Avensis 2001 Vvti Manual Pre Detonation/pinging

[waqar_lionheart]

Hi All,

Sorry to disturb, but i think i might have a pinging/pre detonation issue on my car. It only happens when engine is warm(it runs amazing when cold with good economy) and only when i press the accelerator gently. If i press it significantly, it disappears. I have had the car for a year nearly now and when i bought it, the check engine light was on. It had both pre cat O2 sensors out. I was told its evident from history of the car(it came with full toyota history) that these had been out for the last 6/7 years. I have now replaced them and the light has disappeared. I also have a haynes manual and try to carry out most repairs myself. In the manual it is said that IF THERE IS A TIMING ISSUE, i.e. crankshaft position sensor, camshaft position sensor or knock sensor, these are zero tolerance sensors and a FAULT WILL BE REGISTERED. I have no fault but fear that some how its knocking and potentially kill my engine. Any help would be greatly appreciated.

Best Regards,

Waqar

[Konrad C]

Your car is running lean on light throttle openings.

I find it hard to believe that the car could be driven and pass MOTs for 6/7 years with faulty pre cat sensors! If you like me, have all the MOT certificates, did they come with the emission test readouts?

Maybe you should an additive to clean the engine and fuel system. The fuel injectors may need a clean - this is where the additive may help.

You should get a code reader or get a diagnostic check for stored codes, if not done so already.

[waqar_lionheart]

Hi Konrad,

Thank you so much for the quick reply. I have a odbII fault code reader which i have used religiously on my car since i got it. These two were the only codes stored on my car. I think from memory i havent got the paper work in front of me but these were p0135 and p0155 bank 1 sensor 1 and bank 2 sensor 1 respectively. I have changed these and the light has been off. You are spot on with running lean on light throttle openings. I will add fuel additive. I have changed the spark plugs and cleaned out air filter(it was pretty clean i just cleaned it some more) and it does not ping all the way up box hill any more but never the less still pings until i press accelerator past the gentle press. Result is bad economy and slight loss of power until it catches up with me.

So now. Can you please advise on how to fix the issue of running lean on light throttle openings.

I really appreciate all the help as I am tight on budget and try to fix most things myself.

Regards,

Waqar

[Konrad C]

Hi Waqar,

I like Boxhill. Will have to visit there soon.

Back on subject, I don't have anymore information other than what I have provided. Just keep adding fuel additives, change petrol supplier, go for a quick blast in a lower gear or get the injectors cleaned. I think partial blocked injectors could be the cause.

Another option that you try another knock sensor, but that is expensive. Just make sure the connections are clean and good with all the sensors.

A few years back I had a Maestro 1600 that pinked badly. After sorting out the carburetor, mixture and a few good long high speed journeys, the pinking had gone.

A good oil service will also help. Your engine is vvti and the oil is vital to the running of the vvti mechanism. Make sure the oil level is good because the pressure affects how the vvti mechanism works. VVTI engines can have issues with oil burning.

Why don't you pull the EFI fuse in the engine bay fuse box, for about a minute so the engine has to relearn the setting. It may help.

Recap. Start cheap - connections to sensors, fuel additive, injectors cleaned, oil level, oil and filter change and reset EFI by pulling fuse then going for a multi route drive so the car relearns setting.

I would hold off changing the knock sensor unless last resort.

[waqar_lionheart]

Thank you so much for another quickly Konrad. I really appreciate the advice given and I shall follow it. I was thinking about the Knock sensor as well but learnt that these have to register a DTC fault code instantly. Anyways since there is nothing here, I shall start with cheap fixes and carry on. This is my little project car. Also i am aware of oil burning issue, thank God there is nothing of the sort here. There was a major oil like from rocker cover/cam cover but that has been fixed and I have kept an eagle eye on it since an oil change 200 miles ago and it seems to hold steadily a whisker above the max mark. I shall try with fuel additives and I am going to germany soon, should help with long blasting on autobahn . If that does not work, I should take the fuse out and cause it relearn. I was wondering though whether running lean without the O2 sensors would cause it to map itself for a lean burn and then relearn once lean mixture O2 sensors were back up.hmmmmm???? perhaps something to think about...

