shind3

It sounds like they will only take action if there are enough squeaky wheels. Apparently one well documented one isn't enough.

Billman, this has nothing to do with a WOT run, but thanks for your input. I don't always feel a hesitation but I do always datalog a lean spike during the Accel Enrichment phase. Like I said before, it depends on what percent of torque this lean spike takes away. If it's high enough, you'll feel it.

It's really hard to get people to datalog and provide objective data for some reason. I'm an Engineer for a Fortune 100 company and I firmly believe that without data, all you have is an opinion.

Krenath

My 2006 had something I thought was this issue for quite some time. Eventually I happened to notice while playing around with cruise control on a long trip that I could hold down the + button and accelerate smoothly through an RPM range where manually accelerating with the pedal would produce a hesitation no matter how smoothly I tried to apply the throttle.

We checked this out in the shop and, with the intake tube off, noticed that while accelerating with the pedal, the throttle valve would flutter slightly before opening.

After replacing the Accelerator Pedal Position Sensor, the problem went away entirely. Total cost about $250. The car now feels smoother and more powerful as a result of losing the hesitation.

Apparently an area of the resistor inside the sensor got worn or dirty over time and was sending odd resistance values to the computer.

The Prophet.

I feel like in my searches I might have come across one of your posts addressing exactly that, or maybe another with the same exact issue. I've done the same thing too, put the car in cruise in low rpm and try to simulate it that way. I'm wondering though... do you think I'll be able to diagnose that by removing the intake and having somebody watch it as I play with the pedal? Or maybe even get a scan tool that shows throttle opening percentage and see if theres anything funky going on? Now that's really making me think. Especially considering it's a definite part throttle issue.

Thanks for that reply man, I will definitely be looking into that part just in case there's more to my problem than my hunch about the tip in issue.

shind3

That may appear to have similar symptoms to the driver but it is a different Failure Mode and can be verified by datalogs. First of all you can log the APP so as you smoothly press down on the throttle, see if the APP correlates nicely without any jumps. But the fundamental difference between these two is the effect it has on AFR. If the APP is jittery, then the throttle plate will be too; and assuming the ECU's Accel Enrichment is tuned correctly, it will not result in an AFR lean spike since it will know how much to enrich fuel during the sudden increase in throttle when the APP 'catches up' to pedal input.

But in my case, the APP is not jittery and neither is the throttle plate but the AFR does spike lean because its enrichment during throttle transition isn't suitable for the rate of change.

shind3

You don't need to have someone play with the pedal. You can actuate the APP yourself. Just remove two bolts to pop the plastic shroud over it off. Then you can turn the linkage like you would a traditional throttle body. The APP sensor is under the hood in this car as opposed to more orthodox DBW systems.

Or, just datalog it...

The Prophet.

Shind3, I feel stupid.. that's right the box is pretty much a foot away from the tb lol. Thanks for the reminder. I personally don't know many people that have Flashpro and boost but do you think the Accel Enrichment would be a vital tool in tuning if I intend on boosting the car in the future? I have gotten mixed input on that from people I have talked to. All of this is just really making me think.. throttle response is very important to me and I have already started building this as my dedicated track car.

I know I could just get a tune later when I boost and save some money but I could sure use more midrange for autocrossing.. and spirited driving haha. But everybody says Flashpro is worth it just for that and my tuner is giving me one heck of a deal for a full tune.

shind3

Accel Enrichment is most sensitive when the manifold pressure changes quickly. I noticed a lean spike when MAP changed by 10kPa every 100ms which translates to about 100kPA every second. This can happen easily on an NA engine when you open the throttle quickly. I doubt you will run into a situation where boost pressure is increasing by 14.5psi every second. So no, boost will not make this any worse.

Accel Enrichment is used to tune the Throttle Body and Intake Manifold system. A change to either can affect wall wetting phenomenon.

A 2.2L high compression engine should be damn near violent when opening the throttle quickly. But because the AFR drifts lean, torque ramp up is softened. In some cases its softened too much and we feel that as a hesitation. But even at higher rpms and loads where we datalog the AFR shifting lean and don't feel a hesitation necessarily, it is still causing reduced throttle response.

If only Hondata would let us adjust this.

alSpeed2k

Not really sure what you are experiencing. I have an '07 and the only time it bogged was when I first bought it. At low rpm, the car would lag for a bit. Starting out on a hill I was scared I would roll backwards. One of our members came across a thread suggesting we adjust the throttle cable. After removing some play from the throttle cable my car drove significantly better.

cmcd1984

I took care of 90% of the bog on my 06 with a tune and intake.

The Prophet.

Thanks for the input everybody, I really appreciate it!

Although I just started another thread, figured i may ask here too. Do any of you guys' throttle bodies make a high pitched whine? I noticed that mine is loud... While testing throttle plate function with the motor off (car in acc and playing with the throttle cable by pedal position sensor and intake off so i can watch), it will emit a high pitched whine. Right after throttle is shut and i stop messing with it the sound will linger a few seconds then shut off. Is this normal? Never noticed it with the engine running. Motor off, in my quiet garage, its noticeable.

Really trying to diagnose all the little things before my warranty runs out soon.