Steve Wong has given me a new car!
 

Hi All- One more resounding note of happiness and approval for the Steve Wong Chip and his great customer service. ('86 3.2 Coupe- All Stock, no Mods) Steve did a fantastic job of putting up with my inane questions/concerns over several weeks this winter. Steve troubleshot my ECM, and we actually ended up doing a full swap with one of his rebuilt units with the SW Stock Chip.

I finally had the chance to really drive her today- I truly have a new car. Dead solid idle, no flat spots and 1st and 2nd are now a joy- no bucking! While I have no doubt there is a performance gain, for me, it was all about driveability. The Chip has really delivered in that regard!

I say it's the rebuilt DME which fixed the idling and bucking issues with your "old car".

Did you try putting your OEM chip into the new DME ?

Thanks for the kudos! Glad it all worked out. :)

LOTS of people have done this without the DME replacement. They all sound the same, and have the same reaction. They continually revised the stock tune until 89 with the best being the Club Sport.

Stock tune was very conservative.

I doubt it, it was the improved mixture and timing adjustment IMO.

I can make my aftermarket EFI replicate each of these issues.

Perhaps.

But good running 3.2s do not suffer from idling issues or bucking with the stock chip. I understand the increased power/torque from the timing/mixture adjustments. However, the torque curves published by SW exhibit flat spots with or without the chip.

So the direct cause and effect is just not there and the improvements are a secondary effect of the increased performance in my opinion. If your car is idling poorly or bucking, I believe you have other problems with the engine not the chip.

Not questioning the benefits of the chip and the contributions that Steve has made but given this is a technical forum, I'm interested in understanding this too.

Given that I'm dealing with some bucking etc right now I think pmax' point is very well made.

My car runs better with chip than without but neither solved the DME issues -- hence asking if OP had tried stock chip is a good question. Then we would know it was the DME fix that solved the issue with the SW chip benefits being agreed upon but independent of that issue

I agree with pmax's logic. If you use a SW chip to correct idle problems, you must be masking the real issue, since the 911 obviously did not have idle issues when new.
So, is the SW chip just a band aid for whatever is causing the idle issue? In this case, it sounds like it was the DME replacement.