Like i said earlier, many thanks for replying. I shall keep you posted with the progress.

Best Regards,

waqar

[waqar_lionheart]

Sorry to disturb once more Konrad but do you think that this pinging issue would be present when stationary. I am just thinking as you said that it might be running lean on slight throttle opening but surely it should also have a lean spot when I press the accelerator when stationary. Please help as I am quite baffled by this. I drove to mums today on a217 and drive it in higher revs. Obviously the difference isn't apparent yet. We ll see. I ll put in high octane fuel tomorrow on my way to work. Hopefully that ll cure it.

Regards,

Waqar

[Konrad C]

Hello Waqar again

The engine will only ping or pink under load. Just pressing the accelerator whilst stationary will not make it pink, unless the timing is really advanced. What you should not do is drive the car at low revs in a high gear, also known as labouring the engine, as it is not good for the engine.

Basically if you drive the car like a diesel the engine will protest. Drive in a lower gear and use a bit more revs as you said you are doing.

As I said before, if your engine is vvti, the cam adjusts itself the the engine speed. This works using the oil pressure on the vvti mechanism. The oil pressure works with the engine speed. That is why I said make sure your oil level is correct.

I also checked for other cause of pinking and carbon buildup is mentioned. Again additives and a good high speed drive should help clear some of that. Again labouring an engine can cause carbon buildup, plus short trips and continuous town driving also adds to the problem.

I think everything has been covered and unless you are prepare to spend a lot of money, the tips I have told you should help.

Konrad

[waqar_lionheart]

Thank you very much Konrad. I have put in a higher octane fuel in this morning and have been driving it in higher revs. Thanks again. I ll keep you posted of the progress.

Regards,

Waqar

[Konrad C]

Hi Waqar,

I forgot to mention that my car occasionally pinks when pulling from a low engine speed, but it goes away quickly.

The pings are not loud so it does not bother me.

I noticed that you have helped another member with the window washer motor problem. When mine went wrong, I tested the motors by reversing the connections to find the fault. I got a pair motors from the breakers. Good photos.

Konrad

[waqar_lionheart]

Hi Konrad,

Thanks for staying in touch. I have completely forgotten to mention one factor out of all this. It's when I give it the beans, :) very very occasionally, it smells like rotten eggs. Yes I know CAT. But I am pretty sure if it was cat then the smell would be behind me and not in the cabin. It makes me think that there is a leak per cat somewhere and it might be contributing to the problem???? Just wondering that's all.:) cheers for your time earlier.

Regards,

Waqar

[waqar_lionheart]

In the cabin only when I have a driver side window open.

[Konrad C]

Hi Waqar,

That is normal for the rotten eggs smell when giving it the 'beans'. There is a double meaning here! :)

There is nothing wrong with the car.

I have sent a personal mail to you, but will repeat that our cars are nearly the same except for the engines. Mine is a phase 1 Avensis, your car is phase 2. The mechanical difference are the brakes, you have rear discs to my drums.

I will answer most of the queries depending on my experience and knowledge. There are some great gurus on this forum with far superior knowledge.

I hope the pinging reduces over time with the tips given.

Konrad

[waqar_lionheart]

Oh by the way. Just realised that around 2 months ago I changed the spark plugs and got the normal (not irridium) ones. I have to say it was probably a mistake. BUT SINCE YOU SAID THAT YOU ARE A LEAN BURN ENGINE:)(you naturally run hot), can i ask is it a good idea to replace my spark plugs with colder spark plugs (I am just SUGGESTING that spark plugs running hotter also cause pink/pinging). Having said that I have no idea how to tell apart a normal spark plug with a colder one ( i know the idea that colder carries more ceramic bit). an you recommend extra cold spark plugs for my car please.

