Auto Engineers in the house pls I need your advice; my 2003 toyota rav4 makes this rattling noise like diesel engine both when idle & when in motion and its also leaking oil seriously so we just have to keep toping the oil.

Our mechanic said its the chain adjuster which he later changed yet the rattling sound did not stop also he said d leakage is from the chain sprocket which he sealed yet it didn't stop leaking, we took it to another mechanic who assuredly told us that d camshaft is worn out& has to be replaced together with the pappet which he said is responsible for the rattling sound, d oil leakage and the wobbling of the pulley driving the camshaft.

Your engine parts have funny names please what is pappet?

Amono: Your engine parts have funny names please what is pappet?

Its either tappet or pappet that he mentioned.

CMGO:

Its either tappet or pappet that he mentioned.

What is the engine type of the rav4?

lomomike:
What is the engine type of the rav4?

1aZ

Go get that car scanned with an OBD ii scanner first DON'T let the mechanic open the engine or remove any component yet. When the car is scanned, post the codes here and we will gladly help direct you on what to do about the repair so as to prevent expensive fixtures and unnecessary part replacement.

That sound is more of a mechanical sound. Firstly let them trace oil leakages. Make sure a thorough visual inspection is done. As for scanning its not a bad idea. But a scan would never reveal any sound of such. I fink your camshaft sprokets aare worn out alrdy and this was as a result of shortage of oil. Lastly when last was the car serviced and what type of oil do you use??

lomomike: Go get that car scanned with an OBD ii scanner first DON'T let the mechanic open the engine or remove any component yet. When the car is scanned, post the codes here and we will gladly help direct you on what to do about the repair so as to prevent expensive fixtures and unnecessary part replacement.

Ok, will try and get it done

mayor2013: That sound is more of a mechanical sound. Firstly let them trace oil leakages. Make sure a thorough visual inspection is done. As for scanning its not a bad idea. But a scan would never reveal any sound of such. I fink your camshaft sprokets aare worn out alrdy and this was as a result of shortage of oil. Lastly when last was the car serviced and what type of oil do you use??

It was last serviced in may, I use mobil xhp but plan to change to synthetic when the oil stops leaking.
D mechanic also suggested dat d oil pump be changed as it seems not to be supplying oil well to the camshaft

You can call 08165520837 or 08156087872 to get your car scanned

I need to ask if you recently swam through a pool of water as well. Cos if you did, you might have bent your valves which is why you get that diesel engine noise. Was your timing set right after the chain adjuster was worked on? Scan the car and see if you can pull any timing related codes. If you did not swim through a pool of water and your timing is okay, then i guess your intake camshaft actuator is bad. That is the source of the rattle. Depending on where you are, go to a spare parts village where they sell engines and get a tokunbo camshaft with the cam actuator (sprocket) for your engine. replace the existing sprocket. These sprockets go bad when they are starved of oil. Do not allow him adjust the tappets on that engine. They are not adjustable. Check and confirm that the oil control valve which regulates the camshaft actuator still works by applying 12 volts power to the terminal. If the plunger in the ocv moves then it is still good. if it doesn't move then u have the reason why ur camshaft actuator broke down. Change the OCV as well if it is bad or else you will be back to the mechanic to change the camshaft again. Make sure that the camshaft u buy is not for the 2AZ. Both engines look identical. The 2AZ is a 2.4 litre while your 1AZ is 2.0 litre. You might have to go with your camshaft. make sure your timing is set right after this fix or the noise will continue.

9icetoo: I need to ask if you recently swam through a pool of water as well. Cos if you did, you might have bent your valves which is why you get that diesel engine noise. Was your timing set right after the chain adjuster was worked on? Scan the car and see if you can pull any timing related codes. If you did not swim through a pool of water and your timing is okay, then i guess your intake camshaft actuator is bad. That is the source of the rattle. Depending on where you are, go to a spare parts village where they sell engines and get a tokunbo camshaft with the cam actuator (sprocket) for your engine. replace the existing sprocket. These sprockets go bad when they are starved of oil. Do not allow him adjust the tappets on that engine. They are not adjustable. Check and confirm that the oil control valve which regulates the camshaft actuator still works by applying 12 volts power to the terminal. If the plunger in the ocv moves then it is still good. if it doesn't move then u have the reason why ur camshaft actuator broke down. Change the OCV as well if it is bad or else you will be back to the mechanic to change the camshaft again. Make sure that the camshaft u buy is not for the 2AZ. Both engines look identical. The 2AZ is a 2.4 litre while your 1AZ is 2.0 litre. You might have to go with your camshaft. make sure your timing is set right after this fix or the noise will continue.

