If the timing chain stretches on one side of the engine, is it possible for the symptoms to show up on the other side?

 

What car?

What symptoms?

What makes you think that you might have a stretched chain on one side and not the other?

 

It is a 2002 x-type 3.0

I took the camshaft covers off and the chain for the left hand side I can move side to side on the intake cam sprocket. and when i push down on the chain between the two sprockets, the intake cam rotates slightly. It shouldn't turn much at all if the chain is tight right? It feels like i could just about get it to skip a tooth as well. The part that gets me, is the codes I am getting are 301 303 and 305 which are for the odd cylinders. And when i took the manifold off, there is quite a bit of black gooey buildup on that side. The timing chain on the right side of the engine is pretty firm all through out its revolution. That's where I am getting confused. So I'm kinda wondering with the VVT and camshaft advance business, is there something that could cause the right side of the engine to be showing the symptoms of a problem on the left side? I appologise if I'm misunderstanding some of these terms or concepts, but I'm trying to learn as much as I can as fast as I can. Thanks for your response test point

 

Let me help you out with a couple of things on the AJV6. First, let's get the lefts/rights correct. When standing at the BACK of the motor (which is actually standing at the left fender), the right hand bank is right/left hand bank is left. Even though you'll now be standing in front of the engine and facing the timing chains, the bank on the left side is actually the right hand bank, etc. Also, when facing the front of the engine and looking at the timing chains, this crankshaft runs clockwise. It is IMPORTANT not to turn the crankshaft counterclockwise, even by hand because it loads both timing chains on the wrong side of the tensioners.

The AJV6 uses two timing chains, both driven off the crankshaft and one for each bank, driving continuously both the intake and exhaust cams. This engine uses a LOAD/LOCK chain tensioner with two skis. Inspect BOTH skis to ensure they're still intact. Both the boomerang one and the straighter one. If they've disintegrated (which can happen) the load lock chain tensioner will probably be extended past its service limit causing the slack in the chain. Next, check the tensioners. Both tensioners should be rigid. You should not be able to compress them. If one does, then the ratchet device on that one is broken and needs to be replaced.

Next, check verify the timing of both banks is correct. Look for a timing mark on the crankshaft and a timing paint dot on each of the four sprockets (two pairs). Work first on the RH bank (on your left facing the chains). With the crankshaft in about the 7/8 O'Clock position, count clockwise, 23 chain links to the white dot on the exhaust sprocket, then 15 links to the dot on the intake sprocket. If you get both 23 and 15 then you're timed correctly. Do the same thing with the LH bank, rotating the crank to about the 5 O'Clock position only counting counterclockwise - same - 23 links to the exhaust cam, then 15 to the intake.

If everything is OK with the tensioners and skis and the timing is correct as above, then we'll need to start again on something else.

 

The chain tension is a function of two things; the oil pressure activated tensioners and the spring pressure of the valve springs acting on the cam lobes. I have no experience to comment on the static slack or lack thereof of the chains in some unknown position. The proper way to align or check the alignment of the cams is with the cam lock down tool and a pin in the flex plate alignment slot.

Here is the OBD code chart for the P0300 series with a list of things look for. I would suspect that they are in some general order of probability.

 

Sorry, can never seem to get the 'attach' and 'send' buttons in the right order.

 

TP - This is an X-Type with a duratec V6, competely different valve train arrangement than an AJV8. See my reply #4 above yours.

 

Steve11 is there any way to do what you suggested without taking the engine out of the car? I think the main thing I'm trying to avoid right now is taking the engine out unless absolutely necessary. Thank you guys for all your help so far. Also, is it a possibility that something is causing the right hand chain to be to tight? Sadly I'm about to buy a new car and give up on the X. I don't mind spending the hours in labor, it's the dollars I'm trying to avoid as much as possible. I don't have an engine hoist or the equipment to pull the cradle out the bottom so any in-car diagnosis I can do is key. Thanks!

 

The information I gave you can be done with the engine in bay, the front cover has to be removed though. I described the process of checking/verifying valve train timing because you asked the question concerning timing and skipping a tooth. I highly doubt that is the case, but I described the logical process for you, necessary to verify timing on the AJV6. That said, I've never seen a timing chain skipping a tooth on this engine, but I have seen defective tensioners and damaged/destroyed chain skis.

Rotate the crankshaft CLOCKWISE and stop in several places, check for slack, see if the chain slack disappears and reappears on both sides, if so, that is a little more normal and expected. If it is continuous and only on one side, then I'd be a little concerned about that tensioner. Obviously, it is very difficult to diagnose something like this over the internet.

All in all, none of this is probably causing the P0301/3/5 misfires which are all of the right bank cylinders. These are the cylinders that are impossible to reach because of the intake manifold interference. I've seen DIYers only change the outside three spark plugs (e.g.) meaning that the back bank gets neglected. I'd focus on: Plug condition, wiring harness, coils.

 

I've replaced all 6 plugs and coils numerous times in the last 6 months. Tried 3 different kinds of plugs too. I highly doubt that the problem is that simple as much as I wish it was The two timing chains do not feel similar to eachother in terms of tension throughout revolutions of the crankshaft.
The timing chain on the odd cylinders seems to be in much better condition and have a much more consistent state of tension. Maybe the left timing chain needs to be replaced and is about to go bad, and the right chain is perfectly fine and timing is not my problem. I can actually twist the left timing chain quite a bit at points. There are the proper number of teeth between the camshaft marks. I will be buying a tool to remove the pulley on the crankshaft and attempt to remove the cover to see how the links line up there. I think I'm leaning more towards the catalytic converter being clogged, or not working well enough anymore since the wiring harness seems to be intact and working properly. The cylinders are all three firing normally as far as i know at idle, but the higher the rpm the rougher the engine. The excess oil in the manifold is probably because of blowback caused by excessive back pressure. That's my guess anyways. Is there a way to take the belt off without using the "special tool" mentioned in JTIS? Thank you again for all your help.