I have the same problem. I have tried the MAP wack, new MAP sensor, new fuel pump, fuel filter, re-set valves, cleaned the air idle control valve, and seafoam in the brake booster line to clean the intake. Still sputtering/bucking. Gonna try and swap computers n see if that works. Stop and go traffic is a nightmare. Gotta find a fix for this. Experts please help!!!! lol :hello:

I'd check the voltage on your TPS sensor. I believe the service manual says it should be at .4xx volts but mine and my buddies s2ks both run a voltage of .28 when you turn the car to the on position without starting it. I believe it's the middle wire of the three coming out of the back of the TPS that you back probe w/ the positive voltage sensor then ground the negative on the engine or where ever.

If you have a faulty TPS sensor, unfortunately you'll have to buy the whole throttle body assembly, they don't sell the TPS by itself.

^^ **** that I have aftermarket TB

Well I finally got the chance to scan my car, I'm pretty sure its the MAP sensor. It was reading 28 inches of vacuum with the key on engine off lol. and I just put my header and exhaust on, but cant enjoy it cuz my car runs like crap :(

If its reading serious vaccum with the car off im sure thats it

It'll be here 9am tomorrow YAY. I'll post up if it fixes it.

My car started doing the same exact thing today driving from Arizona to NC for the Dragon meet.

Symptoms:

- Low RPM bog in gear (below 2500 RPM). When this happens I see my AF go very lean.

- Slight popping sound from the exhaust in no-load conditions between 3500 and 4500 RPM (when holding the pedal steady)

- When I lift off the pedal while cruising (part throttle) I see my wideband go from the 14.5:1-15:1 range to 12:1 to 13:1 momentarily

- Idle droop (have had some droop since installing the SC - but it is notable worst now)

I stopped in at a dealership in Dallas and picked up a new MAP sensor - did not fix the problem. Checked for vacuum leaks and did not find any.

Only thing I noted was when I monitored the Primary O2 sensor voltage it was a very jagged/choppy sine wave (yes - I am carrying tools and a scan tool with me on the trip). If I remember correctly it was a much cleaner smooth sine wave last time I checked it.

I have confirmed that it is not related to my SC or fuel management - as I removed the belt, disconnected the engine management and tied open the bypass (essentially ran it NA).

I am going to pull the plugs as soon as the car cools down and leave the battery disconnected over night.

Interesting that my car is also a MY02.

If anyone can confirm that the voltage from the Primary O2 is supposed to be a smoother looking sine wave please let me know. If anyone has had this problem and solved it please advise.

I am currently in Jackson, MS and need to drive the rest of the way to the dragon tomorrow. I could probably stop by a Honda dealership on the way for a quick O2 sensor install if it is confirmed that it is the problem.

You can also reach me on my cell - 6 0 2 6 2 5 1 3 4 4

Appreciate any help anyone can provide

Also - I have no CEL

May just pull the plug on the O2 sensor and let it run in open loop.

Pulled the plugs and all looks good - if anything it appears to be running slightly richer than usual.


S|2ocK - how many miles are on your car? I just rolled over 50K

Another option I am looking at is to take the analog output from the AEM wideband and feed it to the ECU.

Can anyone confirm that the Nernst output option (P4) is the correct setting?

https://cimg5.ibsrv.net/gimg/www.s2k...67cb52400d.jpg