Thx 9icetoo, Never drove thru water, will find out if they set the timing right.
In one of your posts u stated that u once changed those components in ur vehicle, can u pls tell me d cost of each item just incase they need to be replaced. I stay in awka

CMGO:

Thx 9icetoo, Never drove thru water, will find out if they set the timing right.
In one of your posts u stated that u once changed those components in ur vehicle, can u pls tell me d cost of each item just incase they need to be replaced. I stay in awka

Scan first sha before you proceed with any repairs. I bought the camshaft with the actuator for less than 10,000. I bought it with the guarantee that if the noise doesn't stop, i will have them remove it and won't pay for the parts but labor. The OCV is about 5k. I have come across someone willing to sell the camshaft for 5k recently. Much depends on ur bargaining power. The labour should be around 8k. Do not use cheap labour, those cheap guys might not be able to set your timing right after the fix. Mgbuka obosi is close to you since you are in awka.

@Cmgo I see you are in good hands, just to add a little to what every one has said, I'm guessing your problem started out as a check light on your instrument panel, which you ignored cause there were no signs or strange noises from the engine to suggest a problem, gradually it deteriorated to where it is now, there's a reason cars are fitted with the "check light" it is a malfunction indicator, meaning every something is wrong with the car, not necessarily the engine but could range from suspension, to transmission to internal body electrical instruments. When we say go for a scan when your vehicle illuminates any of the warning signals: abs,airbags,check,vsc.........etc its just to help you ensure your vehicle does develop further problems. That said I will add a little to what 9icetoo said, there's a filter close to the ocv "pictures attached" when the filter gets clogged or blocked it starves the ocv of oil which could result in the excessive wear that lead to the leak you are experiencing, you also mentioned you mechanic said your oil pump needs replacement, ild advice you check your oil pressure light when the engine is hot and idling, if it flickers or stays on when the engine is running then oil pump might be bad, and in that scenario it will need to be replaced but in the absence of the oil pressure light on or flickering when engine is running don't touch the oil pump.

Focus on changing the camshafts and try and get a guarantee from the seller.

When you are done with all the repairs have the car scanned copy the codes down, have them cleared and re scan the car after using for about 50-100km.


Best of luck.

@ Gazzuzz, thx so much for ur contribution

The first pix is the filter located at the back of the engine behind the power steering pump (i presume the engine has the same identical layout as mine). The second pix is the OCV which is located just below the valve cover on the engine.

Hello friends, am glad to announce to you all that my car problem has been partly solved.

It took me this long because all efforts to scan the car with obd2 proved abortive until Gazzuzz came to my rescue using a scan tool (God bless u Gazzuzz).

The result of the scan revealed a faulty idle air control valve is and also the front airbag assembly and of course a retarded timing .

The oil leakage has been perfectly solved, my mechanic who also confirmed that the timing was retarded did set it right and the rattle sound disappeared.

This is the situation presently; each time he sets the timing the noise will stop but after a few days it will come up again and if I take it back to him he will discover that its either retarded or advanced and he would correct it. This has happened 3x.

Pls friends I need your advice.

I forgot to mention that the previous owner removed the factory fitted 1az ecu and replaced it with 2az ecu, I don't know if its responsible for the unstable timing.

I would first check the oil level. If the oil level is low or very dirty that would cause the timing chain to make noise. Next I would carefully listen with either a mechanics stethoscope or a long screwdriver to each accessory. To listen with a screwdriver just put the metal end of the screwdriver on the engine and your ear on the end of the handle. This is a surprisingly effective method of pinning down a noise. Just be sure to avoid the belt. See if any of the accessories seem to be making more noise than the others. Based on your description of the noise I would suspect the water pump. If you can not pin anything down that way you may have to remove the belt and run it to see if the noise is gone. If the noise goes away you can turn each component by hand to see if they are noisy. If the noise is still there with the belt removed it may be the timing chain. Listen at the front of the valve cover with your screwdriver. If the noise is there you likely have a timing chain issue. Hopefully this will give you some help in pinning down your problem. Noises are one of the hardest things to figure out from a distance.

