Using GT1 to find a leaky injector

[SlickGT1]

Originally Posted by fmugur

I was looking around to find some explanation about the Rough values and here is what I found I can do with GT1.

E46Fanatics - View Single Post - M54B30 ZHP engine swap into 323

I don't get why you need this. It looks like you have one failing injector, on cyl 3. Why not change it, and go from there.

[fmugur]

Do I? This is what I expect though. I was researching the meaning of the inpa 'rough' values.
What about the 6 and 7 cylinders? What does that mean? Do they run too lean?

[SlickGT1]

damnit, i miss typed. Cyl 3 looks bad. cyl 6 is perfect.

[fmugur]

OK, so the higher the number the worse the injector?
What values do you guys get?
Since 6 is perfect should I replace only one or more?

[SlickGT1]

I'll try to run this tonight on my car.

Where do I go exactly in INPA?

[fmugur]

Thanks Slick. Select your DME and you get to read analog and digital values.

[SlickGT1]

This is how my engine roughness looks. This was cool. I was sitting there revving looking at all the graphs. This one goes to zero at any throttle input. Car was idling smooth at this pic.

[fmugur]

Thank Slick. I guess I should try to replace one injector for now. Your numbers seem to be much different than mine.

[SlickGT1]

I guess it's a 4.8 thing. The point is the all equal looking on the graph. It was awsome watching all the different sensors at work while revving.

[upallnight]

Does a leaky injector cause roughness or is that normally a bad spark plug? Lean condition is associated with misfires, and misfire would be associated with roughness. Are you sure it's a leaky injector and not an injector that is clogged and causing a lean misfire condition? Or perhaps a vacuum leak such as a bad intake gasket at intake no.3?