Could you guys help ? I am a pre 83 E21 320i J-K Jetronic guy and I don't have alot of inherent knowledge diagnosing engine problems with "Da Volavos ja !"

My symptoms are:
1) 19-20 MPG on hiway (really shitty gas mileage)
2) Have to feather the throttle until car warms up. (cold weather - below about 40)
3) Engine surges sporadically sometimes 50-150 RPMs.
4) Engine runs smooth then seems to "bog" down for a millisecond or two while cruising to work.
5) Sometimes dile drops from around 900 (when it decides to idle normally) to about 400 RPMs (in normal-warm engine conditon), I have to feather the throttle to keep the car from stalling.

What has been done so far....
The in tank sender unit was replaced last week
The "main fuel pump" still is a little bit "noisy" (IMHO)

My Guesses (but I need expert help, I hate easter egg hunting for problem)

1)Fuel Press Reg ?
2)Very oddly located vacuum leak ?( I have canvased the engine bay for vaccuum leaks didn't find any !)

Any help from brick specialists would be greatly appreciated !!

Regards,
Rich

Hello I just posted a similar problem, before reading your post. Our probllems sound almost the same except I do not have to "feather" the gas. Could you read the above post (mine) and see if is sounds familiar to you?
thanks
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88 765 w/2stage boost (TO.)

Yeah dude, I just saw it, sounds very much the same. Mine does not cut out and die though, it just "stumbles" and my gas mileage really sucks bad. Cold start is poor too. Do you know where the air-fuel mixture proportioning takes place in Volvos of this year ? I believe it is fuel-air mix related. But, I am not a Volvo expert, I do alot better with the old K Jetronic systems. This issue is driving me nuts !