I own a 1989 240 Station Wagon, manual 5 speed (actual 5 speed, not electronic overdrive)

Today I got in the car to head home from a roadtrip. Car started okay, but the orange "shift up" arrow was blinking once per second. As I gained speed, car was running a slight bit rough, and I noticed black exhaust out the back. Got onto the freeway, and car was not quite right. Acceleration not as peppy as usual. And that black smoke.

Before I left I filled the tank. Strangley enough, I noticed that after 15 miles or so, the needle had dropped substantially. Then the engine started to bog, and the only way I could get any sort of power was to let off the gas and tap the pedal slightly. When I would push all the way down, no pick-up at all. I pulled off to the shoulder and when I came to a stop, the engine actually idled quite nicely.

I stopped the engine to look under the hood to perhaps see if there was an obvious wire off the mass airflow sensor, but nothing. It started up rather easily, and that seemed to be the ticket to get the "power" back. I had to pull over 2 more times and stop and start to "regain power", before I got off the interstate and limp home on sideroads. On the regular city streets, the power was pretty consistent. But the black smoke was still there.

Concluding points:

1) I burned half a tank of gas to get from Gettysburg to the DC Beltway (about 60 miles)

2) Orange arrow blinked once per second consistently the entire time through.

3) I installed a new good ECU (a 951) a few months ago

4) I ran a diagnostic check and got 1-1-1.

5) I don't know if this counts for anything, but last night I recharged my AC, and it was quite an ordeal twisting my hands past all the wires by the mass airflow sensor to attach the hose. Once when I removed a spent can of R-134, a bit got sucked into the intake and the engine shuddered for a second. Could sucking up a bit of excess 134-A screw up the sensor?


Thank you for your help...

Alex
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'73 164E/'76 240SW/80 240SW/89 240SW @315Kmiles!