OK. A while back I replaced my o2 sensor (1988 Max). The ECU was showing a code 33. After replacing I was getting a code 55 - no problems. I'm still getting a code 55 now, but the car runs like crap, but only on a cold start, and only in the first 1 or 2 blocks of driving. The car starts fine and idles fine, but when I attempt to drive off, there is no power and the car does a couple of little bucks almost as if it can't find the right gear and sputters a bit as if it's not getting gas. If I mash the pedal to the floor, I get a bit more get up and go, but nothing like normal. After driving less than a block or so, it all goes away, and the car runs like a champ. Anyone have any idea what this might be?

Thanks.

 

Could be a bad air regulator, possibly a vacuum leak, dirty crank angle sensor, or bad egr valve. I'm having some of the same problems lately.

S

 

Would the crank angle sensor or the egr valve cause the ECU to throw a code?

 

The crank angle sensor would, the EGR, no...
Neither would a vacuum leak...

and if the EGR is out, that equates to a vacuum leak...

good luck tracking it down...

 

Well, by default, the EGR stays closed, but if your like me, I'm in a nasty habit of bending EGR valves! It c ould be that the valve is going bad and isn't closing fully. Very rare though, the EGR valves on these cars are actually pretty solid. So Maxwgn is pretty much correct, vacuum leak. Time to whip out a vacuum gauge, and do some hunting.

S