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So Bank 2 is a disaster. Your STFT maxes out for much of the video. Guess which bank Coil #6 is? That right! Bank 2.
You seem to have at least 2 problems.
The second problem is your long term trims are both high at 8. You either have a vacuum leak (remember the post I made about blowing smoke into the intake?), or your TPS is bad. If your mechanic friend is so inclined, ask him to make sure there are no vacuum leaks, especially check around the intake manifold. Long term trims indicate that you have a leak somewhere. With the way the oxygen sensors are looking, you could have a major exhaust manifold leak perhaps? Take that shield off and see what things look like before the lambda sensors. No one cares about anything after that, as it won’t affect anything the engine sees. I suspect it’s the intake manifold though, IF there’s a leak.
I had an issue where my long term trims we’re constantly in the 7-10 range, and it was the Throttle Poteniometer Sensor, even though it was bench testing perfectly. It is an expensive part, but as soon as I replaced that, my long term trims dropped to zero.
Hey, i will try to checkout everything on the weekend, i think the new coil will arrive today.
But I have a question: didnt a positive ShortFuelTrim means that its to less Fuel in the mixture, so he trys to make it more "rich"?
I dont know, because i changed the coil with the crack today to cylinder one and the coil of cylinder one to cylinder six, so the problem in ShortFuelTrim should go to bank1? But it didnt, everything stayed the same, Bank 1 was "okay" but Bank 2 maxed out.
The way the coils work is that power is always sitting or present on the coil and when the ECU provides a timed ground for each individual coil there will be a current flow in the coil to give a spark
The individual ground wire to the ECU is:
Last edited by Lady Penelope; 03-01-2019 at 04:37 AM.
Hey, i will try to checkout everything on the weekend, i think the new coil will arrive today.
But I have a question: didnt a positive ShortFuelTrim means that its to less Fuel in the mixture, so he trys to make it more "rich"?
I dont know, because i changed the coil with the crack today to cylinder one and the coil of cylinder one to cylinder six, so the problem in ShortFuelTrim should go to bank1? But it didnt, everything stayed the same, Bank 1 was "okay" but Bank 2 maxed out.
Best regards
Frederik
Frederik,
Lets work on the problems we know first, and then we can attack what comes next. Let’s not worry about short trims. Those should be constantly shooting above and below zero, constantly adjusting the fuel ratio to get to the perfect ratio. If your torque app is anything like mine, the reader only takes a reading every second or two, so it’s not really the best tool to use to track short trims. You would need something reading the trims constantly and graphing it. Long term trims will move of the car is driven enough.
Id like to see a p0301 code thrown now that you’ve moved the coil over to Cylinder 1, but these cars are not generous with the codes. I’m assuming all your cylinder and coils are dry?
By the way, the MAF appears fine, as does your coolant sensor. The fact that Bank 2 is bad and Bank 1 is better, or at least different....I have to involve the exhaust manifold now. Perhaps the oxygen sensor for Bank 2 is bad? There’s nothing on the intake side that would differentiate between banks, so we won’t find anything catastrophic there.
Heres what we can do. Switch oxygen sensors to see if the LTFT start to go up in Bank 1 and start to move down in Bank 2. That could rule out the oxygen sensor.
I don’t know if you have a catalytic converter, but a blockage there could cause this issue.
Finally a major leak in the exhaust from the Bank 2 exhaust manifold up to the oxygen sensor joint. Anything after that is no longer metered. If you remove the shield covering the exhaust manifold, do you see any massive cracks? Can your mechanic check for leaks on that end?
Lastly, have you checked the ECU plugs for corrosion? This is a common issue and easily resolved no less! When you unplug the red and black harness, your looking for a bright green coating. Spraying those pins down with an electric contact cleaner isn’t going to hurt anything even if you don’t find anything wrong.
I think the biggest clue to chase right now is how Bank 2 is very different from Bank 1.
Ive chased a lot of issues with my engine, and I was able to get it back to a LTFT of zero. I’m not sure if everything I did was necessary (I did throw a lot of parts at the car) but I learned a lot in the process!
Lets work on the problems we know first, and then we can attack what comes next. Let’s not worry about short trims. Those should be constantly shooting above and below zero, constantly adjusting the fuel ratio to get to the perfect ratio. If your torque app is anything like mine, the reader only takes a reading every second or two, so it’s not really the best tool to use to track short trims. You would need something reading the trims constantly and graphing it. Long term trims will move of the car is driven enough.
Id like to see a p0301 code thrown now that you’ve moved the coil over to Cylinder 1, but these cars are not generous with the codes. I’m assuming all your cylinder and coils are dry?
By the way, the MAF appears fine, as does your coolant sensor. The fact that Bank 2 is bad and Bank 1 is better, or at least different....I have to involve the exhaust manifold now. Perhaps the oxygen sensor for Bank 2 is bad? There’s nothing on the intake side that would differentiate between banks, so we won’t find anything catastrophic there.
