Idle issue?

[Shimmyshake]

Originally Posted by sho220

I think what has people concerned is that this idle dip may lead to worse things. Mine ('13 FRS MT) does the same thing as the OP's. Idles around 800, occasionally drops to 400-500 (usually with a very slight shudder) and pops back up to 800. That doesn't bother me. What will bother me is if it gets any worse...it won't be a crisis until it starts stalling or throwing a CEL...

Agreed.

[Demandred7]

Originally Posted by Marrk

Can you support this statement with evidence?

TSBs use VINs to establish which cars need the required service.

Manufacturers maintain historical records and query their data based on build date and other criteria. This generates a VIN list for TSB's and recalls and such. They have a master list and they can see if your vehicle is on their list, but, VIN's are not sequential. Typically queries are based off of when cars track through the completion of assembly or entering into assembly.

They do use your VIN because it is unique and it allows them to pull up the build data on your vehicle. Sequential VIN's just don't suggest sequential assembly.

I would not be able to post evidence on a forum. Suffice it to say that I know someone that works at an auto manufacturer and they have been responsible for generating such lists for recalls. They have been very clear to me that it would be unethical for them to provide such information (ie. proof). And, no, they don't build the FR-S. The post was to help point us in the right direction. I too own an FR-S. Thankfully no CEL as of the time of writing and almost 500 km on the odometer. Thank you for your understanding.

[White64Goat]

So, it appears that the FR-S VIN's start with 70. If the VIN's don't run sequentially, then why does the service manual list 6000001 as the first VIN for the BRZ? Not sure what may have changed since I worked for Pontiac, but it would seem very strange (and kind of sensless) to then skip to say 607408 as the second car produced off the line and then 600002...which is what it sounds like is being said. Seems to me like that would make keeping track of cars with problems way more difficult than if they ran sequentially. Just sayin.....Is there some rhyme or reason that they AREN'T sequential? If you had a TSB recall for let's say 2,000 cars, are they going to list all 2,000 serial numbers that are affected if they aren't sequential? Makes no sense. I remember TSB's listing vehicles for recalls as if your VIN falls between xx0001 and xx2000, bring your car to the dealer for examination.

[Z06tofrs]

Originally Posted by Z06tofrs

As soon as I get home from work I will post it.

Build date is 6/12 last four of vin is 6765
Also when my idle dips the car almost stalls and you can feel the car shake. The. It returned to 700-800 idle but the car was still vibrating badly. It's the manual transmission too.

[gwascopter]

looks like toyota needs a recall before someone gets kill again.

[Marrk]

VINs are sequential until someone proves otherwise. Please, let's not drift off into never-never land. Let's stick with what we have, which is VINs and build dates.

A dip in the idle of 800 rpm to 500 rpm when the a/c kicks in does not seem like a problem unless there is shuddering and almost-stalling and cel codes. It may just be a very lean idle design, perhaps in order to achieve EPA goals. I do not know.

sho220 is concerned that the "idle dip may lead to worse things." This is a good reason why we should list milage in each case, so we know where we're at.*

Z06 speaks of almost-stalls and shaking. I would call this is a problem.




*Question: We have reports that, on some cars, Toyota is replacing cam sprockets and sensors, among other things. Can someone explain why these would fail gradually over time rather than fail suddenly? One post said that his car threw a cel at 91 mi. That would be an example of sudden failure. But most report that the idle dip develops after at least 500 mi., which seems more gradual than sudden.

[number1Tango]

Originally Posted by Marrk

*Question: We have reports that, on some cars, Toyota is replacing cam sprockets and sensors, among other things. Can someone explain why these would fail gradually over time rather than fail suddenly? One post said that his car threw a cel at 91 mi. That would be an example of sudden failure. But most report that the idle dip develops after at least 500 mi., which seems more gradual than sudden.

I get my car back from toyota today. my cel came on at 63 miles!
Ill keep you guys posted on how the car runs and details.

[Marrk]

'Tango, when you post up, keep the work order handy. Tell us exactly what they did.


Thanks in advance.

[Z06tofrs]

Anyone having the issue when the cel and trac control light pops on does it ever shut off? It's happened to me three separate times. The next morning the lights aren't on anymore.

[White64Goat]

Z06tofrs--have they ordered parts for your car or did they tell you to keep driving until parts came in? I have a Saturn that used to throw the CEL for the air pump and it would be off the next day too. Computer stores that in its memory.

