Advice on engine idle of used Toyota Auris 2010 (1ZR engine)

[FableBlaze]

Hi,

I was looking at a used Toyota Auris yesterday that I quite liked but there are a few things I noticed that i am not sure about. It was Toyota Auris Linea Sol 1.6 97kW 2010 facelift version with 1ZR engine and manual transmission.

• The idle RPM was not rock solid, there was a slight wobble of the rev-counter needle. Similar to this but about half the amplitude and more constant. I know that rough idle is to be avoided, but the examples I have seen are fluctuations of a hundred or more RPM and some resources claim that silght variation in idle RPM is fine?
• On the first cold start the engine RPM was quite high (over 1.5k if i remember correctly), but it did come down to less than 1k in a few minutes. I am guessing this is normal behaviour of the engine when it's warming up?
• When the engine was warm there was a barely audiable whsteling or whining sound in the engine. I could only hear it barely and only when close to the engine with the hood popped. I am assuming this is just what this engine sounds like but not sure?

Would this be something to stay away from or am i worrying over nothing? Any advice would be appriciated

Just as a side note the Battery was nearly empty at first start. It had enough juice to unlock the car and show the dash lights, but not enough to start the engine.

[Mooly]

If the Battery was that low then I would recommend (once a good or charged Battery is fitted) totally disconnecting the Battery for several minutes in order to reset the ECU. Uneven idle is to be expected whilst the ECU relearns the optimal operating values for the engine and that process may have been triggered by a very low battery condition. The normal idle speed itself can increase and decrease as the air con compressor engages and disengages. 

[furtula]

Variations in idle are because the ECU auto adjusts to compensate for headlights, A/C, power steerings (which is electric), radio, etc.

Try turning all accessories off, and see if it moves, 50 rpm up or down is ok for me, if not, you can do what Mooly said.

High rpm when starting cold is normal, if you remember older cars and using choke, same thing, just automated.

For the whining sound, try turning the A/C off, could be it. Mine also whines a bit, but could be due to mileage (110k miles).

Considering it's a 10 year old car now, i would not worry that much.

[FableBlaze]

Thank you both. I havent bought the car yet as there were a few other things that the seller promised to fix first. But at least i can be more confident about the engine now 🙂

The milage of the one I am looking to get is on the low side I believe (about 67k miles) and probably correct as it has a local history that I was able to check.

The slight whining sound and also the uneven idle was there even with the AC off. AC itself worked and did effect the rpm when turned on/off.

[furtula]

If the whining sound goes up in volume with rpm, could be water pump bearings, so inspect the water pump for any leakage, if possible, but it would be hard to see.

When water gets into bearings, it washes out the grease, and will also start to drip from the weep hole, it's a sure sign the water pump is on it's way out. Another easier to spot sign would be white oxidation on or around the pump itself. Other than that, could be alternator bearings.

If the seller agrees, you can just untighten the belt using the screw on the alternator, and check both of them for any play in bearings, or any weird sound, few minutes work.

[Konrad C]

The ZR Valvematic engine, is a good engine, so long as the oil is changed with good quality stuff. The idle speed depends on a lot of things as mentioned. If the Battery has been changed recently, the ECU will forget it's idle settings. I had this problem after replace the Battery recently. It idled so low that it even stalled. I used a procedure to relearn the idle, once the engine had warmed up. 
The procedure is - warm engine and everything off (heater fan, lights, radio etc.) Press and hold brake pedal, then turn key to IGN - don't start! Wait a few secondsthen turn off. Still pressing the brake pedal and start the engine, letting it idle for 3 to 5 minutes, still pressing the brake pedal. The engine will learn the idle much faster.   
If the water pump is failing, it's an easy fix, having replace my own recently along with a new drive belt.
You may hear the vacuum pump tapping away. That's normal.

Edited July 5, 2020 by Konrad C
Additional info.

[FableBlaze]

Unfortunately the dealer did not get back to me and I found a good deal on a Mazda. But thank you for the replies neverheles 🙂

[Mooly]

Enjoy the Mazda 🙂

If you have doubts over any intended purchase then its probably best to walk away and look elsewhere... you have probably made the right decision walking away from this one. 

 

[mrpj]

15 hours ago, FableBlaze said:

a Mazda

Enjoy.

At least their lamps do stay brighter longer. Older members will remember. Sorry, I'll leave the room!

[Konrad C]

15 hours ago, FableBlaze said:

Unfortunately the dealer did not get back to me and I found a good deal on a Mazda. But thank you for the replies neverheles 🙂

I like Mazda so great decision. I was going to buy a Mazda 2, 5 years back but a friend got it. The controls seem to be very similar.  

2 hours ago, Mooly said:

Enjoy the Mazda 🙂

If you have doubts over any intended purchase then its probably best to walk away and look elsewhere... you have probably made the right decision walking away from this one. 

 

I agree. The seller should make sure the car is running properly at point of sale. With the knowledge I have in regards to the idle issue, if the fix worked (I would do it on a test drive), I would return the car to back with the faulty idle, then knock the seller down a lot! I know that's being cheeky, but that's sellers problem! If the fix didn't work, I would walk away too. As i said before, Toyota's with the Valvematic engine, forgets the idle very quickly if the Battery falls to a very low level, changed or the ECU fuse is pulled for a couple minutes. The 'fix' takes a few minutes and doesn't need miles of driving. But then the car may have other faults, so overall I would walk away and look for something else.  

[David Beavis]

On 7/4/2020 at 2:02 PM, Mooly said:

If the battery was that low then I would recommend (once a good or charged battery is fitted) totally disconnecting the battery for several minutes in order to reset the ECU. Uneven idle is to be expected whilst the ECU relearns the optimal operating values for the engine and that process may have been triggered by a very low battery condition. The normal idle speed itself can increase and decrease as the air con compressor engages and disengages. 

I had a similar issue and resolved by replacing fuse 24 which was lightly corroded.

[Mooly]

That sounds an odd ball problem, you did well finding that one.