Its possible your chain is worn. I don't know how possible it is for a 2AZ ecu to work with a 1AZ engine. Are you certain ur rav 4 has a 1AZ engine? Please look at the engine block and see what is written there. Also, download the pdf manual for setting timing on your engine. It will show you the normal length of your chain, how many links separate the camshafts and the postions of the markings on the chains when placed on the crankshaft and cam shafts. It will show you how to ascertain that the timing has been set correctly on your car. You can also do this with a scan tool. When you check live data on your car with a scan tool, it should display your engine timing with ignition on but engine off. My 2AZ shows 5 degrees with engine off and ignition on. Its also possible that the timing chain tensioner which uses oil pressure to function is failing and allowing the chain to slack a lot resulting in the messed up timing. This often happens when mechanics block the oil lines in the tensioner with gasket maker. Make sure this isn't what is happening to you.

Autosbay,

I don't think its an oil issue, as I recently drained the 20w50 oil that was there and refilled with 5w30 and its well gauged.

Thanks so much 9icetoo,

Yes its 1az engine as its inscribed on the engine block. The last time I checked the timing with a scan tool (though with the engine running it read 15.5 degrees) at that time the noise was already pronounced.

Will ask the mechanic to check the tensioner as you suggested

Read through your post, my suggestions are you replace your cylinder head, replace your timing chain, and get a brand new set of head bolts.


Doroboss.

doroboss:
Read through your post, my suggestions are you replace your cylinder head, replace your timing chain, and get a brand new set of head bolts.


Doroboss.

Thanks doroboss for your suggestion

CMGO:
Thanks so much 9icetoo,

Yes its 1az engine as its inscribed on the engine block. The last time I checked the timing with a scan tool (though with the engine running it read 15.5 degrees) at that time the noise was already pronounced.

Will ask the mechanic to check the tensioner as you suggested

With your engine running and the car fully warmed up(this means cooling fan has come on at least twice and temp gauge is somewhere around the middle), your ignition timing should be between 9 and 12 degrees (at least thats what mine is which shouldn't be too different from yours). I will attach a picture of the timing chain tensioner. Your mechanic should inspect the chain guides as well. If they are worn, they would also contribute to your malaise.

I just checked and your timing should be between 8 and 12 degrees after the car has warmed up. best of luck.

9icetoo:
I just checked and your timing should be between 8 and 12 degrees after the car has warmed up. best of luck.

Thanks a lot. The whole of the timing chain kit is in good condition although I had to tell the mechanic to set it right once more, will watch and see if that will make any difference.

Possibly tappet noise but it sounds like piston slap, worn bores.

AutosBay:
Possibly tappet noise but it sounds like piston slap, worn bores.

If was so it will persist even after setting the timing but in this case it doesn't.

It might be useful:

5 Common Engine Noises (and What They Mean)

1. Clicking and Tapping Sounds

An audible tapping or engine clicking noise coming from the front of your car will definitely draw your attention. Your ears will perk up and you will tune in to the noise, open a window and try to figure out what is going on. The tapping or clicking will increase as you accelerate and become faster. This could be what is known as a 'tappet,' or the upper valve train. The causes could be a number of issues starting with a worn part. It could also indicate that the oil pressure is low. Check your oil pressure gauge when you hear this sound and follow guidelines to determine the exact problem. Take the dip stick out and make sure you have enough oil in there.

2. Deep Knocking Noises

These are usually a sign of deep trouble and yes, you should be worried. 'Rod knocking' sounds could mean that one part deep inside the engine has worn out. If your rod bearings have worn completely out or become too loose, it is only a matter time before the bearings fail. In this case, you should not use the car until the knocking engine noise has been fully and properly tested, diagnosed and repaired.

3. Rattling and Whining Sounds

If you hear a whining or rattling engine noise from your car when you accelerate it could possibly be that your cam shaft belt is badly aligned or slipping. Have your cam shaft belt checked or look it over yourself if you have the right knowledge. It should really be fixed by a good mechanic, otherwise you could have more trouble further down the road.

4. Squealing When Accelerating

This is an unmistakable sound and it is quite ear splitting. This is your fan belt telling you it is in pain. The fan belt can loosen over time and when you start your engine and the fan belt (often called the serpentine belt) can squeal when the rubber teeth underneath it start to drag. If the fan belt is loose it will not be able to move at the same tempo as the pulleys which control it, hence the squealing noise. If this happens with your vehicle you should look in the manual for repair procedures and tighten it correctly. It may have worn enough to need replacing.

5. Grinding Engine Noise

If you hear a deep grinding engine noise, this may not be your engine, but your brakes. Check your front brake pads for signs of complete wear. If the metal is grinding against the cylinders, replace your brakes. If the noise does continue, check with a good mechanic for correct diagnosis.