power-drop gremlin

[chuck baader]

Limp home mode? Chuck

[JeffYoung]

That sounds like a ground issue to me. I'd check yours and just add a bunch. They don't hurt.

[Chip42]

Limp home mode? Chuck

most definately - but why??

I'm headed out to CFRC again wed with the S300 dataloging ECU from our FP car to see if I can identify anything.

I'll add a few grounds too. Thanks - see you at Savannah (don't pass me on the outside unless I get this fixed!!)

[chuck baader]

Something is out of spec. Maybe the O2 sensor...is the ECU looking for a narrow band and the OBD2 system use a wide band? Something as simple as that? Chuck

[Duc]

Sounds like it is going into a CAT protect mode. That is it starts leaning the fuel back at WOT to avoid burning the CAT out. Quite common practice, and another reason to do standalone.

You got my phone number? If not get it from David. I think I could get you some time at the office.

[Chip42]

Thanks Derek. - I appreciate the offer to maybe use "the office."
Thinking about the problem a bit more - looking for previous experiences that are similar, the best parallel I have is in my first MR2 - the TPS wiring fell off of the sensor and hanged low and to the rear of the engine room. I was young and it ran fine so I hadn't noticed. once driving in the rain the car slowed and spurted only to 3-4k then dropped to something ~1k and allowed itself to rev to 3-4k again. horribly rough while doing so. suddenly cleared up after a short idle rest. the 2 systems couldn't be much more different, and all of my sensors are attacked, acting as described in the troubleshooting guides of the FSM, and have been dry.

do 92-95 hondas have this cat-protect mode? from what I understand they run open-loop over ~4k at >50% or so throttle. - I checked the PNs for the O2 and the ECU-era (OBD1 - single O2) unit matches the car-era (OBD2) downstream piece, while the OBD2 upstream (the one we are using) is a separate number. worth looking into?

[quadzjr]

Since we are using the "downstream" O2 sensor as an "upstream" O2 sensor I guess there could be a problem there, but wha tis the difference? However I still don't see why it would be intermitent. I hope we learn alot from the logged data. This is getting annoying. It would be nice to have two strong running cars at savanna.

[Duc]

Re-reading this, it looks like limp mode for a lost sensor. Are you sure it is not throwing a code even though the light is off?