150000 miles Yaris 2011 poor acceleration and power fluctuations.

[Charlieclangers]

Hi , I purchased a Toyota Yaris 2011after owning it for just over 3 months. It has 99000 on the clock but mytotota paperwork says 15000 🤷🏼*♂️.we only got this after getting documents through from DVLA for vin but that's another story

ISSUE: I started to notice poor acceleration and a fluctuations in power when driving along in the same gear not.moving my foot from the accelerator.

GARAGE OPPION : Having taken it to a Toyota specialist there oppion is it needs a new timing chain. Having looked at my Toyota it said a new one had been fitted in December of 2019.They found no issues with exhaust pressure either which is something we had thought it might have been .

OUR OPPION : having read about it a bit online we've read about vvt solenoids causing similar issues with rpm fluctuation

SALIENT POINT: where in the engine would I find the vvt solenoid and dose anyone have any expiernce with similar issues on high milage Yaris . I get about 30mpg for city driving

Any advice or help would be greatly appreciated thanks in advance

Charlie

[ex-x-fire]

https://www.youtube.com/watch?v=3GgRZS0sRRI here's a video. Do you have any codes? Did you have the maf sensor cleaned?

[Charlieclangers]

https://www.youtube.com/watch?v=3GgRZS0sRRI here's a video. Do you have any codes? Did you have the maf sensor cleaned?

So I had a watch of that video and we have different engine bay layouts I can't see behind the alternator. The only code I have is p0420 which is for an oxygen sensor bank 2. I have also cleaned the MAF sensor using MAF sensor cleaner I'm not sure weather it helped or not due to a bias in my oppion in hopping it would resolve or partial fix the issue

[WeeYari]

Where do you live and what engine do you have? Your location of "My driveway" tells us nothing. If your engine bay layout is different, then you do not have the common 1.5l 1NZ-FE engine most of us are familiar with.

[Charlieclangers]

Where do you live and what engine do you have? Your location of "My driveway" tells us nothing. If your engine bay layout is different, then you do not have the common 1.5l 1NZ-FE engine most of us are familiar with.


I live in London , car was registered in Bromsgrove . It is a 1.33 dual vvti. I believe it is a 1nr Fe engine

Here is an image I found of it ignore the circle https://data.motor-talk.de/data/galleries/0/25/3551/32251426/1nr-fe-yaris-8563614914555935411.jpg


Thanks again

[Kaotic Lazagna]

Don't know anything about that engine, but when was the last time that the spark plugs and coil packs were changed?

Does it only happen at a certain RPM?

I'd also clean or replace the EGR valve.

[ex-x-fire]

In the picture I see 2 solenoids angling into the valve cover just above the oil filler cap.

[Charlieclangers]

Hi, all sorry for taking so long to get back to this post. I have since taken it to an official Toyota dealership. Their conclusion was this " Confirmed carbon buildup causing clogging (On the piston oil drainage holes)" Then they referred to their internal repair codes which are about fitting oversized pistons which are an official Toyota part for high mileage engines. They then went on to say " Due to high mileage it is also likely a new short block would be required estimated cost £4026.71 incl vat " I thought how nice of them to include vat on that price. So I am going to just purchase a used low mileage engine and install that instead, it should cost around £1500 fitted.

Thanks for all your help.

[komichal]

Personally I would not pay that money just to get a new engine with unclear history, with POTENTIALLY low mileage and without guarantee that it will really fix your problem.

[Charlieclangers]

Personally I would not pay that money just to get a new engine with unclear history, with POTENTIALLY low mileage and without guarantee that it will really fix your problem.

Yep that's what I'm going to be doing it is a great car other than its their gear for anything above 20. 4 5 and 6th are but wishful thinking

[kevinj93]

I don't know if the NR series ECU is similar to the NZ series most of us are familiar with but...

On my 2NZ-FE it is possible to find a low throttle situation where rhe ECU can't decide if the throttle needs to be opened or closed. This is probably the point where the pedal starts to show an off idle position to the ECU. I have a stretch of road near my house where I can easily f err t this to happen. The speed limit is 80 km/h, and with a slight down hill slope on the road. If I drive normally, the car will feel like it is surging, and the tacho will show the engine revs rising and falling. If I turn the cruise control on, it runs smoothly with no surging.

[mirageman]

If you are driving along in the same gear and same pedal position and you feel power fluctuations, that tells me you potentially have enough power, as opposed to an engine that needs replacing which would run with low power all the time. Are there times when it feels like you have adequate power? That p420 is a concern. Perhaps your catalytic converter is clogging up? First things first, spark plugs and BG44K fuel injector cleaner. Clean your throttle body too. EGR could do that power fluctuation too, but not sure if you even have one. Variable valve solenoid problems can be a pain when they are sporadic, and you should get a code if it were the solenoid. No code other than the 420 looks like it may just be the second oxygen sensor, but I am still a bit suspicious of the catalytic converter despite the pressure check you mentioned. That could be a big job. There are many things to check before getting an engine. Compression testing is also an easy check for each cylinder, and you'll get to see and/or change the spark plugs while you're at it. A code reader could also tell you if there are any PENDING codes, codes that haven't tripped the computer enough times to make a light on the dash. Could also be a fuel delivery problem, meaning pump and/or filter. Tough to test that on your own too, so I would go the easy route and go with a fuel injector cleaner, my favorite being BG44K, and checking compression and spark plugs. Good luck if you're still dealing with this.

[Charlieclangers]

If you are driving along in the same gear and same pedal position and you feel power fluctuations, that tells me you potentially have enough power, as opposed to an engine that needs replacing which would run with low power all the time. Are there times when it feels like you have adequate power? That p420 is a concern. Perhaps your catalytic converter is clogging up? First things first, spark plugs and BG44K fuel injector cleaner. Clean your throttle body too. EGR could do that power fluctuation too, but not sure if you even have one. Variable valve solenoid problems can be a pain when they are sporadic, and you should get a code if it were the solenoid. No code other than the 420 looks like it may just be the second oxygen sensor, but I am still a bit suspicious of the catalytic converter despite the pressure check you mentioned. That could be a big job. There are many things to check before getting an engine. Compression testing is also an easy check for each cylinder, and you'll get to see and/or change the spark plugs while you're at it. A code reader could also tell you if there are any PENDING codes, codes that haven't tripped the computer enough times to make a light on the dash. Could also be a fuel delivery problem, meaning pump and/or filter. Tough to test that on your own too, so I would go the easy route and go with a fuel injector cleaner, my favorite being BG44K, and checking compression and spark plugs. Good luck if you're still dealing with this.


I have to say well done - You outdid a Toyota main dealer without even seeing the car. When i took the car back to the trade seller i brought it from for them to replace the engine they said they wanted to double-check somethings before removing the engine and they discovered a clogged first stage Cat. So rather than a £600 job it was a £250 job.


Thanks for all the suggestions everyone



MYSTERY SOLVED

[Spellino]

I have to say well done - You outdid a Toyota main dealer without even seeing the car. When i took the car back to the trade seller i brought it from for them to replace the engine they said they wanted to double-check somethings before removing the engine and they discovered a clogged first stage Cat. So rather than a £600 job it was a £250 job.


Thanks for all the suggestions everyone



MYSTERY SOLVED

So what did the dealer do? Replace or clean?

[Charlieclangers]

So what did the dealer do? Replace or clean?

They replaced the cat and still is running fine. Apart from it is almost certainly burning oil but it performs fine for the time being although I will be probably getting rid of it soon. Maybe for something electric?