remainder of insulation tape and found at least four more breaks/shorts in the harness: it is stuffed. Not only broken wires but soaked in filthy oil which is conductive. I am truly surprised the injectors worked at all.
I have ordered 16 gauge, high temp silicone wire in block colours to match the white, blue, green, grey, and black wires in the exisiting system (yep they are pink and black and orange and whatever, but you get the idea);
I have also ordered an automotive 8 pin plug to replace the engine bay connector ;
Where does one find the actual injector connectors? Looking hard on the web but no results so far.
Pictures of harness just to demonstrate how bad a 36 year old harness is under all that insulation tape..my recommendation don't tape your wiring; all it does is hide breakages and brittle wiring.

 

The connectors are the Bosch EV1 style. Not sure about Australia, but in the states they are readily available from Amazon and automotive suppliers. You can get them wired with pigtails. When I redid my harness I bought the connectors and the pins from Digikey, an electronics supplier. That way I had one fewer connection in the wiring.

Just had a quick look at Australian ebay, and this is the sort of thing you want. Although you'll need 12 not 8 obviously. https://www.ebay.com.au/itm/18367055...Bk9SR_CJmYTgYw

 

Thanks Chris.

Those snaps confirm what we have been saying for years about this loom.
So many owners refuse to accept that this loom is NOW the weakest point of the system.

Hopefully they see this and open their eyes and minds.

 

Good morning Gareth, many thanks for your time and trouble to forward that link. I have ordered two sets just now, seems a very reasonably priced solution.
Kind regards,
Chris

 

SITREP 22 April,
WIre ordered from Amazon 16 gauge, silicon insulated, 8 colours x 13 Feet;
EV1 connectors x 16 (two sets of 8) ordered on e-bay, courtesy of Gareth;
Car loom connector ordered from Jaycar (Deutsch connector 4 pin x 2)

Probably arriving 25th April (ANZAC Day). Looking forward to showing the resullts of my endeavours.
Cheers Chris

 

Good evening All,
Quick update 7th May:
Work has slowed due to social and automotive commitment: the all British Day in Newcastle. Displayed my Series 1 Daimler VDP Double Six, which is always a favourite.






Despite Gareth's excellent advice unfortunately the EV1 Fuel Injector connectors don't fit, so I have used the ones I replaced in Darwin connecting onto the pigtails, mainly because I don't have a pin extraction tool. I gave it a shot with a jeweller's screwdriver, but not playing. Notwithstanding, another interesting hack is that a small spade connector works fine in lieu of the only original connector I had left on injector 6B, this hack courtesy of Mr. Ian Hissey a very technically astute member of the Jaguar Driver's Club - Hunter Region. The old connectors are very hard to come by, and the best I could do on e-Bay was about $Aus75.00 each! I imagine they may be more readily available in the USA where most of the XJ-S' ended up.
So the wires from the connectors to the inline connectors are finished, just making the wires from the inline connectors to the car harness. Interesting observation is that I cannot find a firewall plug for the injector harness travelling back on the RHS to the brake system. My harness goes through a grommet into the passenger cabin (somewhere), so I am interested in finding where this goes. I'm positive it doesn't run all the way aft to the ECU..well almost positive.
Anyway, on, on! hopefully this is the issue, and enjoyable driving ensues.
Cheers, Chris