Regards,

Waqar

[Konrad C]

Waqar that is a good idea, but I have never dabbled with spark plug heat ranges. I tend to stay with the manufactures recommendation unless there is a known issue. I cannot advise you on spark plugs heat ranges.

This afternoon I drove around Surrey after dropping off my camera for repair in Horley. I went to Boxhill and one particular road is very steep. I had to change down twice to maintain speed. The peak torque for my engine is achieved at 3000 rpm, and I know the vvti peak torque is reached at 4000 rpm.

Remember I mentioned carbon build up in the engine, this could enough to raise the compression which can cause pre-ignition. If a car is used a lot for short trips and hardly warms up, driven at low revs and never been on a motorway or fast road, the carbon could have built up. Since you are doing the additives and giving the engine a good workout, any carbon will be cleared after a while. When you go to Germany and come back, the engine may be better for it.

Konrad

[waqar_lionheart]

Thanks Konrad. That's comforting. Yeah the road might have been just past betchworth station. I think it's called pebble hill and leads up to dorking road. Or if you were travelling on top of box hill it would be zigzag road. Both are very fun. 4000rpm torque sounds fun too. I ll report back after Germany in a few weeks

Regards,

Waqar

[Konrad C]

Thanks Konrad. That's comforting. Yeah the road might have been just past betchworth station. I think it's called pebble hill and leads up to dorking road. Or if you were travelling on top of box hill it would be zigzag road. Both are very fun. 4000rpm torque sounds fun too. I ll report back after Germany in a few weeks

Regards,

Waqar

Waqar, It was Pebble Hill, some of the access was blocked to Boxhill. I circled round and stopped at the carpark between Old London Road and A24.

My car performed well and the wheel bearing is nice and silent. Brakes are still bedding in.

MOT this morning then collect repaired camera.

[waqar_lionheart]

I am sure MOT will go fine as well as Camera.

Oh by the way, yesterday I put some premium unleaded (97 octane rating) and also bought the additive. I have added that and hopefully will see a result. I also bought a treatment for engine oil by redex i havent used that yet as the engine needs to be hot for that. I am pretty sure when i had the oil changed last, nearly 3 weeks ago, 10w40 was used which is not recommended due to the piston scoring issue. So i bought the treatment yesterday to allow it sort of make it better. Will see how it goes.

Regards,

Waqar

[Konrad C]

Car passed MOT and the camera is back in action.

I had a thought whilst driving through the Surrey countryside, another sound similar to pinking under load is a leak in the exhaust manifold or gasket. It may start as a slight ticking and could louder if the hole gets larger.

This is a long shot and may not be the problem.

[waqar_lionheart]

Hi Konrad,

Thanks for remembering me in your thoughts:). Hmm. This is although a long shot but may be worth looking into as THE STINK is there at around 3000 rpm. Makes me wonder as its not exactly giving it the beans (works on pebble hill every time i live on the back of ranmore). Hmm I wonder. Oh by the way can i send you a small video. I want to draw attention to exhaust when engine is hot. Its like its got a leak but it hasnt really in the down pipe and under the car. It has to be someewhere in the manifold.However all of this is a very long shot. But worth exploring MAY BE:). I ll keep an eye/ear out.

Thanks again Konrad and also well done for the MOT and camera.

Regards,

Waqar

[waqar_lionheart]

Hi Konrad,

This mught be interesting. I was driving my wife around today to the local shops and something occurred to me so when I got home I popped the Bonnet open and could hear a little whistle like noise coming from throttle biddy area. I sprayed on some wd40 and the car seemed to just smooth out a little may be it was just me. I wonder if this could cause a little mismatch of ratio. While with my ear to the engine I could hear a little knock coming from the driver side of the engine. I wondered whether this was timing chain rattle or what as I have not heard it before I cannot say that this is it.

