Jayboy83

Just been going through the list of possible fixes.....
Just for a reference, my car is supercharged and is using hondata for a remap, cars a 2007 2.0litre with less than 35000 miles on the clock.
I was having an etune done over the net and was close to having it finished when it first started. We'd had no issues at all, the car was running perfect, left for a week. until we came back to it a week later. Then ot had this problem from the word go.
Within that week. Several changes had taken place.
I changed the exhaust manifold to a J's racing. Replaced my greddy back box back to standard exhaust. And installed the latest hondata update on the ecu.
Then the issue came alive. So i decided to go into a garage and use a well trusted, well known and often used, uk professional tuner to take over and sort my issues and get me more power.
The issue was never sorted. My tuner thinks its likely the update from Hondata, he said hed witnessed something similar before, and says that hondata's responses to issues werent great.
This was all a good 6 months ago.
So far hondata have got back to us and said its possibly the o2 sensor, my tuner thinks it isnt likely because everything else is working as it should.
So....as summers arriving, im getting onto this.
So far.....
Ive checked all hoses are connected and not leaking.
Adjusted my throttle cable - (worth doing just for the extra responsiveness)
Cleaned out my throttlebody
Done an ecu reset
Replaced my hondata 4 bar map sensor.

I still currently have the issue, so next up is changing the o2 sensor.
I also want to know where im looking for the throttle position sensor, and any other sensors are that are related to fuelling for a dbw car. All my searchs come up with results for the early models, any pictures and info would be much appreciated on these sensors. I dlike to know where they are, can they be cleaned/maintained and are they easy to replace?.
Thanks again.
Jay

michaelnyden

Tons of s2000s have this and they all seem to have different solutions/problems

zacks2k

I second this. Thank god I'm not crazy. Ok so here is what I've noticed. I put on cat back exhaust, berk test pipe months before and recently moved from Missouri to florida. I visited new Hampshire for a month and ON THE DRIVE to florida I noticed it changed. I did a valve adjustment, seemed fine but now it's back. I'm afraid to even hit vtec now because the SOUND is different, it sounds choppy like a cylinder isn't firing almost and there's NO power up top from what I can tell, without wanting to go up that higH in RPM. The car is sluggish everywhere and lacks power at all times when hot
01 ap1

SuperSaiyan

I have recently felt my car is losing power too at 3rd gear at low rpm. It jerks 3 times then it goes smooth at like 30-50% throttle but its fine if you WOT it. But last year in October my car did this weird thing when it was so hot and i open the ac ( which i think made it even worst ) gave me a CEL P2138 P0219 83-1 61-1 and I was in limp mode. So i reset the battery and it was fine. Then yesterday driving on the highway it was about 89 degrees I open the ac. I could feel my car got really weak like heat soaked and my CEL came on. I didn't have time to drive to get codes and i just reset the battery again. I'm going to have a mechanic check on it next week. Anyone with this experience?

zacks2k

Ok so mine turned out to be bad gas is my only guess because it's pretty much gone. But now like you said I'm getting heat soak and the hesitation is horrible. I used AC too and can tell it makes it worse but I haven't gotten a code from it.

Jayboy83

So.....i finally bit the bullet and replaced my primary o2 sensor. and this has sorted my problem!
The car no longer hesitates or has any lag when coming off and back on the throttle.
Its strange as i never had a cel light come on with the faulty o2 sensor.

Although replacing the sensor has fixed the issue, it has also caused another problem.....i now have a cel code since putting in the new o2 sensor. I pulled the code.
P1157 - air/fuel ratio sensor 1 high voltage.
Ive checked the connections and reset the cel but it keeps coming straight back, i dont understand what the issue with the new o2 sensor is. As it drives better than ever.
Any ideas would be great.

kikkomon

I'm surprised my thread is still going. I said if I fixed the issue I was having I'd let yalls know. I went ahead and bought a flashpro. Installed the Tuned calibration and the issue is gone. Something to do with the stock map was screwed is my guess. I only have a few miles with the flashpro on but I will keep you guys updated. I'm waiting on a call back from inline pro to setup a dyno tune. I'm finally getting shit done on this car. ;-) I did do some data logging, but since i'm a super noob with this flashpro I haven't figured out how to pull my data logs that I did in real time from the laptop. I did some data logginging of the hesitation before I uploaded the tune.

zacks2k

Awesome. Ya keep in touch please. I'd like to see what a pro says if you can figure out how to get them uploaded. I have no idea how to tune at all either. I haven't even bought an AEM or Hondata

shind3

I figured out what is going on. When opening the accelerator (tip-in), the AFR goes way lean. Like 17.5. This is the hesitation that is felt. Tuning the ECU can get some of this out but the logs still aren't perfect with respect to this. What we really need is a way to tune the accel enrichment like you get on any other ECU. I've asked Hondata to add this feature and they have refused to do so because they believe there is something wrong with my throttle body and they would rather have me change the hardware than let me edit the software.




For what I just said to make sense, you need to first understand the reason for accel enrichment in the first place. When manifold pressure goes from a low value to a high value (opening throttle), fuel condenses on the intake manifold walls and you need to temporarily enrich fuel. When you close the throttle, the opposite happens and you need to enlean temporarily to maintain a stable AFR. Most ECUs use a TPS and/or a Load reference to determine how to adjust the calculated injector pulsewidth for the transition.

Read this to fully understand accel enrichment, X-Tau, and wall wetting. http://www.megamanual.com/ms2/xtau.htm

It's clear the stock settings for this are not compatible with my throttle body for whatever reason. I want to tune them. Hondata would rather want me to install a new OEM TB. So, I sit here posting in this thread because this still isn't fixed on my car.

Some things I've tried so far. New OEM O2 sensor. Verified valve lash is set to 9 and 11 thou (Intake/Exhaust). New fuel pressure damper. A couple bottles of injector cleaner.

CarRamrod

There we go. That will definitely cause a hesitation. I have an 08 with 45k on it and it's bone stock. It will do the hesitation every now and then.

So basically they tell you to replace a perfectly good throttle body and try it then. Are there any aftermarket quality pieces to replace the stock one? Wonder if that would help since they SAY it's the throttle body.

I personally think it's ridiculous that you can't tune the accelerator enrichment tables.

I'll subscribe and stay tuned to find out what the issue really is and what the fix is. I'll pull my car away from stock form to fix this. It's a very slight momentary hesitation but it's very irritating.

FWIW mine did it in 32 degree weather so I know it's not heat soak.