Heres what we can do. Switch oxygen sensors to see if the LTFT start to go up in Bank 1 and start to move down in Bank 2. That could rule out the oxygen sensor.
I don’t know if you have a catalytic converter, but a blockage there could cause this issue.
Finally a major leak in the exhaust from the Bank 2 exhaust manifold up to the oxygen sensor joint. Anything after that is no longer metered. If you remove the shield covering the exhaust manifold, do you see any massive cracks? Can your mechanic check for leaks on that end?
Lastly, have you checked the ECU plugs for corrosion? This is a common issue and easily resolved no less! When you unplug the red and black harness, your looking for a bright green coating. Spraying those pins down with an electric contact cleaner isn’t going to hurt anything even if you don’t find anything wrong.
I think the biggest clue to chase right now is how Bank 2 is very different from Bank 1.
Ive chased a lot of issues with my engine, and I was able to get it back to a LTFT of zero. I’m not sure if everything I did was necessary (I did throw a lot of parts at the car) but I learned a lot in the process!
I will take time to do it on saturday, but today i can try to change the oxygen sensors, do i have just to switch the plug or do i have to change them completly, get them out and switch one with the other?
ECU is one of the things on my list i want to look for, but i have to write it down, there is so much i have to look for so i have to learn alot while doing it.
Actually there is no code on the car, in my entire ownership she never have put down any Code.
Coil 6 had a bit of oil on the side, but it was just a very very small amount, the hole with the spark plug looks dry, so no oil standing inside of it.
Sorry for me taking such a long time, but most things on a car are very heavy to understand for me, so it takes longer for me to set the things up that you all told me, sorry for that. Thanks for your patience
What i found: in Torque (im not realy familiar with this app, but i start to learn things) i found the Option for the oxygen sensor voltage: bank 1 is jumping up and down and bank 2 is just flat without any reading it not shows anything just 0 volts, i will try to swap them both to see if something happens
@Vee suggestion of swapping the Bank 1 and 2 O2 sensors is a good idea. You will need to swap the complete O2 Sensor. You must not just swap the connectors - bad things will happen.
Before you do that though I would do the check for cracks in the exhaust manifold. It is a 5 minute job to remove the cover from the manifold and see if there are any cracks. Start the engine with the cover off and see if there is any noise or leaks coming from the manifolds or joints.
Checking the ECU connector is also easy and quick. It's in the passenger's side footwell. (You guys have the driver on the left side, correct?) Theres a red and black connector to it. Make sure you have a 10mm deep socket to take the ECU off. It's just easier to plug and unplug with the box off and out of the car.
I just want you to unplug it and check for green corrosion and then spray with electrical contact cleaner anyways.
Yes we have the Driver side on the left ECU stands No.1 on my list I bought electrical connector spray today, i will look closley if there is any corrosion or if something is wet.
Will dismount the heatshield and look for cracks.
I have read about to change the oxygens... My first thought about just change the connectors was pretty dumb *facepalm*
I will let you all know about what i could find tomorrow...
- checked ecu, everythings fine, not a bit of corrosion and the plug grabs every pin very good. I applied a small amount of the connector spray.
- oxygen sensor number 2 is now working, it had a bit of corrosion but with the connector spray it started to work and now both banks are jumping between +7 to -7% short term fuel trim...
- long term fuel trim is still high on +8% and it didnt move
- exhaust manifold has no crack i watched from the top and from the bottom as far as i could looked.
- i have checked the intake side with cigarette and the only thing where smoke comes out was the area on the throttlebody...
- sadly the ignition coil didnt arrived today, maybe on monday
She runs alot better now, but in idle she is slightly rough.
Is there a sealing from the throttlebody to the intake manifold?
Oddly enough, no. There is no gasket or sealant between the throttle body and intake manifold. Strange but true. It’s metal to metal.
It will take awhile for the Long Term Fuel Trim to adjust. The fact that both sides are jumping is excellent progress. I suspect you’ll have LTFT on both sides matching in a week or two.
You mentioned that there was smoke coming from somewhere on the throttle body? When you seal off the MAF, there shouldn’t be smoke coming from anywhere. You did this with everything fully together? The throtttle body butterfly is clean, right?
The idle may smooth out as you drive, but assuming both banks carry a LTFT of 8, we still have a problem on the intake side. Fixing the oxygen sensor will likely eliminate issues on the exhaust side.
You may have a faulty TPS, which is an expensive part.
So i put a plastic bag on the MAF, fixed it with cableties and ducktape.
Some smoke comes from the throttlebody but its not that much, but as i fixed the oxygen connection i have seen some oil on the back of the valvecover and head. So on cylinder 6.
I forgot to look at this place if smokes comming Out, but from that point was a clear whistle noise when i pushed smoke in the intake! I redid everything now, because i wanted to look closely at this point.
The valvecover gasket throwed alot of smoke out on that, but its heavy to notice if u dont put light directly to it.
