Hello all. I've been reading posts all afternoon and it's time to ask for some help. In four different trials I am consistently getting P0300, P0301, P0302, P0303, P0304 codes. I start the car and there is a hard ticking noise heard from the engine intermittently and at 1 minute "restricted performance". Here's a video of this performance. https://vimeo.com/187911683/c16743102b

This is a 2002 XJR (127k miles / VIN MF41384) and I found some advice that might apply.

there are really only two issues that will affect one bank only: Bad O2 sensor and exhaust cam timing.

A guess is that the ECM is trying to drive the throttle body lean to compensate for the Bank 1 rich condition which might explain the Bank 2 lean code.

I would start with pulling the bank 1 valve cover to check for cam alignment and tensioner condition. While there replace the tensioners if they are plastic. I don't know about the 3.2L engine but on the 4.0L the alignment is correct if the cam flats are almost in align but tilted to the center slightly. If found out of align it would be best to not start the engine again as you have jumped one sprocket tooth and survived. Jump another one and destroy the engine.

I recorded the OBDII port with my scanner and have placed the report here.

Questions -

- Is my O2 sensor bad?
- Could my exhaust cam timing really be off?
- Are my cylinders numbered like the left pic below or the right?

Thanks in advance. -Bill

 

The blinking check engine light is, I'm pretty sure, is what you say, the misses and ECM trying to work out the fuel flow.
My first thoughts are tensioners, guides and chains, I would not run the car again until you can determine this or you can do more damage. Taking off the valve cover and checking those would be my first point of this venture. Its quick and tells you a lot and doesn't require a lot of time. Also, since your there, I'd do a compression check. Be sure to check your plugs for gap and fouling since your showing the misfires.

 

@Highhorse. Thanks. I'll pull the valve cover off in the morning. Am I correct in thinking that needs to be the Bank 1 valve cover (as indicated in the pic of cylinder numbers I posted?) Does my VIN indicate below a 2002.5 or above?

(I cannot believe I have an above 2002.5 engine because what are the odds I would have consistent #1 through #4 cylinder misfire ACROSS from each other on two different banks of cylinders. That would be insane.)

Did anyone happen to read the PDF of my scanner record? I'm not sure how to read if the O2 sensors are working.

Thanks. -B

 

Blinking MIL = misfires so dire they're damaging the cat(s). Do not keep causing it if it occurs!!

 

I'm not thinking you would get those problem with a failed O2 ... and the car would give you a failed O2 code.

The blinking CEL indicates (in all vehicles) that the misfire is bad enough to cause unburned gasoline to be flowing to the cats ... you don't want this as the gas will ignite in the cats .. raising the temps enough to destroy the internals. Never run a car with a blinking CEL.

Due to the common tensioner issue -- any sounds must be investigated with a valve cover removal. You make have lost a tensioner - and the chain loose enough for it to have skipped a tooth.

 

What a mess. I can't believe it even ran. Next steps?

 

Take the head off. The pistons are probably damaged, but the head is almost certainly destroyed.

 

Is there any harm in removing the exhaust cam and then performing a compression test on each cylinder in hopes of being the luckiest non-bent-valve person that ever lived?

 

Don't believe you can have any safe zone with an interference engine. At some place the top of one of the pistons hit a valve ... they don't take kindly to that.

Used heads are available -- it's a question of piston damage. Do you have a good independent?

Price out the best possible situation -- that will give you a starting point. If the car is not worth that expense .. it's time to look elsewhere.

At least this is another indication of the incorrect theory of the 9/01 changeover to metal vs later update of plastic.

 

Maybe send a private message to Motorcarman -- you need to have someone who understands and has played with multiple cars. He may tell you the best way to proceed without doing additional damage.

You can also use an inspection camera through the spark plug openings --

 

I ordered a 7mm wide USB camera to take a look at the pistons. Thanks for the advice. Please stand by for more exciting video.

 

STOP!!!!!!!!!!!!!!!!!!! You are NOT the luckiest person if the vales are not bent. You are one of the about 50%.

Remove the exhaust cam and perform a compression test. I have a 1999 XJ8L that I bought for $500. One of the secondary chains broke and the owner did NOT want the car anymore.

I pulled the exhaust cam and performed a compression test. I got low readings but NOT ZERO.

I replaced ALL timing chains, guides, tensioners.

The engine is still running normally 5 years later.

The exhaust cam can stop in a safe place and NOT bend valves. This usually happens at a low RPM (idle).

When I worked at the dealer I found that the odds of bending valves when the secondary chain broke is about 50/50.

The intake cam does NOT stop rotating so you only have the exhaust cam stopped to worry about. It CAN stop in a HAPPY PLACE.

Diagnose before you start throwing parts at a car!!!!!!!!!!!!!!!!!!!!!!!!!!!
Don't blindly start repairing things that are not broken!!!!

When a light bulb burns out in my bathroom I don't rewire the house!!!!
Work from the simple end toward the disaster. (it might be simple)

bob

 

Thank you Bob, that is very encouraging advice. I'll pull the exhaust cam in the morning, check the compression and report back with numbers.

 

You might have bent valves but get away with removing only THAT head.
BROKEN valves are the real problem. They tend to destroy pistons and heads.

bob

 

About three years ago, Danielsand had a broken chain, with extensive write ups over three threads, but, as Bob notes, no other damage. Was able to fix and move on.

My local indy agrees with Bob, he told me over half of the engines were lucky. and it is luck!

 

Sorry I haven't been on to respond, family stuff, all good now. I see the cam flat is almost sitting TDC, maybe there is a bit of "luck"?....fingers crossed Pricebill.

 

I pulled the exhaust cam and executed a dry compression test on all four cylinders. About 130 across all four. I felt so encouraged by these numbers I machined two pieces of 1" square metal bar to provide cam lock once I position the engine at TDC. Now all I need is a couple of metal tensioners and at least ONE replacement chain.

I purchased a kit via eBay and it arrives in the morning. Here's a link.

JAGUAR V8 2001-2009, UPPER SECONDARY "UPDATED" TIMING CHAIN TENSIONERS w/CHAINS | eBay

It goes together like a bicycle chain around the secondary gears. I can't imagine anything more ridiculous to keep this engine running forever but certainly good enough to determine if I'm the owner of a grenade.

Here is my plan; please assassinate at will.

- Hand rotate engine to TDC. Bolt on (homemade) cam locking tool on left bank.

- Bolt on (homemade) cam locking tool on right bank with care.

- Install new tensioner on right. Leave pin in.

- Do everything above but now on the left. Pull pins to have the tensioners take up the slack on secondary timing chains.

- Hand rotate engine to see if I have done everything really wrong and stupid.

Did I?

 

The timing is not set from TDC. It's something like 70 deg. Some one will be along with the correct number. There is a lock pin used on the flywheel through the CKPS hole.

 

The crank is set at 45 degrees AFTER TDC when the cam flats are aligned!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Please consult the engine repair course before you set the engine timing incorrectly and actually BEND VALVES!!

bob

 

I suppose I should have indicated I will be following this set of instructions (Tmingi chain and tensioner replacement).