S4 versus GTS throttle valve
#1
Three Wheelin'
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The throttle body part number is exactly the same but there are differences.
After I changed out the bearings in the TB housing (S4 and GTS have the same part number stamped on the housing I learned that there are some differences to be noted.
The GTS rotating linkage has a cam on it that rotates against a full stop of the TB housing at the same time the TB valve (throttle plate) is in the full open position with the TB valve in a horizontal plane.
The S4 does not have the cam on the linkage the spring stop are in a different location and when the TB vale is turned fully open the throttle valve/plate has past the horizontal plane where the GTS throttle has stopped as can be seen in the pictures
After I changed out the bearings in the TB housing (S4 and GTS have the same part number stamped on the housing I learned that there are some differences to be noted.
The GTS rotating linkage has a cam on it that rotates against a full stop of the TB housing at the same time the TB valve (throttle plate) is in the full open position with the TB valve in a horizontal plane.
The S4 does not have the cam on the linkage the spring stop are in a different location and when the TB vale is turned fully open the throttle valve/plate has past the horizontal plane where the GTS throttle has stopped as can be seen in the pictures
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According to PET the TB part number changed between '93 and '94.
928 110 093 03 --> 06.
928 110 093 03 --> 06.
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No, I think you've sussed-out the difference. The "metal" of the TB is the same, but the linkage is different. I recall that the '94 wot/idle switch has 4 pins rather than 3 and I seem to recall that the fourth pin is used only for auto's to enable a partial-load kick-down. But, don't quote me on that last bit. I'd bet that something about the linkage differences is related to the 4-pin wot/idle switch.
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Casting numbers sometimes aren't even ballpark close to the right part, but with the throttle bodies sometimes you can swap the old linkage to a new same casting number, different part number and model application.
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Another difference I saw on mine was the diameter of the outer throttle opening is larger on GTS TB. It narrows down to the same throttle plate dia., but is larger by a few MM where the boot joins.
And, as noted, the later GTS cars have the 'dynamic kickdown' TPS, which can be identified by having more pins that the previous version (and a connector that's exactly identical to the one that goes to the MAF ... that was a head-scratcher when I went to hook everything back up ;-)
And, as noted, the later GTS cars have the 'dynamic kickdown' TPS, which can be identified by having more pins that the previous version (and a connector that's exactly identical to the one that goes to the MAF ... that was a head-scratcher when I went to hook everything back up ;-)