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Discussion Starter · #1 ·
OK, I've reset (and replaced AOD to TKO) the computer, replaced the TPS (reset at .90v), cleaned the IAB, reset the idle via the Corral tech section after the engine was warmed up, reset the base timing (minus spout) at 12 degrees (then replaced the spout), and checked for vacuum leaks (none found)... cranks great, idles up then settles down OK, runs OK (actually great), but between shifts and when coming to a stop from driving... the idle will just stay around 1,400 rpm... then slowly settle back down to 900rpm after about 3-8 seconds. Even when trying to drive slowly the motor wants to go to 1,400 rpm (mind of its own).

Any other suggestions? Car never had this problem before the tranny, head, cam swap (Heck, what didn't change).

What device on the car can make the throttle stay up, when the spring on the accelator cable has the throttle pulled back?????
 

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Does your car have a VSS and if so is it connected ? Reason I ask is there are a couple of members that are experiencing the same problem but they did not connect the VSS when they converted to mass air.


Bill
 

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HEY F2FAST!
I am having the same problem you are to the T
I am going to hook my VSS up this weekend, I will tell you if it fixed the prob.
 

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Are you running an idle air bypass plate? If so, fiddle with the screws a bit, that should get it down. Your car automatically does that to keep load down on your driveline (through the VSS at your transmission)and only does it when you are moving, then settles down after you stop......if it doesn't, try cleaning your 10 pin connectors at the back of the intake, open and close them about 20 times, then stick some dialectric grease in there. THat should fix it.
 

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Discussion Starter · #8 ·
Paul, idle air bypass place = yes, it is a carry over from when I had the Paxton blower on the car. I did adjust it some yesterday and really, everything appears fine except the hanging idle. I'll try that Sunday when I get back home.

Still, where is the VSS and what is it connected to, and how? Plus, would it hurt to disconnect it, once I find it?

Thanks! Fred
 

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It could be that, or the 10 pins. But my brothers 90 vert has the plate and we haven't had a chance to get the VSS set idle down where it was before the cam, its also stays up near 1500, but as soon as the car stops the idle drops down within a sec or two to the set 900 or so idle. The VSS plugs into your tranny and is what your speedo cable runs through, it has a plug on it and a hole that the speedo cable goes through before going into the tranny. Make sure its connected.
 

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Your Vehicle Speed Sensor is at your tranny as stated. It has plug on it which should be connected to a wire harness. The wire harness runs through the tranny tunnel into the interior of the car. So one end of the wire harness hooks to the actual Vehicle Speed Sensor on the tranny itself, the other end hooks into a harness in the car that goes to the cars computer. It senses the vehicles speed and makes adjustments accordingly. I also believe your cruise will not work if your VSS isn't properly hooked up. best of luck
 
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