Hi, guys,
I have a couple of problems going on with my 1992 245. The main issue is that I'm getting lean and rich codes and it's running like absolute crap. The best way I can describe it is that it chugs constantly while I'm on the accelerator at lower speeds (up until about 55 mph and then it smooths out), and it has about half the power it should. This is pretty much all the time, though when it's really hot outside or it's been idling for a long time, it will run more normal until I put stress on it. Idle is sometimes good, sometimes jerky but I haven't noticed a pattern as for when or why.

Here are some details about the car. It has over 200,000 miles (odometer is broken). Catalytic converter is gone. I've replaced both fuel pumps, fuel filter, fuel pressure regulator, mass airflow sensor, ignition coil, new plugs and wires recently, distributor cap and button, exhaust manifold gasket, and o2 sensor. The exhaust does leak a little around where the cat was, but its not enough to cause this.
I've been chasing this for almost a year and I just can't figure it out.

One thing that happened last week was that I was idling at McDonalds for between 1/2 hr to an hour, and then I left. As I was pulling onto the street, it just died on me, a lot like when the main fuel pump was overheating, the engine just quit. I pushed it off the road and waited 5 minutes and then it started up and ran beautifully. I was hard on the gas on the way home trying to see if it would go back to its normal chug. It did not, so I turned it off, waited an hour or so, and tried again. Still beautiful. The next morning it was good until I got going about 45 mph and then it went back to chugging again.

I'm lost here. Any thoughts?

 

Richness is usually due to air leaks, too much fuel gets injected to catch up: runs rich. Check for unmetered air after the MAFS...

I worry every time I see a long list of repairs since this poses questions of why were they done, what brand parts were used, and who did them (how well)? Throwing "new", usually Chinese parts in your Volvo may not be healthy. You have to make sure all these things are right...

What were you doing idling for an hour at Mcdonalds? This is not healthy for anybody, not to mention being at Mcdonalds...

 

I used Bosch parts when I could, and everything was OEM or closest equivalent. I do know how to swap out parts correctly, so that's not an issue. As far as idling for an hour goes, I know it's not terribly healthy, but it shouldn't affect it that much. Also I had recently drained my battery and I was trying to make sure it had a good deep charge.
Could it be the coolant temp sensor or the ecu? I read that electronics function better in the heat, and it does run better when its hot and i first start it up.

 

at idle, the alternator barely makes enough power to keep the battery charged when most accessories are switched off. to really charge a run down battery, you need to be around 1200-1500 rpm.

 

Good to know. Thanks. Does this mean that idling with most accessories on is actually draining the battery?

 

the headlights are the biggest load, and generally your system is just barely breaking even at idle if everything is working well. you might notice the headlights are a touch yellower at idle than a higher RPM.