I'm not very familiar with Speed Density cars. Its my buddies '93 LT1 A4 car. He stated that whenever he gives it moderate to heavy throttle it bogs real bad until he gets to about 3k rpms. He had some codes, read them and changed his O2 sensors out. Was better for about a day and now its bogging again. I thought MAF. However being a '93 its speed density.
MAP?
or Opti?

Ski

 

what were his codes? does he have anymore since its boggin again?

 

he flogged another one...something for the tranny..its and A4 w2.73s btw.

 

if you can get the exact code and we can go from there. this isnt exactly an easy problem to track down lol

 

I had a bad bogg problem, off idle like that and went to the dealer and had them do a top engine cleaner fuel injection service...change the plugs and wires...car runs like brand new. Check the plugs to see if they are runnin lean, the plugs can tell you alot about how the car is running. My no. 1...5...7 cyl were real lean, but after the inj service the car runs perfect. Dont use the stuff you pour in the tank its crap!!!! I also thought my opti was the problem, but I tried this first, saved alot of money.

 

I had a horrible bogging problem. Turned out it was my fuel pump. I also had plugs and wires changed. It made one hell of a difference. I can now spin into 2nd.

 

Did the car have any A/F tuning done after the cam was installed?
Mine bogged real bad down low when before we richened it up.

 

Drive it with the scanner on it and see if when it bogs, the 02s go real low, somewheres around zero. That'll tell you if its fuel related. that being said, if thats the case (upon accel the 02s crash) it could be fuel delivery or programming. a fuel pressure gage will let you know if its getting plenty of delivery, then you just need to figure out the tune. it may need some adjustment in the VE table in that rpm/map range.
something else to consider. That trans is cable controlled (as opposed to electronically controlled). Is it not downshifting when it should be? That would cause a pretty bad bog....

 

I havent talked to him in a couple of days. As soon as I do I will get more info. As said earlier, its a '93 OBD1 car. So, I cant use my scanner to do real time data while he is driving. Plus, he just got the car and is working out all the issues that come up with it. Im pretty sure it needs plugs, wires, coil, new opti, basically a full tune up and some good B12 top end cleaner and injector flush.

Ski