Misfires when warms up 2012 v8 NA
#21
#22
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An update given to a SSD guy he did check all the electricals and run SSD he said car is clear electrically and their is nothing in SSD and suggested the problem in mechanical and advise open the and check cylinder so like open the engine. Don't want to go that any other suggestions will really appreciate
#23
#25
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The only advice I had was when the description of your problem appeared similar to what I had experienced and posted about in the post that I referred to.
I'm afraid that if it's a different problem, with additional indications such as backfiring, and having problems even when first started, I can't help with what it might be then.
If you did replace the HPFPs and it runs as bad or worse than before they were replaced, it's certainly not the same problem I had.
If you have not replaced the High Pressure Fuel Pumps, but if you have checked the fuel pressure at the rails, you can tell if it's a fuel pressure-related problem before spending the 900 (Durhams or dollars?) each to replace them.
If this is an engine that was damaged when you purchased it and had hopes of rebuilding it to full healthy operation, I have no idea what that would take.
I'm afraid that if it's a different problem, with additional indications such as backfiring, and having problems even when first started, I can't help with what it might be then.
If you did replace the HPFPs and it runs as bad or worse than before they were replaced, it's certainly not the same problem I had.
If you have not replaced the High Pressure Fuel Pumps, but if you have checked the fuel pressure at the rails, you can tell if it's a fuel pressure-related problem before spending the 900 (Durhams or dollars?) each to replace them.
If this is an engine that was damaged when you purchased it and had hopes of rebuilding it to full healthy operation, I have no idea what that would take.
#26
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Perhaps you may have already done this, but with the spark plugs removed, use a cooling system pressure tester to pressurise the system to 1 bar. If there is a drop in pressure, use a cylinder bore gauge to look inside each cylinder for any traces of coolant.
If there is coolant present in any of the cylinders, the head gasket(s) failed due to an overheating event.
If there is coolant present in any of the cylinders, the head gasket(s) failed due to an overheating event.
#27
#28
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I throw my penny on thoughts: You seem to have issue in one bank only, so i would focus on points that can cause single bank issues. The fault codes point to the coil circuits, but this can be only preprogrammed line. However: I would check the circuits by measuring with simple multimeter. Wires can be oxided under insulation.
Fuel injection and timing of spark are are adjusted by the measurement value of lambdas. Lambdas do stay open loop until they and engine are heated up. Lambdas do wear and once failed they can sent wrong measurements -> injection and timing are set wrong after the engine are heated up and lambdas enter closed loop.
Not sure if both banks have own fuel rail pressure sensors? If yes, failed sensor can sent incorrect data what can cause too high pressure (rich mixture) or too low pressure (lean mixture).
An airleak could cause similar issue, but normally would not only effect in one bank. Cam timing error in one bank: Possible. NA engines have variable timing camshafts. Stuck cam timing actuator? Not sure if both banks have cam timing sensors?
Lambda failures are quite common, and they are worth to change time to time, for correct measurements, i would start with them (typically four, but minimum for the bank giving issues) and measure the coil wires of that bank.
I hope this help.
Fuel injection and timing of spark are are adjusted by the measurement value of lambdas. Lambdas do stay open loop until they and engine are heated up. Lambdas do wear and once failed they can sent wrong measurements -> injection and timing are set wrong after the engine are heated up and lambdas enter closed loop.
Not sure if both banks have own fuel rail pressure sensors? If yes, failed sensor can sent incorrect data what can cause too high pressure (rich mixture) or too low pressure (lean mixture).
An airleak could cause similar issue, but normally would not only effect in one bank. Cam timing error in one bank: Possible. NA engines have variable timing camshafts. Stuck cam timing actuator? Not sure if both banks have cam timing sensors?
Lambda failures are quite common, and they are worth to change time to time, for correct measurements, i would start with them (typically four, but minimum for the bank giving issues) and measure the coil wires of that bank.
I hope this help.
#29
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As I understand, your XJ has been broken since the day you bought it, when you first posted on February 21:
Sticky or low brakes - Jaguar Forums - Jaguar Enthusiasts Forum
including one about overheating:
Overheating - Jaguar Forums - Jaguar Enthusiasts Forum
And several other threads you've created about it.
Not starting help!!! - Jaguar Forums - Jaguar Enthusiasts Forum
Engine repair or part the car - Jaguar Forums - Jaguar Enthusiasts Forum
If I recall correctly you've started a couple of threads trying to figure out what the problems are, and have tried just about everything suggested.
This thread doesn't include all the info from your other threads, and looks like it's echoing suggestions that forum members have provided previously.
Sticky or low brakes - Jaguar Forums - Jaguar Enthusiasts Forum
including one about overheating:
Overheating - Jaguar Forums - Jaguar Enthusiasts Forum
And several other threads you've created about it.
Not starting help!!! - Jaguar Forums - Jaguar Enthusiasts Forum
Engine repair or part the car - Jaguar Forums - Jaguar Enthusiasts Forum
If I recall correctly you've started a couple of threads trying to figure out what the problems are, and have tried just about everything suggested.
This thread doesn't include all the info from your other threads, and looks like it's echoing suggestions that forum members have provided previously.
Last edited by 12jagmark; 06-25-2023 at 08:33 AM.
#30
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Hey guys thank you all for the suggestions. I am trying to fix it as much as possible. As jagmark said I have done alot on the car. So somehow fixed the engine back as per my previous posts on the form as jagmark mentioned.
Just changed the high pressure fuel pumps as suggested but it's still the same. I will upload a video of it and share a link. Any thoughts will be appreciated
Video link
https://youtu.be/Zc20jW04N6Q
Just changed the high pressure fuel pumps as suggested but it's still the same. I will upload a video of it and share a link. Any thoughts will be appreciated
Video link
https://youtu.be/Zc20jW04N6Q
Last edited by Abbas_ahmd; 06-28-2023 at 10:01 PM.
#31
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Update: fixed
As stated above it was firing sequence issue with cam on the right back. However if anyone any issues like this and if you have repaird your head. First thing to do is checking the bloody firing order. Took a while but however thank you to all supporting members of the form
As stated above it was firing sequence issue with cam on the right back. However if anyone any issues like this and if you have repaird your head. First thing to do is checking the bloody firing order. Took a while but however thank you to all supporting members of the form
#32
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