I wonder whats happening I suppose I might have to wait until the problem gets worse:).

Regards,

Waqar

[Konrad C]

Hi Waqar,

I think you have found a leak with the spray. The problem is to isolate the actual area.

What you need to do is spray a small area at a time until you get the difference, when the engine smooths and the whistle stops. Once you have found the leak, how will it be repaired? It depends on the part that needs to fixed. Hopefully it is a gasket or tightening of a screw.

The engine knock is you heard is very hard to diagnose and I am not familiar with the vvti engine. It better not be the chain and tensioner because they sound expensive to work on. Also the vvti unit is in the same general area on the engine.

This is why the oil service is very important with these engines. If you have the Haynes manual, look at what is involved with dealing with those components!

I would keep an ear on that area for now.

Thank you regarding the MOT. I have a lot of confidence with my car. The emissions are very good and the car is very sound. There are a lot of newer cars that will not reach 15 years. It all depends on how they are looked after and accidents. When I looked in a breakers yard, there were lots of younger cars in there for various reasons.

Back on subject, Waqar find that leak and see if it makes the difference.

Konrad.

[Konrad C]

Hi Konrad,

Thanks for remembering me in your thoughts:). Hmm. This is although a long shot but may be worth looking into as THE STINK is there at around 3000 rpm. Makes me wonder as its not exactly giving it the beans (works on pebble hill every time i live on the back of ranmore). Hmm I wonder. Oh by the way can i send you a small video. I want to draw attention to exhaust when engine is hot. Its like its got a leak but it hasnt really in the down pipe and under the car. It has to be someewhere in the manifold.However all of this is a very long shot. But worth exploring MAY BE:). I ll keep an eye/ear out.

Thanks again Konrad and also well done for the MOT and camera.

Regards,

Waqar

Hi Waqar once again.

The front part of the exhaust when having a slight leak, gives a ticking sound under load. Find it is very difficult and you need a good eye and ear. The manifold or manivertor (because the front cat is located there) may have leaking joints/gaskets. If you hold a piece of paper around the area and see it blow and even see a bit of soot on the paper, then again you found your leak.

Don't get burnt though!

Konrad.

[Konrad C]

Another thought. BG44K fuel system cleaner! Has any one tried it? I have read about it and what it does.

Are there other additives that can be recommended to clean the injectors and remove carbon deposits.

[waqar_lionheart]

Hi Konrad,

I have been doing this business of putting good oil in and using 97 excellium fuel with redex additive and driving in higher revs etc... I am pleased to say that it appears to be making a difference as its definitely pinking/pinging less but I noticed that under high pressure I am loosing a bit of oil. So i popped the bonnet and looked at things and took some pictures. I am very puzzled as I am thinking is this a leaky injector(s)?????? (passenger side 2 injectors) or is it leaking engine oil from here very puzzled. I know i had a large leak from my cam cover gasket but that was fixed over a month ago where my car used to leak oil like a tap around 2 litres/8/900 miles its now under (1000 miles/litre) but still definitely leaking from somewhere I know these cars have oil burning issues (1.8 vvti) but i dont think mine is burning any.I am saying this as there is no smoke of any kind (also i think if it was burning 1 litre per 1000 miles then it would be producing blue smoke). NOW THEN, if it is leaky injector washers or O rings why on earth is there engine oil around it. It seems that everytime i look at it, the puddle just seems to be fresh and dirtly. I dont understand this. HELP............................. please find pictures attached.

Best Regards,

Waqar

[Konrad C]

Hi Waqar, I am not familiar with your engine but generally I think that you still have an oil leak. If you clean the engine it may show up more clearly. Is the liquid oil or petrol? Id it is petrol then the injector seals have gone.

It needs someone to assist you in person to pinpoint the leak. Good as the pictures are it is difficult to determine where the leak is coming from.

The breather pipe in image 1262, check that for sealing or if the pipe is blowing by.

Konrad