trep

Hola !

Been driving the s2000 (AP1 2002 completely stock, 37k miles) for a week and my only concern so far is the idle. When i got back with it, it was a very hot day and it was driven a lot that day (like, 5-6 hours straight). At night, i gave some gas to engage first gear and the rpm dropped so much that the car stalled. That's the only time it happened so far. The next day, it seemed fine. Was idling at 4 bars, sometimes going to 3. Then, when starting in first adn giving some gas again, would sometimes drop to 2 (seemed to only happens when the throtle was press and released). Tonight is a bit colder here and car was idling at 5 bars (1k rpm) and going down sometimes to 4.

First question would be, what does your idle sits at at a red light for example? Then, what would you consider doing to resolve that little idle thing (can't really call it an issue or problem hehe)? Also, i've noticed that the rpm drops more much when i put it in reverse for wathever reason. I always park the car in reverse and the rpm drops much lower in reverse than in first gear for example, what could be an explanation for this ?

I'm a complete newb in mechanic (i know the basics and read a lot but still).. bear with me

Best regards,

trep

rob-2

Higher idle when the motor is cold and this protects the motor.

You might be stalling because you dont have the map whack. This, if memory services me, resolves this issue on ap1

xviper

Stop blipping the throttle when you're just sitting there. It doesn't like it when it's got hot intake air. Why do you need to give it gas to engage 1st gear? Just put it into 1st. Give it gas when you're ready to move.

trep

I'm not blipping the throttle for no reason. It's just like when you want to travel a short distance (like when you need to pass a speed bumb slowly) and can't engage because the distance is too short. You release the clutch slightly to engage and give a bit of gas at the same time to get going and go back in neutral. Anyway, maybe i should just record it, would be easier to explain.

xviper

OK, I know what you're doing now. You used the wrong term in your first post. You said "engage 1st gear". You are not putting it in 1st gear. It's already in 1st. You are "engaging the clutch". In hot conditions, the car will do that but you must use your clutch delicately so that you don't give it any more gas than necessary. When I'm trying to do that, you can get the car moving and keep it going at very slow speeds at barely over idle rpm. When coming to a stop try to keep the clutch engaged as long as possible (till the rpm is below 1000 rpm).
Also, if your car has some maintenance deficiencies, it will stall easily. Make sure plugs are good and gapped properly, air filter in good shape, fuel is good, fuel injectors clean. Most people don't ever do anything about their injectors. They get gummed up. Clean your Idle Air Control mechanism. It may still drop idle quite low when just chugging along but it shouldn't stall if all the maintenance is taken care of.

trep

I'll look into this. Car was fully inspected before i bought it and things like the air filter were already checked. I know the spark plugs need to be changed. I guess i'll start with this and see what happens ! Thanks for the help !

trep

Well, kindda posting update. Throttle Body was cleaned and it's much better, but still there. Got a video of what it does along with the sound of the vibration. Volume needs to be turn up a lot to hear, sorry for quality :\

http://youtu.be/NuULFdsOHtU

Regards,

trep

xviper

Why are you giving it gas just to put it into gear? That's totally unnecessary. Just put it in gear. Don't give it any gas. If you are having problems going into gear when you don't give it gas, something else needs attention (like your clutch fluid or clutch adjustment). If you don't like that clunk when you put it into first, then put it into 4th initially to stop the tranny from spinning, then no clunk and going into first will be easy and noiseless. So, like I said before, you are increasing the rpm for no reason. You aren't even moving. The speedo stayed at ZERO the whole time, meaning you weren't even getting going.
Your rpm started off too low at the beginning of the video. I think that's because you were messing with the gas before you started the camera. After you blipped the throttle, the rpm went way down and then it recovered to where the idle is normally (900 to 1000 rpm). If you don't give it gas like that for no reason, the ECU will learn to hold the idle rpm at the proper place. Even a properly maintained S2000 in hot weather will have a fluctuating idle rpm if you give it gas like that and don't go anywhere. I don't see anything wrong with your car insofar as the idle situation.
Oh and that "vibration" which shows up on the vid as a kind of flutter after the idle rpm had stabilized, is something else that is likely unrelated to the dipping idle.

trep

Thanks again for your input. What do you think could be that vibration, I can only hear it when the idle dip like this.

xviper

Odd thing is, it only does that "flutter" as the rpm is coming back to normal and stabilizes and even just after it's back up, then it stops. It could be an engine related noise or transmission/clutch related noise. Does it do it if you just do the gas part but not put it into 1st? What about if you do the gas thing but leave the tranny in neutral and leave the clutch alone (up)? To find that out, you may need to do what I just told you not to do just to replicate the problem. Give it gas to make the idle dip and when it flutters, try to trace it under the hood or under the car. You may need someone else to manage the gas or to do the looking and listening.