CGTBrad

Failed emissions for the first time ever. HC's were around 300ppm (220 limit). Last year was getting a little high but still half the limit. The idle is a little bumpy but steady rpm. I'm confident that the ISV is working properly. My fuel economy seems slightly lower than normal.

Things I have serviced recently.

• New cap rotor and plugs this week (old cap had some carbon deposits on the contacts) cleaned wire contacts
• Oil change less than 250miles ago.
• Cleaned all ground connections and electrical connectors in engine bay.

Troubleshooting I have done:

• Searched for vacuum leaks using propane - found none.
• Cleaned ISV
• While car is running, O2 sensor varies between .3 and .8 volts
• If I disconnect the DPR connection the O2 stabilizes at .6v
• Idle and WOT switches meter good. When I actuate the WOT switch it doesn't seem to do anything
• Coolant temp sender tests good. When I unplug it and or short the electrical connection the engine does not run different.

I haven't been able to pull the codes because I'm guessing my CEL bulb is long gone. Are there test points where I can put an LED setup?

Stuff I have:

• Garage full of tools
• Bentley Manual
• Spare ECU, dizzy, intake from another 87.5, but PN's are different. If I wanted to try the spare ECU or DPR, I would have to swap both.

CGTBrad

Blinked codes 4444 all clear.

CGTBrad

Ignition timing that is.

CGTBrad

It did NOT like the dark grey DPR. Barely ran and was really smokey. Swapped back to the origninal grey DPR. Ran exactly the same with the spare ECU as the original ECU.

mt6127

Does the car start easily when cold and runs ok at throttle but seems to be a bit off at idle? I'm wondering if you have some extra fuel going in via the cold start injector...