Okay, thinking out loud... O2 sensors detect oxygen, when you misfire they see a burst of O2 and go LEAN. The engine is apparently getting richer and richer right? So an O2 is seeing oxygen and the ECU is throwing fuel at the problem - watch the catalytic as this is a fast way to burn it out BTW.

Could an injector wire be swapped cylinder for cylinder? What happens if you accidentally swap O2s? The one that is looking to see a leaner mix after the catalytic instead sees richer... the error code said improbable reading and I'll bet it thinks it's seeing this.. Can you get raw O2 readings? Honestly it might just be easiest to try swapping the O2s and see what occurs. Someone mentioned that the front O2 uses a different number of wires - check that for sure.

As for the flywheel... the timing is off the outer edge I believe. The dual mass is a sprung inner hub if it's anything like the Supra. Resurfacing that could screw up the springs and things if done wrong on the Supra, probably this car too if grinding fluid gets in there. It was also possible for the mass in the middle to move too easily when a replacement was needed, springs go out. NEITHER of these things would have ANY effect on the outer ring. Think about it - if the sensing was done on a piece that could MOVE when the engine was turning you'd never be sure of an accurate sensor reading - especially with the millisecond response time of those kinds of sensors. That your mechanic, who has SEEN the flywheel thought this could be a possibility concerns me. Especially if he thinks it's a common issue on these cars? I could be wrong but I'm pretty sure the ECU isn't sensing off something that can move around for crank position. FWIW my car has a take-off 997 part that had few miles. Apparently this can be retrofitted without issue so when shopping we can consider that - mind you I'm NOT thinking you need a flywheel at this point.

Vivid has a decent pic of the flywheel on their site -> http://www.vividracing.com/catalog/p...6.html?image=0 and this site gives a somewhat decent idea as to how these beasts work ->

 

Thanks for that detailed technical explanation. Helps me understand things better. So in summary you think these codes are not triggered by flywheel issue if there is any?

My car is catless btw...why would the car misfire in the first place?

Also it most likely is due to bad o2 sensors , swapped o2 sensors or a improper install of injectors on bank 2.

Please correct my understanding if wrong. In my opinion , codes indicate a mechanical failure and this is not tune related as stated by the shop.

 

They changed the o2 sensors and the p0040 code went away , but now its misfiring on both banks Cylinder 1,3,6 with black smoke coming from the exhaust.

Anyone have these mutiple and random misfires?

 

Well your choices are:
♦ Fault in ignition system
♦ Fault in injection system
♦ Flat-base tappets (valve lift fault)
♦ Mixture too rich
♦ Mixture too lean
♦ Mechanical causes: valve lifter chatter, camshaft control times adjusted, variocam

check for leaks, plugs, coil packs connections, fuel pressure.

Are you using PIWIS to help diagnose?

 

We checked the injectors , o2 sensors etc. The mechanic thinks the tune is too rich causing these issues. EPL thinks the tune is not the issue , its a mechanical fault.

I am going to take the car over to AMS and get this resolved. EPL's authorized shop in chicago is AMS.

 

Ultimately you are going to have to just start ruling out issues...I would start with leak test as leaks cause all kinds of strange issues...then I would look at connections, plugs and coil packs...then look at fuel issues...pump and pressure...of course you could also flash back to stock just to rule out the tune...GL!

 

Vinod,

Its been misfiring on bank 2 long enough to cause problem else where. Once you find the root cause, you will likely have to do plugs.

This issue originated on only 3 cylinders, one only 1 bank, after an injector install... That should give you a fairly clear road to head down during diagnosis.

 

Sounds like a faulty injector? Stuck open and dumping fuel? Unplug 1 injector at a time and run it?

 

Possible, however the 996tt DME is VERY good at picking up single cylinder misfires.

It looks like this issue is global to bank 2.

 

The car is now in good hands at AMS (EPL authorized shop in Chicago).

 

Thanks to AMS and Tony at EPL. The issue was swapped /bad o2 sensors which caused the car to run rich and foul the sparkplugs. Btw...the o2 sensors were installed by another shop in Chicago, AMS sorted out the mess created by this shop. PM me for the shop info so you can stay away from them.

AMS and Tony identified the issue and got new plugs installed and the problems went away. The car runs great ...so the stock flywheel is not an issue.

 

Great glad to hear you are up and rolling again!

 

Figured they were swapped but it never came to my mind they could be bad. Glad you got it worked out, Now go enjoy her!

 

... Im glad it was an easy fix.

 

Good to see it's fixed. Nothing worse than breaking something that works and then having to chase the fix.

How fast is it?