WOW! All you guys are amazing, I just hope that all I'm learning can help someone else in the future, though, I did post a thread with pictures on boot opening problems that was well received. What a fabulous site this is!

Jhartz, RJ237, and Mark, many thanks for your replies:

To Jhartz, your comments seem to reflect the problem(s) I'm having, in the sense that there is reference to a Mass Airflow problem listed under the Security DTC test. I think I'm beginning to understand the 'Bore Wash' comments, in basic terms does this mean the fuel being injected on cranking has washed the oil down past the pistons, or something similar? As far as the Temperature Sensor is concerned (again until I gain experience) where will I find it (remembering my vehicle is RHD), and is there a way to test it? Guessing that the Temperature Sensor is like a 'choke' this could also make sense, as it seems to be trying to fire on cranking!

To RJ237: Thanks for the heads up on the 'check eng' light, I suspected it stays on until the engine starts (this proves 2 issues, 1. I've never had this non starting problem before, and 2. I should take more notice of what's going on with the instrument panel directly in front of me!). I also thought the low voltage may result in spurious DTC results, hence the trickle charge the battery's on. I purchased an Automatic Charger today, one that cuts itself off when it senses the battery is charged so I can leave it overnight on charge. The 'stepper motor' noise on the Throttle Body, anything to worry about? I had intended removing the Throttle Body to clean it, should I leave this for the moment, or is it worth doing?

To Mark: Sensible suggestion, somewhere in this thread someone said about the battery being around 13.2 to 13.8 volts, and apart from the Mass Airflow reference it seems there's nothing listed in the DTC's that are relevant to a non starting problem.

So, it appears the next attack is cleaning and checking the Mass Airflow Meter, checking and cleaning the plug, and making sure it's well seated. Then, reconnect a fully charged battery, put a few squirts of engine oil in all 4 cylinders of one bank, throttle wide open, and try starting?

For those who asked, the car has done 121k, a Hard Reset had never been done by me until 2 weeks ago, and the battery is just over 7 months old (100ah).

As you can all see, I'm trying nearly all your ideas. I feel assured that with all this knowledge I will get there, please keep ideas coming.....

 

good evening - I'm new to posting on jaguarforums, so struggling where to post - I have a similar problem, I drive my Jag for the winter so just pulled it out today, started up no problem and I drove it for a short distance, parked it and no when I tried to start it again, it will turn over quickly but not fire. tried two different keys and same result. any suggestions?

 

Yes, clean the MAF sensor first, and check the connector as mentioned.
This is probably not the cause but will rule it out as well.
Not much work, and needed to do from time to time anyway.
Do it with the battery disconnected, and do a hard reset after finishing.

There are some values available for the MAF sensor reading, but that requires a running engine, so forget that for now.

Before you take the plugs out, and with a full battery, try the suggestion from JHartz first; it might save you work.
If you push the pedal all the way down before starting (like a kickdown), it will cut off the fuel supply.
If you then engage the starter for periods of 20 seconds several times, you might be lucky, and the oil from the crankcase might be thrown up to the cylinder bores, restoring compression.
Try start the engine normally after 3 or so times.
Several forum members succeeded with this method.

PS. I should take this one by one, and not mixing up by removing the throttle body right now, as it is most likely not the cause.

Borewash most likely, follow the suggestions and try.
Some details on your car might help.

 

Ok ericjansen, I will try this out tomorrow evening when I get home. I hope our new friend stephenlutz finds the suggestions help him too?

 

You do not need to remove the throttle body to clean it. A stick, a rag, and some solvent will take care of it. But don't spray throttle body cleaner into it, spray it on the rag. Make sure you get the gunk off the butterfly.

 

As Eric said, probably bore wash. Use the forum search to read up. In the future, just open a new thread rather than using an existing one. That is unless you are unable to start a thread because of a minimum number of posts required.

And welcome to the forums. You may want to follow the XK8 forum also, since the drive train and a lot of suspension components are the same.

