i have an 87
just switched my intake manifold from a s4 n/a manny to a s5 manny. well... it takes a while to finally crank up and usually floods out beore doing so... when finaLLY STARTS THE ENGINE REVS SO HIGH IT DOESNT STOP REVVING.so i have to turn the car off.....what could be wrong? car ran/started good before intake swap....

maybe a vacuum leak? well thanks in advance
jack

 

sounds like it. did you forget your gaskets or something? i hade a rev problem when my throttle body was replaced and the car started without putting all 4 nuts back on it (only 2, then started).
why did you decide to use the s5 manifold? i'm not sure how vdi works, but i think it involves more than swapping manifolds.

 

i have wanted to do this swap for a good year now and finally i got everything together..... if my egr block off plate is not sealing good... would that be the culprit?
i even screwed my idle adjustment screw on the top of the TB all the way down as far as it would go and still my engine is revving to the moon... vdi kicks in on the high rpms to produce more top end on the "more torque-y" s5 engines...

 

and for n e one that has done this swap...... did your primary fuel rail get in the way of the intake sitting properly ?
thanks

 

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