94 z28 383 pretty much stock

Last night would be the second time that my throttle went crazy on me during a race. How embarassing! LOL When I punch it hard and hit about 4500 in 1st the RPMs just keep climbing. I have to turn the car off to keep from damaging my engine. It's never done it on a gradual high acceleration just when I really stomp.

First is there anything in the PCM settings that can cause this? I ask this cause of the way it just sort of keeps accelerating. Programming has been adjusted but not too far from stock.

Second is it just simply a bad cable getting stuck? If so does anybody have a procedure to diagnose and fix a sticky cable? I can think of all kinds of things since I have some hillbilly in my gene pool, but I would rather do it right.

Quick question regarding cables. There are two that go to the accelerator; we shall call them top and bottom. Which is the cable that goes to the pedal and what the heck is the other one for? Cruise control maybe?

I'll try to keep my foot off the floor until I hear from somebody.

Big Wil

 

Have you cleaned the throttle body or the TPS?? Inspected them? Its a guess im not the greatest at this. I just know throttle position sensor deals with the electronics of throttle. And well if the throttle plate sticks or something maybe??

 

"383 pretty much stock?" Uhhh....

Check the throttle return spring. Sounds like something mechanical is binding either in the throttle body or throttle cable. Should be easy enough to check.

 

Check to see if there is anything that the cable or metal that it controls can get stuck on. Just put it through the full throttle motion by hand under the hood. This has happened to me a couple of times in my Maxima (granted its definitely not the same thing) when i had to take the intake tube off. I couldn't tell something was there until I went past a certain point with the pedal.

 

Sound like good things to check and I'll definitely do so. Thanks.

Regarding TPS is there anything in the PCM in regards to TPS vs RPM that could do something like that?

Well the guy I bought it from gave me a really major song and dance. I'm still figuring out what is or isn't stock and so far it all is. Though if you asked Mr. Song and Dance everything is high end performance. LOL All of his BS aside though I still love the car. We just have a lot to learn about eachother still.

Big Wil

 

It can't "stick at WOT" unless the throttle is wide open.... and the PCM can not control the throttle in any way. Something has to be holding it open.

I have a non-stock rubber inlet connector and clamps on the throttle body, and once one of the clamps was rotated into a position where the projecting screw caught the edge of the cable quadrant, and prevented the throttle from closing.

The extra cable either comes from the cruise control box, or from the traction control box. The one that connects to the pedal is the one that wraps around the quadrant, in the groove.

 

WD/40 the hell out of your throttle linkage and return spring, used to happen to me in my 91, its a lot of fun when its icy and the throttle sticks

 

I would be leery to believe that it is in fact a 383 vs. a 350. Did you get any receipts or verification of the build?

 

Nope. So what can I check to verify the 383 specs?

 

did he have receipts and prove the work was done to the engine? machine shop receipts, parts receipts?