 

+1 bore wash

 

Your understanding of bore wash is correct. That is why holding the accelerator to the floor might work: it cuts off fuel flow (same we did years ago with carburetors to clear a flooded engine), while the oil pump sends oil into the cylinders and restores compression (compression, fuel/air mixture, ignition).

Temp sensor is on the cross over pipe above the water pump (shiny brass thingy screwed into the plastic pipe with wires sticking out of it) and sends signal down to MAF.

Once upon a time I had same issue, it was a bad key (key had lost its program), but it started with the other key (needed to reprogram both keys, later on). Might be your problem (but not Lutz').

All else fails: a tow to your dealer or really good indy (last time over there, seems I saw one in every little town off an A route). Cheaper than a heart attack caused by stress and high blood pressure for which this brand is known.

 

Ok all. I got the battery charged to 13.7V, put it on the car to try the 'bore wash' solution suggested by a few people. As advised I put the accelerator hard to the floor and cranked the engine. After about 5 seconds there was one almighty bang from under the bonnet, frightened the life out of me, especially the smell of burning fuel!

I switched off and tried again without my foot down on the accelerator, it was trying to fire here and there but mostly nothing. Then, it blew off the small breather pipe that fits to the left-hand cam cover (at the front), leaving a very small deposit of engine oil on the cam cover where the pipe fits. I'm beginning to suspect a blown head gasket, or am I just stabbing in the dark here, I also noticed the water colour in the expansion tank was very rusty coloured?

Mechanically I'm pretty clued up, it's the electronics that fail me every time. I changed both Primary, and secondary timing chains, tensioners, and guides about 6 months ago, the car fired up first time and has run great for months since.

At the same time I changed the Thermostat Tower for a metal one, replaced the Thermostat itself with a new one, and new water pump. But, as said, everything has been running fine for months (about 1.5k miles).

I guess a compression test might tell me something, not sure, or maybe cranking over with the expansion tank cap off and see of there's any pumping out of the water, there doesn't seem to be any water droplets on the oil dipstick.

The huge bang from under the hood was strange, I understood that the fuel was cut off when putting your foot hard to the floor, so what exploded? Any thoughts would be appreciated.

Another thing bothering me now is the amount of forum posts being limited on here, if so, should I start a new thread, cos I will be goosed without you guys out there?

as always, I'm open to suggestions and ideas, getting really worried now!

 

The bang would likely be that you cleared enough fuel to get to the sweet spot
to ignite the remaining fuel.

Trying again with the foot down would probably have led to success.

Foot down, crank engine. If it wants to fire keep cranking. If it will not fire
then perhaps all fuel has cleared, in that event keep cranking and slowly
release the gas pedal partially until it at least stumbles. At that point
it is likely to fire on the next crank.

It takes some experimentation.

If the engine is not building compression, then you will be needing to
do the oil down the sparkplug hole routine for borewash.

 

When you did tensioners and chains - did you torque everything back to specs? 'Big bang' under bonnet sounds like valves timing is off. Like if sprocket 'slipped' out of timing. Bang should be out of exhaust pipes .

If this happened to me I would be checking the very basics: do I have compression at TDC (finger on plug hole test) and do I have a spark close to TDC.


P.S. I just had few drinks though... take this advice with caution :-)

 

I'm going with Bore Wash..... Had it fixed it.

 

I think I am siding with above, and blame it on fuel ignition.
That can give big bangs for sure, especially if some collects in the exhaust manifold or exhaust.

I am not sure if your ignition was or off when you pushed the accelerator all the way down, but I guess you might have had injectors spaying fuel before the cut off (not sure on this though).

If you want it the quick way, try it an other time, and prey a hail marry before.

If you want it the safe way, then it is time to remove the spark plugs, check the compression while you are there (measure wet with some oil in the bores), and attempt the start if all plays well.

I hope the breather did not break, you should be able to push it back in.

 

Hi ericjansen. Yes, I think you and 'plums' are right, try again, though remembering the bang I'm leaning towards some oil down the bores, wouldn't hurt to check the plugs as well!

The breather didn't break no, it went straight back on and clicked into place.

I'm not convinced the valve timing is off, it only banged when I put my foot down on the throttle, it's never banged before, or after, without my foot down.

