First of all thanks for all your help so far guys. I REALLY appreciate it. So i got my y-pipe and cat welded so no more open headers but now i have a problem. The car seems to think its a toyota and wants to accelerate by itself. I let off the gas but yet it still idles high and i can hear it idleling high. It seems to not be noticable when the car is actually moving but it is definitely getting gas. I posted a vid but i was driving so it is kinda hard to record and drive at the same time.


UPDATE: Tried to reverse and car flew back so its not just at idle. Also click on the video to play.

 

umm, id like to say thats weird but im not surprised, when I got my car it would idle normal but was slower then dirt, come to find out my cat was gone and set a os sensor bank #3, once i got it fixed, the car would idle at 2k steady. Replaced IAC, MAF, and whoever had the car before used gasket maker for the TBI base and egr valve, i replaced them with REAL gaskets. also cleaned out the choke real good.
Have you tried resetting the system?

 

Concidering what was done I would suspect throttle cable or cruise cable is not allowing the throttle to close. Most likely is the cable routing got messed up.

With a fuel injected car high idle is an indication that air is leaking into the system. There are many things that can cause it. Bad or dirty IAC motor, any type of Vacuum leak and a few other things.

Since you just installed headers my guess is the cable. Since you throttle can not close all the way it becomes a vacuum leak. Test this by disconnecting both the throttle cable and the curise cable and see how the idle is.

 

agree on the cables thats what i was thinking

 

try turning the car to the on position and pressing the gas 5 times to the floor. That should reset your tps (could be an issue)

 

I think it is my routing of the cable, any diagram or pic of how it is suppose to be routed

 

UPDATE: cables are routed fine.im getting codes p0155 o2 sensor bank 2 sensor 1 p0507 idle higher than expected p0174 running lean. this all happened after i got my cat welded

 

Vacuum leak, Did you have to remove the egr Valve? FYI welding could damage the O2 sensor but it is very unlikely and would not cause these issues.

 

Thats what i was thinking next. On closer inspection i noticed my egr to header connection is leaking but i can easily fix that. Now i just got to trace the leak. I thought a vaccum peak would only cause high idle not actuall acceleration in gear, am i wrong? Because the car is definately getting gas.

 

Yes a leak can cause a surge when you put it in gear. Mostly because the computer does not understand what is going on and it is trying to comp for the lean condition. When your vacuum drop (cause you put it in gear) it trys to comp some more only to fail and go into open loop. Rememer the computer control how much gas the motor gets. If you add air to the engine that computer will add the fuel. If you add air to only one cylinder it will try to fix that by adding fuel to all the cylinders. So now you have one cylinder running lean and 5 cylinder running rich until the computer gives up and goes into open loop.