I know very little about variable valve timing but this engine has chain driven cams and the VVT is controlled by oil pressure from what I've been reading from other posts. Have not read the service manual on this yet. What I can't figure is that if your cams are chain driven, how can you vary their timing with oil pressure? How would your oil pressure change to actuate some kind of VVT? Is this system used in other brands of cars?

If the cam sprockets are the problem (or one of them) you'd like to think they are retrofitting the engines at the engine plant by now.....

[Marrk]

Originally Posted by White64Goat

Z06tofrs--have they ordered parts for your car or did they tell you to keep driving until parts came in? I have a Saturn that used to throw the CEL for the air pump and it would be off the next day too. Computer stores that in its memory.

I know very little about variable valve timing but this engine has chain driven cams and the VVT is controlled by oil pressure from what I've been reading from other posts. Have not read the service manual on this yet. What I can't figure is that if your cams are chain driven, how can you vary their timing with oil pressure? How would your oil pressure change to actuate some kind of VVT? Is this system used in other brands of cars?

If the cam sprockets are the problem (or one of them) you'd like to think they are retrofitting the engines at the engine plant by now.....

I was wondering: If the cam sprockets are the problem, why isn't this a Fail/No-Fail situation, instead of many people experiencing problems only after approx. 800 mi.? What does the problem, for many, develop gradually?

I don't know about VVT either, but my understanding is that it is similar in principle to Honda and Porsche (to name two). My understanding is that the oil pressure actuates the cam lobe change. It does not affect timing directly.

All of which brings me back to: If it's a timing issue, is it the software (ecu map for timing) or a boggy sensor? In which case, they are changing out the other parts just to cover their asses.

I'm speculating. I hope not fruitlessly. Please correct me on the VVT if I have it wrong.

[azburnin]

Originally Posted by Marrk

az, this was a serviceable video and included all the salient info.

As I watched the entire thing, I never saw your RPMs go below 500. With, and even without, the a/c on, this doesn't seem like a crisis to me. However, maybe it is different if you are sitting in the car when it happens. You didn't say anything about shudder, shake or stalling, so I don't know what the problem is. The guys with stalling, engines dying and cel codes — they got problems.

Please, tell me what I am not seeing.

There is significant shudder, and shake when this happens. I took a video today where the idle goes too 400 then back up. I could post that as well i suppose.

This is a brief video of it going just below 500 into 400ish. The acceptable perimeters, Im certain aren't this severe? Forgive me not including audio of how it felt when it dropped down such as the shudder.

-And yes it isn't as significant as others where it goes from 400 up too 1000+
It may not be as severe as my engine stalling, dying, throwing a cel however the car shouldn't be doing this all the same, and this may just be the beginning of what happens before it blows its Cel all over the place. so to speak.

And To the earlier suggestion of inputting the data all into a excel document sound like a good idea to me.

[Z06tofrs]

Originally Posted by White64Goat

Z06tofrs--have they ordered parts for your car or did they tell you to keep driving until parts came in? I have a Saturn that used to throw the CEL for the air pump and it would be off the next day too. Computer stores that in its memory.

I know very little about variable valve timing but this engine has chain driven cams and the VVT is controlled by oil pressure from what I've been reading from other posts. Have not read the service manual on this yet. What I can't figure is that if your cams are chain driven, how can you vary their timing with oil pressure? How would your oil pressure change to actuate some kind of VVT? Is this system used in other brands of cars?

If the cam sprockets are the problem (or one of them) you'd like to think they are retrofitting the engines at the engine plant by now.....

According to the service mechanic he said " the car should be fine and unless the cel starts flashing at you don't worry. We had to order 2 cam position sensors" they didn't say anyone about vvt. Said 5 days till they get in
Has anyone noticed an extreme loss in power when the cel and trac light are on and you have the rough idle.

[Tricky1980]

They are changing out my ECM as well... when/if i ever get my car ill post up exact parts replaced but im kinda in the dark as they arent really telling me much.

Yes high loss of power when cel/slip lights were on.. it was sorta a limp mode that didtn seem to have a rev limiter. but QUITE noticeable i had to drive about 7 miles to dealership on interstate and it was an quite a difference.

my parts were cam sprocket/gears,ecm, oil sending unit(is waht service writer called it but he doesnt seem 100% part smart).

still no eta on parts arrival.