After this weekend, I'm also going to change the Temp Sensor, no harm there, and while I'm checking compression I will check the timing as best as possible without the proper tools for locking cams etc..

Onwards and upwards....

 

Very interesting thread,sorry I can't offer any help I know how frustrating engine problems can be when you can't find the cause.
Keep us posted on how you get on and good luck,
Take care
Andy

 

Still working on this problem and had so much help from all, particularly ericjansen, who is an absolute trooper.

However, after doing some work on the car yesterday (in the freezing cold I might add) I learned something just this morning that took me all my time to zip my mouth shut.

I previously stated I took the car into town, then parked it, next day it wouldn't start, GUESS WHAT! My wife decided to tell me that she saw some oil/water/fluid whatever underneath the car, so she started it, backed it up a meter or so, moved it back to where it was and switched off, total running time of about 30 seconds!!!!!!!!!!!!!

OUCH! Seems the 'bore wash' suggestions could well be the problem, she said the car did sound like the 'choke' was on, Q: how do you keep your temper in these situations, after making her breakfast I haven't spoken to her since! (maybe the answers to my question defy the Forum's protocol on swearing so should be carefully submitted?).

So now it's put some oil down the bores, as I already have the cam covers off and plugs out. I've ordered some new cam cover gaskets, and after checking the compression, checking the valve timing, and general checks, I will get it all back together and attempt starting.

Unless someone has some clear instructions otherwise, I don't intend putting my foot hard down then starting, the crankcase explosion last time nearly gave me a heart attack, I'm hoping the oil down the bores will suffuce.

Couple of other things from suggestions so far. I've fitted a new Temperature Sensor, and a new Full Load Breather pipe, I also have an old MAF I know was working earlier. New plugs too I just got this morning, regapped and ready to fit. Phew!! that's it for now, on with the saga, and will keep you informed.

Special public thanks to ericjansen again, also Jhartz, King Charles for their continued support during this thread :-)

 

So what now ... trying to explain to her that a Jaguar can not be moved for a meter ... after she tried to help you exploring the stuff under the car .... buy her a bunch of flowers, will do more wonders than the swearing and making up afterwards ..... .

Seriously, it was my pleasure addressing some of your questions by PM, although I think, and mentioned several times to you, there are far more experienced members here on the forum.
My car is simply not breaking down enough .... oeffff .... playing fire, I know ...

We will wait the simple turn of the key and its good results in the coming week, good luck!

 

So, where are we?

 

Hi Jim. Well, I didn't get the wife any flowers, but I did manage not to say too much!

Got myself a new compression tester today, also the new genuine oil filter arrived, and a new sump plug. I've also taken the advice of quite a few people on here and got some Engine Restore, produced by Ametech, I hope this is the right stuff. Again, trying to follow the plethora of advice regarding which oil to use, I finally went for 10W-40 Semi-Synthetic, it seemed the middle order of what people suggested for the climate over here, and what the store told me was right for the car.

The cam covers are still off though I have cleaned them out thoroughly, cleaned the place where the Full Load Breather, and the Low Load Breather are fitted on the other cam cover. The new cam cover gaskets have arrived, and I have the new Full Load Breather pipe.

Next job: put some oil down the bores, remove the fuel pump fuse/relay, and crank it over without the plugs in to try and get some oil round the bores etc. Then put it back together minus the coil covers, put a little more oil down the bores on one bank, plugs in, and see what happens when I turn the key. I've got the battery well charged up, so...

I don't know how to thank you guys enough, I just hope I've got everything in my head that needs doing, and in the right order?

Once I get it going (he said!) I'll get the oil warm, maybe take it for a run, then change the oil and filter, and add the Engine Restore. Is there ANYTHING you masters out there can suggest I do in addition to what I've written? BTW: I've checked the valve timing, made sure piston was at the top as close as I could without an engine lock pin, and all four cams were in-line, I also checked the cam bolts were tight.

I will have some experience to write to you guys, have taken pics too, WHEN I get it running, I will share everything with you all. Paul.

 

Sounds like a plan.