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Hi Sean
Electrician came today, believe it or not the car started as soon as he tried it but only ran for about 10 seconds. He did some tests on ignition to see if there was power at the coil harness plugs. also fuel pressure. He got the bank 1 & bank 2 failure codes on his OBD reader but there were no others present which I found strange, especially being it started and ran.
He suggested it may be the ECM because I,ve been getting a spark sometimes then it disappears and that was the module that controls the ignition procedure to the coils. He rang a couple of companies he uses for ECM testing but unfortunately they were unable to test Denso units. I have done a bit of searching on the internet today but have not been able to find anyone who can test it
In desperation I've looked on Ebay and there's plenty of my part number used ECMs, so I've taken a chance £140 and I should have it by Friday.
The one I have gone for the seller says came as a job lot of new jaguar parts, not in a box. It looks new in the picture and the chap has said he would refund me if its not working.
I'm hoping it will prove to be a new unit then hopefully I will be able to program it as a new module and won't get any coding issues i.e VIN, immobiliser etc.
Doesn't the ECM have to be recoded to the chassis VIN to work? Just talking out loud here, but I sort of remember that being the case.
Right. He would program the module as New in SDD and SDD will adopt the VIN to the ECM.
I believe best practice is also to start the process with SDD before removing the ECM and installing the other. If memory serves, SDD will tell you when to swap.
Having never replaced an ECM, Thanks Sean for the SDD advice. I was going to disconnect the battery first then remove the old unit, but was wondering how the VIN number could possibly transfer over if that unit is gone from the circuit. Your last post would make sense It just seems strange swapping modules over while the battery is still connected.
The ECM is arriving this morning. Unfortunately it's raining heavily all day, so i can't see me getting outside and my garage is full of stuff.
Having never replaced an ECM, Thanks Sean for the SDD advice. I was going to disconnect the battery first then remove the old unit, but was wondering how the VIN number could possibly transfer over if that unit is gone from the circuit. Your last post would make sense It just seems strange swapping modules over while the battery is still connected.
The ECM is arriving this morning. Unfortunately it's raining heavily all day, so i can't see me getting outside and my garage is full of stuff.
If I get a chance today will feedback later
Yeah I thought the same and take what I say with a grain of salt. I've never replaced an ECM. My comments are based on reading, not experience. See attached best practices guide
The ECM arrived lunchtime today and turned out to be a brand new unit sold as second hand less the original packaging. I managed to successfully programed it to the car using SDD 131.03 v.116
The configure new modules section is found in the Extras menu.
Unfortunately although the procedure worked and the new ECM is configured, this has not fixed the original starting problem, proving that my original ECM was okay.
The car did start after the programing was completed but again it only ran for around 10 seconds and now only fires once if your lucky and then dies immediately.
I have checked the DTCs now listed, see below
I have messaged the auto electrician and explained my findings,hopefully he will contact me tomorrow to arrange another visit.
I had a generator that would start and run for 30 seconds to a minute then shut down. It had a clog in the fuel line. The clog let enough fuel in the line to allow the generator to start and run for a while but it slowly starved it of fuel til it shut down. A few minutes later (after sufficient fuel had leaked by the clog to fill the system again) it would start up fine then die again a short time later.
As I was saying the relay is good, Prior to testing it I disconnected the battery first as I wanted to check part of the harness that runs through the pedestrian safety system turret for possible damage
Now I don't yet know if this is a coincidence but when I had finished checking the harness and re mounting the power distribution box I re connected the battery and attempted to start the engine. The engine fired immediately and was idling perfectly. I turned it off and restarted all okay. I then went for a test run which at first seemed fine but then the engine stalled but did start again. I decided to go back home as I was fearful that I wood breakdown again. I managed to get back although the engine cut out a couple of times but started straight away.
The fan was running quite fast when I got home and the engine seemed to be overheating. On checking the top hose it was highly pressurised and the radiator was cold at the bottom.
I decided to check the thermostat although I had renewed it when I fitted the engine a couple of weeks back.
The picture below is what I found when I removed the thermostat housing. I had used the original water rail outlet pipe from the old engine and had failed to see the piece missing in the middle.
This has caused the water to stop circulating hence the engine was overheating.
.
So I don't know if the engine starting problem is now cured because I disconnected the battery, causing a hard reset and the replacement ECM needed a hard reset after the programing I carried out yesterday Or was it me disturbing the wires under the turret.
Anyway I need to order a new water outlet before I can attempt another test drive.
Can anyone confirm that a hard reset is necessary for a new ECM to start working properly after programing?
If I could confirm this is the case then the ECM was likely to have been my problem and not a wiring fault.
Wow Stuart, and yikes, you're having your share of problems and then some. If SDD didn't tell you to perform a hard reset, I don't think it was necessary.
The car stalling and restarting is more indicative of a short than a faulty ECM and as you said, the ECM is new. Car shouldn't cut out. Once you get the cooling figured out, you might focus on the harness. If you can check all connections are clean and tight, and if you are able to safely wiggle the harness while in place, that might give you some indication.
Also check the harness where heat is highest near it. The cable can get brittle. Harness problems makes sense given the variety and ever changing DCT's as well.
That said, it would also help to get a new set of codes:-)
It would be great if a tech could weigh in as they've probably seen a bad harness or two. Hopefully one will chime in.
Fitted the water rail today, engine started okay so I decided to go for another test drive. Drove about 20 miles some in town then high speed motorway engine didn't miss a beat.
Then the dreaded engine management light and the engine stopped. It did start again but only ran for about half a mile then unfortunately It would only fire and run for 5 seconds.
Had to be towed back home and guess what the engine started as soon as I got it on the drive. While it was running I unscrewed the power distribution box and tried to wiggle it around hopping the engine would cut out and prove it was something to do with that area, but it didn't.
I had the engine idling for about 50 minutes and then went indoors.
Tomorrow is another day
I'm quietly confident that the problem is cured. I spoke with a friend who has his own independant Jaguar workshop unfortunately he is 250 miles away.
He suggested given the main symptoms which were loss of spark, to check the ground connection P1051. Sean had already suggested checking grounds from the off. But I was only concentrating on the ground points that were shown in the wiring diagram starting with GO.
My friend sent a picture of the location of P1051 as I couldn't find it. see below
When I replaced the engine this particular ground was not attached at this point, it had been damaged and extended previously to me owning the car and was attached as shown below.
I had noticed this ground and thought it was in a strange place but hadn't realised that it should have been bolted to the front of the engine. My friend said it didn't matter where it was as long as it was a good ground.
He also mention that he had come across this problem before i.e the engine harness ground not being reattached after the timing chain cover had been removed for timing chain tensioner replacement.
I had checked this ground and it seemed to be okay. But this morning with the engine running I re checked the end of the bolt and still got over 12 volts. So I decided to slacken it off and the engine stopped immediately.
I have now cut the wire back to the length it would have been and reattached it to its rightful place on the timing cover. Went for a test drive and all seems to be okay.
Keeping my fingers crossed as I start to rack up some mileage
10-10-2018, 09:32 AM
Or was it me disturbing the wires under the turret.
