I first thought it was a S5 TII, because of the knockhole sensor or w/e. I was told that it was a S4 by someone else, because the engine doesn't have an electronic OMP. It does, however, have square purple injectors. I am convinced it is a S4 but I was just wanting to know your thoughts. (Also... was the S4 TII tranny bigger than the S4 N/A tranny?)

 

An easy way to check is if there is a filler neck cap on top of the water pump then its an S4. If it only has one filler cap and it's on top of the rad. then it's an S5.
I attached a pic of an S4.

 

Hmm... Alright, thanks a lot.

 

do you have any pics? that's the best way of verifying which series.

 

... An EOMP is S5, knock sensors above the plugs is S5. The wire harness conectors are higher quality on the S5. theTPS is a double plunger on a S5. The intake manifold is a little differnt on the S5. The turbo exhaust manifold is shorter on the S5. sounds like it could be a bastard rebuild that may be using parts from all different engines, not a bad thing. Just makes it difficult to identify

 

the block itself can come from anywhere. because of the nature of our cars, people like ot mix and match different things to make things work. does it matter?

 

how many blades does the clutch fan have? 8 blades is S4, 10 is S5. Metal coolant filler neck (the tube that the cap is attached to in the above pic) on S4, plastic on S5. IIRC, S4's had the EGR passages thru the rear housing, S5's didnt. S5 transmission has more ribbing on the outside, and slightly different plugs. You already got the injectors and the knock sensor, altho it may be using a different harness... i know the engine in mine is now a bastardization, completely possible in your case as well.