My car is definitely lacking power. I know that I have an exhaust leak on the right side (the weld on the EGR flange on my header has a pinhole leak). Since I just picked up datamaster and a cable I was wondering if you can tell if the right side of the engine is running differently than the left, since the exhaust leak is just on the right side. I really have no idea what data to look at. I know an exhaust leak before the o2 sensor causes a rich condition, but I know the o2 voltages aren't going to tell me anything, so what would? I'm gonna get the leak fixed soon, I just want to see how a leak affected the engine in datamaster. I don't have a tune yet either, and as soon as I iron out these last few problems I'm gonna get it email tuned by pcmforless.

 

Compare the long term fuel corrections (block learn multipliers, or BLM's) for Bank 1 (driver's side) and Bank 2 (passenger side). If you have an exhaust leak on the passenger side, the long term fuel corrections on that side will be higher than on the driver's side. That will result in the passenger side running rich. There are 18 different "cells" for storing the long term fuel corrections, so you have to look at a number of the cells to find out if and where the exhaust leak is affecting the A/F ratio.

 

Yah, I just went through my datamaster logs and the passenger side (right hand box correct?) LTerm counts in datamaster are always slightly higher then the left side, usually by about 2-3. Once I fix my exhaust leak, will both sides almost always read the same number? That is assuming the rest of my engine is working fine.

 

Yes... Bank 2 = right side = passenger side = Cyls 2/4/6/8.

A difference of 2 to 3 counts (based on 128) is not too significant. I'd expect something more with a large exhaust leak on one side. Maybe only a small leak.

 

Yes, it is infact a small, safety pin sized hole right on the weld bead of the EGR flange of my passenger side header. I figured it out exactly using a piece of aquarium tubing to listen with. I can hear the leak as well when I am driving up a hill in 6th. I'm going to see if the exhaust shop can fix it while the header is on the engine, hopefully I won't have to take off the whole header off to get it fixed