Eta intermitantly running very rich. Terrible MPG. Stalls and sputters

[Wishno87]

So over the last few weeks my eta has been intermittently running very rich. Mostly later in the day. Doesent usually happen when the motor is bone cold.

SYMPTOMS:
1: My MPGs are usually around 27 when cruising in 4th gear around 35-40 but when it is running rich it stays around 15 or so.
2: At idle it tends to hover around 1100 and when i blip the throttle it chokes and stalls for a moment like it doesn't know what to do before the revs come up.
3: Other times at idle it will stay around 500 and run like crap and if i give it any throttle it will just die.
4: Around 3k rpm it will sputter and the tach will flicker like crazy.
5: Smells bad

Temporary remedies.

1: Unplug the ICV and let the idles bounce around a bit. Hasn't been working much lately though.
2: Wait for the motor to be bone cold.

Any input would be greatly appropriated. Thanks guys.

[dashboardmonkey]

i had the same problem on one car, turned out to be the ECU. Swapped in another ECU runs great now

[Wishno87]

I will give that a shot tonight. Thanks

[kronus]

Sticking injectors?

[Wishno87]

Sticking injectors?

That was one of my thoughts. Is that something that could be intermittent.

[jlevie]

I suspect there's more than one problem here. The steps to put the engine right would be:

1) Have a smoke test run on the intake and fix any leaks found.
2) Run the suite of fuel systems tests documented in the Bentley and repair as indicated.
3) If it has 100k or more on it, replace the O2 sensor
4) Verify that the engine is reaching normal temperature and that the DME temp sensor is good
5) If the problems persist, swap in a known good AFM.

[Wishno87]

Already swapped afm and icv. Swapped ecu last night and I haven't had any problems yet but its an intermittent problem so we shall see. Fingers crossed.

[norcalE30]

i have this same problem... switiching to bosch silvers and adjusting the afm seemed to fix it for a while... now seems to be coming back...