Thanks Mark, I will

 

The TPS is the "Throttle Position Sensor." It is located under the throttle push rods turnstile. There is a 3-pin connector coming from the TPS. Here is how you test and adjust it;


THROTTLE POTENTIOMETER SENSOR (TPS) - ADJUSTMENT

The throttle pulley assembly must be unbolted from its tower to adjust the pot. Disconnect the rods to the butterflies.

Have the ignition on and the throttle pot assembly rotated to the idle stop. The engine may be running or not.

Connect a digital voltmeter to the RED and YELLOW leads from the pot without disconnecting the pot from the harness.

Adjust the pot by loosening the three small mounting screws and rotating the pot until the voltage reading is within 0.32- 0.36V.

Tighten the mounting screws and reassemble. Make sure the reading remains within limits when the linkage is all together and the engine is running at idle.

 

Thanks Safari,
Today I will adjust the Throttle Potentiometer Sensor (now I know it is the TPS Thanks)
and try the starting fluid, will let you know what happened...

 

OK,

TPS = Throttle Position Sensor, or Potentiometr to some.

It has a 3 wire plug where it attaches to the chassis loom.

I would simply spray some of that starter fluid "up the spout" of the air cleaner as it is fitted to the engine, and by that I mean the funnnel looking item that points at the radiator. I do NOT recommend starting, or even trying to start a V12 without the aircleaners attached. PARTICULARLY one that is having starting issues anyway. They have a terrible habit of backfiring, and BELCHING flames out of the throttle bodies. Great fun, but crap for your paintwork, and usually has you doing things in your clothing you really dont want to air on here.

The HE engine WILL NOT start with crappy spark plugs, NO EXCEPTIONS.

I run NGK BP6EF, NO resistor, and NO flat nose plugs. I gap them to 0.025", and apply anti-seize to the threads.

Remove the distributor cap BEFORE doing #3 & 4 on the B bank, and #3 & 4 on the A bank. You run a very HIGH chance of cracking that cap if you leave it attached.

If your spark is not so good AT the plugs, replace the HT leads with GOOD quality leads. I run Magnecor ONLY on the V12's.

I have attached a couple of Word Doco's I wrote a long time ago. Some of the stuff is not related, most is.

Adjusting the HE TPS.doc

HE Tune up.doc

XJ-S ECU Pinout table.doc

 

Thanks Grant,
I will follow your advise and keep the air cleaners as fitted to the engine. Will change the spark plugs, it has Bosh HR6DP, but I will install NGK BP6EF as you recommend.
Yes I will remove the distributor cover, good point, I had not thought about that, even if it is obviously very tight in there. I will also look for a set HT leads. Will let you Know what happens...

 

Hello Grant,
I just want to thank you for the DOC files you sent me, I can really use all the information you put there. Again Thanks

 

I installed new spark plugs, but I am waiting for the new cables to arrive. Also installed a new liquid temperature sensor.

 

I installed the ignition cables, and re-assembled everything.
The engine started, very smooth. But lots of unburned gas, at first i thought it was because all the cranking, and I am sure it was; but after a while it kept doing it (unburned gas from the exhausts), every time I start the engine, it is ok at first, but after a minute or so, the unburned gas smoke starts again, the revs are very high too (2000 RPM) and it would not come down, so it may be the AAV.
I will do a tune up as per Grant Francis instructions. I want to thank every one for helping me start the engine, specially Grant Francis. I will inform what happens after the tune up and checking the AAV.

 

Unburnt fuel means the injectors are not closing properly, or the fuel pressure is off the clock. I suspect you have a short on the injector harness. Have you renewed it or checked it? If not, remove it now and check it. I think you will find it is cooked and therefore shorting the injectors which keeps them open and floods the motor.
Greg

 

I agree 100%.

Not sure if yours has "Cold start injectors" ????, if so, remove them electrically and fuel supply wise as they do jam open, and/or dribble.

 

No, mine does not have a cold start injector.
I have a question about the intake air temperature sender, as of now I have a resistor instead of the sensor, but I verifier the sensor and it works, but with a resistance value much larger than what is shown in the tables of the repair manual. The manual indicates a resistance of 300 OHM at +20 C, the sensor I have is about 2400 OHM at the same temperature. But I read in Sean's Jaguar XJ-S Tech Pages, that the resistance values for the air temperature sensor in the HE are just what I measured in my sensor. Is this correct?

 

No idea.

The ATS is a "trimmer" not a prime fuel sensor.

Many a HE running around with that unplugged, or broken wires with no ill effects.

The CTS (Coolant Temp Sensor) is the prime, and it does/can cause all sorts of grief, both the sensor and the wiring inside the plug and about 6" up the loom.

I have even had some where the ATS and the CTS are cross plugged, thats fun to sort out, as the looms and plugs are identical. Hence the pin out I supplied, I think??.

 

I have measured the resistance at corresponding pins at the conector of the ECU, so I know the ATS and CTS are not reversed in this car.
Your are wright, Grant, I disconnect the plug for the ATS while the engine is running, and nothing seems to happen.

 

Febres
Fix the over-fuelling problem, that is the most important thing to go after, both for your safety and the engine's health. It is the most dangerous fault you have. With that amount of over-fuelling, your oil is full of petrol (gasoline) already. I really thing you should pull that injector loom out and look at it. It is not a huge effort to do, it is clipped here and there to the bottom of the V, unclips from the injectors easily, and plugs into the loom on the RHS just behind the headlight nacelle.
Greg

 

The smoke problem is fixed. I replaced the CTS a while ago, but because the connector was completely rusted out, I cut it and was runing the engine with a resistor connected with aligator clips. While waiting for the connector and the air filters to arrive, I decided to connect the CTS with the aligator clips. That solved the smoke problem, the engine runs with no smoke comming out of the exhausts. I have not done a tuneup yet, as I wrote, I am waiting for new air filters. But now when the engine warms up it starts reving down to about 500 and up to 1500, it keeps doing that. It was between 500 and 2000 but I adjusted the idle thinking it could be cutting off and then reving up again, but it is not going up to 1800 (cut off revs) and I can not make it any lower, the screw is all the way in.
Any ideas od why it revs up and down?
Thanks.

 

The AAV is jammed.

AAV rebuild procedure.doc

There ya go, enjoy.

After that, and part of the "tune up", the TPS may be out of idle range, but that is explained in those other doco's.

If you are unsure ASK, and it will be sorted.

 

Ok, I will proceed with the tuneup and see what happens

 

I meant to write I will proceed with the test for the AAV and vacuum, If it is OK, then I will go to the tune up procedure

 

Hunting idle like you have is mostly a none closing AAV, combined with a TPS out of idle range, AND, throttle discs caked in Black Goo, and set incorrectly.

The fact you have the HOT idle screw ALL the way in, and its still hunting, is a dead give away.

Running these engines without air filters can be scary, so beware, they "spit fire", when annoyed. Does wonders for the paint work nearby, and your nerves.

Also, IF, you have the air filter backing plates OFF, the 4 holes are NOT blind, so a HUGE vac leak that the ECU will never compensate for, hunting idle, IF it even starts up, will be rampant.

 

The TPS is adjusted to 0.33, I will test the AAV and clean & calibrate the throttle disks.

Thanks