bigturbo

I recently did the tb mod and removed the uim. Since I had it off and a lot of the vacuum lines broke I replaced almost every single one with new lines. I removed the buterfiles from the tb and ported it out a bit on the ic side not the intake manifold side. I replaced the second shaft with a plug(tapped it with 1/8 ndt 27 and used a 1/8 plug) but didnt add any loctite cuase I dont know where to get it. I put everything together and never moved the tps so now when it starts up it sits at 1800 and never goes down even after start up. it used to rev to 1500 on startup but after about 3 mins would go to 700 or so. Now it just sits at 1800 rock solid and drives normally besides that. The only other thing I could think off is there is a line that comes off the intake manifold and goes to the tb and there is a green ball with an arrow on it. SHould that arrow flow toward the tb or the intake manifold nipple?? Could that cause this problem. It pulls really hard too but does anyone have a suggestion of something it might be?? Thanks

felixwankel88

my fc did somthing simular to this... i would check for vac leaks

Aaron Cake

iTrader: (1)

Cold start cam? Generally, a stuck cold start results in a 1500 RPM idle, could easily do 1800 combined with a vacuum leak or two. If you remove the water feed to the throttle body, but didn't remove the cold start stuff, then that's your problem.

bigturbo

The coolant still rins through it and I swear i checked all the vacuum lines twice. The only thign I removed where the shaft for the 2nd set of throttle plates and the soleniod that controlled it that had a vacuum line going across the throttle body and connected to the tb with a nipple that I capped off. Those were the only things that removed. Should I have just removed the plates and put the shaft back in with that vacuum controlled solenoid?? or should I remove all the cold start stuff now?? A few people told me I didnt need to remove that stuff to removed the 2nd set of throttle plates and shaft. is that not right? im confused now.

Aaron Cake

iTrader: (1)

If that's all you did, then perhaps something got jammed up in the process? Throttle cable too tight? Cold start cam stuck?

bigturbo

what does the cold start cam look like?? I thought it was the throotle calbe but I loosened it up till there was no more tention on it period and it still sits at 1800. Do you think its possible because I didnt us locktite that there is pressure leaking through the plug and causing this?? I cant think of much else that could cause this problem. BTW thanks aaroncake for the help. You always have helpful info.

ronbros3

What makes a good tune up , inspect everything, check everything, look at everything , at least thats what they taught 50 years ago.

jhammons01

Throttle cable is too tight..bakc it off all the way. then adjust your idle

bigturbo

I did back it off allt he way. its to the loosest point it an be at. I did check everything I could think of at this point. I guess Ill take everything apart and see what happens when i put it back together again. I didnt replaced the uim gasket when I did it soim starting to wonder if that is it.

Aaron Cake

iTrader: (1)

You can find some good images of the cold start system in the Haynes and factory manuals. Located on the back of the throttle body, and kind of hard to explain with text. The cold start holds your throttle plates slightly open to give you that ~1500 RPM cold idle. As coolant warms a wax pellet in the throttle body, the cam moves and closes the throttles.