AlleyCat

I't didnt ping from the factory. You get all kings of afterburning carryover in the ring lands when they are gummed up. You can carbon heads up to death in a couple months of overly conservative driving. Heads run very hot and many have localised steam pockets issues - I had to run the heater in my yaris in the summer to keep it from detuning for knock. Toyota carried a TRD cold thermostat, mainly to help keep Ex. valve stems from overheating and valve seats from distorting, but discontinued it recently IIRC due to smog laws for onroad cars.

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'12 Honda FIT Sport 5M; '11 Forester X 5M;

vintage42

I had a different experience. My 2006 Scion xB has the same engine as your Yaris -- Toyota's 1NZ-FE 1.5 liter four.
http://aatherton06.home.insightbb.co..._xB/Scion.html
For the first few years I drove it conservatively enough to get 34 mpg around town, by shifting below 2,000 rpm and not accelerating hard. It has not had a hot head or steam pockets, as the ScanGauge indicates a steady 184-188℉ when moving, slightly higher in traffic, nor is there any knocking on the recommended 87 octane gas.

Natedog

I understand that you are trying to help, but I know people with multiple degrees and fancy acronyms before and after their names who are quite intelligent and nice people, but I also know several of them who have zero common sense and can't apply their book knowledge to solve everyday problems. I also know people with little to no education who build all kinds of things and can lay out some serious equations on the chalkboard to properly build custom cars, machinery, etc. I don't care what degrees you have or don't...I could list all mine too, but most people probably don't care.

Is it really running closed loop at 185F? Have you looked at the ECU mapping or some other source? If it is running closed loop, it is still not running at peak efficiency at those temps. Rather than cooling the engine, reprogram the fuel/spark curves to ensure zero pinging. All pre-ignition is bad...just because some automotive industry people tell us it's ok does not make it so.

AlleyCat

Agreed, the 1nz engines should be completely knock proof given the small CC area, VVTi _effected EGR, offset crank cL and long stroke. The scan gauge will not show steam pockets, or otherwize localised overheating (unless the sensor is installed right where the pocket is). IME, This ecu will pull timing before knock or even heavy ping so you wont get knock but your scangage should show the timing being pulled. We had a rash of poor gas over the past year since last spring , IDK how your fuel quality is. Not that you asked, but as far as driving below 2000 rpm, I would think driving around the lower torque peak would show the best results for fuel mileage - but this is highly variable on this engine with the VVTi and is, IME, oil viscosity and seemingly somehow filter(!) dependent on the low rpm torque production from this very, very good engine design. I got over 40 mpg average driving hard with that car until fuel quality seemed to permanantly detune the engine. And then the MGP dropped to 34 but the car was run WOT all the time and off almost every stoplight.

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'12 Honda FIT Sport 5M; '11 Forester X 5M;

buckeyetrailfire

Update on my 10 5m ping issue. I have installed a lower heat range spark plug as per my last post. I have used all 3 levels of octane it is much better . With 93 octane it is almost gone. I do notice that with the 93 octane the engine is not a noisey and is smoother running. I have taken it to a different dealer for a second opinion and had the technician take a ride with me and he did agree that is does ping. He did call subaru technical and got no response. I did look for a colder t-stat and only found that there was only 1 # listed. I am gonna try the redline water weter to see if this also helps???

Natedog

Nobody's having this problem anymore?

I've been getting more light throttle ping in my Forester lately. I run mainly 87 Octane gas (as per manual), mentioned this to the Subie dealer at my last oil change, but they forgot to check it. So when I picked up my car the mechanic went for a ride with me and of course it didn't ping when he was there, but....he told me that he just turns up the stereo when his car makes noises....wtf? Where do the dealers hire some of these mechanics?

Lone Ranger

I think they're skilled, its more the system in place at dealer svc dept.'s where each minute of time is money and every job is allocated a specific time to accomplish, and if the mech runs over his time on a job it cuts into his check or something. I'm not sure how all it works but I know they are under pressure to get a car off the lift as soon as practical and get the next job started.

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2009 2.5X, Dark Gray Metallic

Loscaldazar

Each job has a specific time limit attached to it (well 2 actually, one for warranty work and one for regular work). So, an overhaul of a manual transmission is 8.0 hours under warranty, and 11.2 hours under regular work. Thus, if the transmission is being replaced under warrant, the Mechanic only gets payed for 8 hours (and the dealership too). If said replacement take 10 hours, the shop and mechanic have to absorb the 2 "wasted" hours of which the mechanic could have been making money on another project. If it was not under warranty (consumer payed for it), then the shop would get payed an extra 1.2 hours (of which they actually did not work) for finishing it in 10 hours (1.2 hours under the given time limit of 11.2).

It's a double edged sword that cuts both ways, but prevents shops from saying that a transmission overhaul took 36 hours, and you now owe $3,600 (assuming $100/hr labor) in labor, and you still need to add in parts. This means that the warranty company won't pay over $800 for labor at $100/hr, and a consumer won't pay over $1,120 @$100 for labor. They also won't pay under that amount either. However, shops can still overcharge on parts and things like that (or add on hours for a transmission flush, and other small things to give the shop more revenue). Also you can see the reason why many mechanic don't like warranty work-they almost never have enough time to do the repair properly, and why Headgasket repairs under warranty generally don't do so well (they don't remove the engine like they should, because it would take too much time).

There are paragraphs more, but I won't let this get off topic anymore.

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2003 Forester 2.5XS Mod Journal

webfors

Put premium gas in it and the ping goes away typically. I've run only premium in my forester since new. Runs like a champ and never heard a ping.

Old_Lady_Driver

I'm still having the ping problem with my 2008 Impreza, regardless of what octane gas I use. I've given up on a solution; the dealership has consistently refused to acknowledge it as a problem. What I'd really like to know is what's going to happen to my engine as it gets older....surely this is going to eventually damage it, if it hasn't already.

Natedog

$$$ and gas is already through the fawkin roof expensive. I tried 89 octane and it mostly but not always took care of it.

Natedog

Yes, agreed more of a rhetorical question since the whole level of customer service is in the crapper.