I think thats the problem, because cylinder 6 is the worst running.... I will fix that first before thinking about a new TPS i think
Ok, let’s hold off on that TPS until all other possibilities are investigated.
Any smoke would be bad from the throttle body as all other joints should be sealed. That will eventually need to be addressed, but I agree, take care of Cylinder 6 first.
I change the Valvecover Gasket during the next weekend.
The engine runs pretty smooth the last days, not perfect but its acceptable, maybe if i change the gasket it will run a bit better. Long term fuel trims didnt move till now, but i think i will find a solution.
When i cold start the car theres a slight knocking noise, i dont think its from the chains, but it sounds pretty metallic, so i think maybe its a valve or something. Its away when the engine is in normal operating temperature. Can i check this or do i have to take it to a specialist to take it apart?
Make sure you change the six spark plug well gaskets as well. If you're changing the camcover, make sure you get those 6 gaskets as well. You may need the bolt gaskets as well, part NBC2575CA....13 of them!
Make sure you change the six spark plug well gaskets as well. If you're changing the camcover, make sure you get those 6 gaskets as well. You may need the bolt gaskets as well, part NBC2575CA....13 of them!
No problem, thank you Vee, i got all 13 for the bolts, and in Germany they mostly sell a set of valvecover gasket with the spark plug hole gaskets.
I thought its better to change everything together than to open something because I am to lazy and have to open it again.
I change the Valvecover Gasket during the next weekend.
The engine runs pretty smooth the last days, not perfect but its acceptable, maybe if i change the gasket it will run a bit better. Long term fuel trims didnt move till now, but i think i will find a solution.
When i cold start the car theres a slight knocking noise, i dont think its from the chains, but it sounds pretty metallic, so i think maybe its a valve or something. Its away when the engine is in normal operating temperature. Can i check this or do i have to take it to a specialist to take it apart?
Hey sir, how is this? Been reading this whole thread as this looks a lot like the problem i also have! Have also changed a lot of things with no luck
Mine also does that knock on idle, i hava also noticed it seems cyl6 because when i remove the ignition coil plug nothing happens, changed coils and nothing, weird thing is it sparks and spark plug is burning fine
so there was a fault on cylinder 6 one valve was damaged, caused the knocking noise. The car is now off the road, im not totally done with what to do with this beauty, because the cheapest workshop i could found wanted 2500 Euros to fix it. I had alot of trouble with that car the whole ownership...
Everyday when i drove her it was like: "wow what is breaking next"
I sadly have to say i had very very bad luck.
Maybe one day i will fix her or buy a new one, but for now im without a Jag
so there was a fault on cylinder 6 one valve was damaged, caused the knocking noise. The car is now off the road, im not totally done with what to do with this beauty, because the cheapest workshop i could found wanted 2500 Euros to fix it. I had alot of trouble with that car the whole ownership...
Everyday when i drove her it was like: "wow what is breaking next"
I sadly have to say i had very very bad luck.
Maybe one day i will fix her or buy a new one, but for now im without a Jag
Greetings
Frederik
Very sorry to hear that! So your knocking noise was not only at idle, a valve makes noise all the way through the rpm range, right?
Very sorry to hear that! So your knocking noise was not only at idle, a valve makes noise all the way through the rpm range, right?
The knocking is there all the time, sometimes louder sometimes not so loud. But its louder when engine was cold... So i didnt hear it all the time cause the engine itself got louder over weeks, not much, but to much for a Jag...
Did u miss performance? Did you have tested the compression on all cylinders?
When u can try to get some obd readings for the fuel trims and so on. The people here helped me alot to learn about this readings and how to understand them.
Check coil again
Check if the valve cover gasket is fine and no oil is leaking to the sparkplug in cylinder 6
I can tell the first time i heared the knocking noise i thought it was the timing chain cuz it wasnt present all the time. A good Workshop can check compressions and look in the cylinder with a small camera to see if there is any damage.
The knocking is there all the time, sometimes louder sometimes not so loud. But its louder when engine was cold... So i didnt hear it all the time cause the engine itself got louder over weeks, not much, but to much for a Jag...
Did u miss performance? Did you have tested the compression on all cylinders?
When u can try to get some obd readings for the fuel trims and so on. The people here helped me alot to learn about this readings and how to understand them.
Check coil again
Check if the valve cover gasket is fine and no oil is leaking to the sparkplug in cylinder 6
I can tell the first time i heared the knocking noise i thought it was the timing chain cuz it wasnt present all the time. A good Workshop can check compressions and look in the cylinder with a small camera to see if there is any damage.
Yes i check compression is good on all cyl and performance is good as always has been
i got an obd2 reader but cant understand nothing about the fuel trims, i must do it again and post here the reading to see if anyone can help me understanding them.
valve cover has a small leak but the spark plug seems to be burning fine at least judging by the colour
03-01-2019, 02:39 AM
so i have to learn alot while doing it.
