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From: Orlando and occasionally Miami and San Diego
S2 UIM on my S1. WHY?
So I took off the intake (and everythings else) to get the motor ready to be pulled and rebuilt.
I had to be able to start it and get it onto the trailer so I put the intake and maf back on. I then saw that there were 4 hoses to be connected back to the accordion tube (which only has room for 3). After looking at all the diagrams on foxed.ca for an 05 RX8, I
figured Ill deal with it after its rebuilt. The mechanic told me that the UIM looks like its an S2 top half. If this is correct, can I just stick a breather filter on it and let it be, or so I need to cap off open ends? Im already in it about $3,000 and didnt expect to have to buy OMP lines as well so If it wont hurt it to use the s2 half, i will continue to. Im going to ask the rebuilder what he thinks, but I feel like Im already bothering him enough and still like to hear other ppls opinion
There isn't a difference that I'm aware of between the S1 and S2 UIM. There is a difference in the attached oil filler neck between early S1, late S1, and a third version for S2's. Hard to tell, but yours appears to be an S1 design.
There should be three lines into the throttle inlet accordion. There is some variation in cars, but I've outlined both below. You can convert an early car to the later configuration, as many Mazda dealers did under a Technical Service Bulletin, though it requires a revised lower oil filler neck (the part that is bolted to the underside of the UIM. If you already have this version, use CONFIGURATION 2 as outlined below.
CONFIGURATION 1 -- Early cars (2003-2005) not serviced under TSB for oil condensation
----------------------------------------------------------------------------------------------------------------------------- 1. Top-forward, 90* nipple
----Tube with yellow marking Destination: Oil Injection vacuum block Routing: Routes down under UIM, behind alternator and across the engine. Feeds into the back of the vacuum block under the primary injectors. Route above the main wiring harness.
----------------------------------------------------------------------------------------------------------------------------- 2. Top-rearward, 90* nipple
----Tube with white marking Destination: LIM, jet tubes for primary intake ports on intermediate housing. Routing: Routes under UIM, behind alternator, coming out between LIM and water neck. Feeds down into the middle of the outboard of LIM.
----------------------------------------------------------------------------------------------------------------------------- 3. Engine-side, 90* nipple
----Tube without marking Destination: Oil filler neck Routing: Direct run to top of filler neck.
----------------------------------------------------------------------------------------------------------------------------- **NOTE: There are two service ports on the outboard side of the Lower Intake Manifold. In early cars, these will be capped off, with no lines connected to them**
CONFIGURATION 2 -- Later cars (2006+) and early cars (2003-2005) serviced under TSB for oil condensation
----------------------------------------------------------------------------------------------------------------------------- 1. Top-forward, 90* nipple
----Tube with yellow marking Destination: Oil Injection vacuum bus Routing: Routes down under UIM, behind alternator and across the engine. Feeds into the back of the vacuum block under the primary injectors. Route above the main wiring harness.
----------------------------------------------------------------------------------------------------------------------------- 2. Top-rearward, 90* nipple
----Tube with white marking Destination: LIM, jet tubes for primary intake ports on intermediate housing. Routing: Routes under UIM, behind alternator, coming out between LIM and water neck. Feeds down into the middle of the outboard of LIM.
----------------------------------------------------------------------------------------------------------------------------- 3. Engine-side, 90* nipple
----Tube without marking Destination: Lower oil fill neck Routing: Routes under UIM, connecting into the base of the lower Oil Neck.
----------------------------------------------------------------------------------------------------------------------------- 4. Oil Niller Neck
----Tube with white marking Destination: LIM, service ports. Routing: Routes behind alternator, coming out between LIM and water neck. Feeds down into the outboard of LIM via a Y-pipe.
----------------------------------------------------------------------------------------------------------------------------- **NOTE: There will be a set of two tubes feeding into a plastic Y fitting from the LIM service ports. The single return tube from the fitting will route up to the Oil Filler Neck**
