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1995-2002 Range Rover P38A
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Discussion Starter #1
Hello guys, I have been back and forth about this irritating ticking noise coming from my 4.6L.
I can upload a video if it helps, but it is a tapping/ticking noise that is prevalent all the time the motor is running and it gets louder when driving as you accelerate. However, when i'm parked and i rev the engine it seems to almost disappear around 2,000rpm. I went to a local mechanic and they told me it was my exhaust manifold, and I haven't been able to find one to replace it, and last week I decided to take the car to the local LR dealer. They were confident the issue is the head gasket. I then decided yesterday to give the head gasket sealer a go, I used the Bar's leak HG-1 solution. So far i haven't noticed any difference, however it's only been a day and I followed the instructions the best I could. I'm just looking for advice from anyone else who has had a blown head gasket with a similar noise problem, or fixed a tapping/rattling P38 engine noise. It is very loud from the passenger side (LHD) towards the lower half of the motor.
Any input is greatly appreciated as i've grown to love this car since I got it and I don't wanna be stuck having to spend several thousand just to have it run properly again if I can help it. :sad:
Cheers
 

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Bars Leak will only have any affect if the head gasket is blowing into the coolant passages, otherwise all it will do is clog the radiator and heater matrix (although it will do that anyway). If the cooling system is pressurising and the car is overheating then it could be a blown gasket on one of the end cylinders as they are the only ones with a coolant passage running past them. If it isn't and it is just the noise, then the head gaskets are fine, or at least they haven't blown into a coolant passage. How long has it been like it for? A friend's car was very similar for over a year and it sounded just like a blow between the head and exhaust manifold. He replaced the gaskets and that made no difference, he then thought it was the manifold itself with a crack so took that off and checked for a leak by filling it with water. No leaks there either. Finally it got much worse and he bought it to me. Still running fine but making a hell of a noise (https://www.youtube.com/watch?v=dKEqPY5rX7A) and from underneath when revved, you could see little bits of red hot gasket being blown out the head to block joint.

WP_20181110_13_06_52_Pro.jpg

As there are no coolant or oil passages in that area, there were no other signs and it was even still running on that cylinder. A compression test might have shown that it was down on that pot but one cylinder down on compression could be any number of other things so not immediately conclusive.
 

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1995-2002 Range Rover P38A
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Discussion Starter #3
Richard,
I have not had any issue with the cooling system in the truck. It has always stayed at normal temp and the coolant in the system is pure and clean, same color as in the bottle. It's been since December 28th. I was on a road trip one day and noticed the sound at one point whilst driving. Since then, I can say it has become louder.
 

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Definitely sounds as though you have the same problem. I've also know them to blow upwards into the Vee and in that case the noise is far louder with the oil filler cap off. Initially you would only have noticed it when the car was pulling under acceleration but then gets worse so is there all the time? You should be able to identify the offending cylinder by pulling the plug leads off one at a time. Or get underneath it in the dark and get someone else to rev it and look for something looking like a spark. You may even see a flame coming out of the hole. The fix is simple enough if you do it yourself, plenum off, lower inlet off, exhaust manifold off, head off. Chances are the head will need a light skim as it will have burnt the face where it has been blowing, but other than that you are only looking at the cost of a gasket set and head bolts.
 

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Can it be lifters?

You can put a vacuum hose in your ear, works very good as a stethascope, and go with the other end along the cylinders, if it is a head gasket you should be able to hear a difference somewhere.
 

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1995-2002 Range Rover P38A
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I think what you should do is a cylinder leak down test. The gauges are actually pretty reasonably priced, and plenty of youtube videos to walk you through the basics. Even quicker than that, would be a compression test on all cylinders. Don't ever trust or believe any head gasket sealer. The only fix for a bad head gasket, is a new head gasket in my opinion.
 

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Drain it, back flush the whole cooling system and hope you get most of it out or you'll be looking at a new radiator and heater matrix at some point in the near future to cure the overheating problem.
 

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I haven't had this issue on my Rangie, but on two previous vehicles I've had the noise that I think you're describing. In both cases it was loose exhaust manifold bolts. Tightening them stopped the noise. If this is your issue, the longer it goes, the more likely you will need to actually replace the manifold gasket, as the gases leaking past it will eventually destroy it. If you're lucky (as I have been), it will be as simple as this.
Harv
 

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Mine started with the squeak under load a couple of months ago, and then after a few hundred miles went the full chuff chuff last week. LH bank, I haven't spent too much time diagnosing where, I'll find out soon enough.
I'm decapitating her this w/e.
 

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That's just how my mate's car started off. A squeak that he initially though was a propshaft UJ which then got progressively worse.
 

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1995-2002 Range Rover P38A
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Check your exhaust studs for tightness and the gaskets for leaks.
 

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1995-2002 Range Rover P38A
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p38rangebryce,

I have this same issue on my 2001 RR 4.6L. I have still have no idea what it is. I have gotten some responses on my own thread about it maybe being a rod that has gone out. I don't think I have heard the exhaust manifold one before, but that seems like it is totally the wrong thing. Maybe we can both get some insight and help with this! ;)


Best of Luck!
Pulaski
 

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If I remember right, your previous thread stopped when you were asked what you meant to a rod having gone out. The only time I've known a rod 'go out' was when it was sticking out of a hole in the side of the block.
 

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Hate to admit this, but years ago I used Bars Leak type sealer (Don't remember the brand anymore) on my P38. This was before I was more proficient in DIY, so it was done mainly as an act of desperation.

Anyways, the sealer didn't really fix anything. In fact, within days, my radiator clogged up and almost destroyed my engine. I was able to move to the side of the highway before overheating really did its damage, but I still had to get a new radiator. Soon after, heater matrix produced a leak and as a result had to bypass it.

Looks like the OP already used the product, so I would keep an eye on the cooling system.
 
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