I am about to fire this thing up after some intake manifold work and I have a few questions regarding setting idle. In the pic below is it normal for the throttle stop not to be seating? That gap is 1/8 inch. and Is it possible the cable from the cruise control could be doing this?
Before doing the work on the car, it started great but it always had a big hiccup when I gave the throttle a quick pull. If I remember right it seemed like it idled around 800. The plug was still in the throttle body for the idle screw so I don't know if it has ever been messed with.

 

You’re not supposed to use the idle stop screw to adjust idle because the ecu will just try to adjust it anyway. Did you replace your Idle Air Control that screws into the throttle body on the passenger side ? You can clean it but it’s cheap and old , just replace it, $10-20. Clean the throttle body. Adjust the Throttle Position Sensor with a volt meter on top 2 wires , set @ .54-.60. I set my ignition timing first too. When I was done I felt like it was idling lower than I wanted it to, and I tried to adjust the idle with the stop screw to about 800 rpm. When I next started the engine, it idled high, even warm, because the ecu was making its own adjustments. Then I turned the stop screw back until it idled around 6-700 rpm warm . Normally though, the stop won’t be touching the screw because the ecu is setting idle speed.

 

Yes, the throttle should go back against the stop. A too tight cruise cable could prevent it from doing so. The ECU adjusts the idle speed using the IAC valve. It doesn't move the throttle blades.

 

Duc96, yes I replaced the IAC and I was going to adjust timing before anything else. Is that correct? And then set the TPS?
RWDsmoke, if after timing and TPS, maybe I should try adjusting that cruise cable?

 

FIRST find out why the throttle is not closing against the stop. There should be a little slack in both the throttle cable and cruise cable. I would disconnect the throttle and cruise cables and see if it closes. You cannot set the TPS correctly unless the throttle is closed. If you find you do need to adjust the stop there is a specific procedure to follow which you can find by searching this forum or the thirdgen.org camaro forum.

 

Ok, thanks RWD. I think it is the cruise cable, so if after disconnecting both and the throttle touches the stop, I will adjust that cable to where it should be.

 

I also suggest putting a couple of drops of light lubricating oil (like machine oil or 3-in-One) on the throttle plate shaft bearing points. Where those throttle plates / discs are, each side there is a little V-notch you can see carved in the plate. Just put a drop or two on the black axle shaft pivots near there each side and open/close the throttle by hand a few times. This will wick the oil into the bushing / bearing there where the shaft rotates. If I remember correctly this is the car that sat for years? If so, that shaft may be binding or sticking, and this could help.

I would also (while you have those throttle plates open) put a little WD-40 on a rag and wipe down that throttle bore hole top and bottom. Carbon deposits or gunk can build up a ridge there and if you carefully clean that off it may help the throttle plates close more correctly.

Once these are done, remember that Minimum Air idle setting procedure needs to be re-done. Changing the closed rest position of the throttle plates changes the amount of air going into the engine at idle and the IAC will try to compensate for that. You can do that once you get the engine up and running.

 

RWDsmoke, it was the cruise cable that was preventing the throttle from closing on the stop. Both cables have now got a little slack in them
Ajp01, yes this is that Lost Corvette car that sat for 25 years. Earlier I had removed the TB and cleaned it real good. The people who got the car up and running must have done something with it because there was very little carbon buildup then. I went ahead and lubed those points with 3 in 1 oil.

So then...am I ready to time it first and then set idle speed using that idle screw or just set the IAC and then set TPS?

 

Re-read that other post that we replied to a few weeks back as it shows the sequence. Off the top of my memory it's:

Set TPS at .540V, engine off but key to On position
Start engine and set base timing at 6* with ESC connector undone, engine to operating temperature
Perform the minimum air throttle plate adjustment procedure
Set TPS at .540V (again), engine off but key On
Perform the IAC reset procedure

But like I said, re-read that other post where we detailed this more specifically. Good luck.

 

OK, sorry. I had a 3rd shift moment there.

 

https://www.corvetteforum.com/forums...dle-speed.html

 

OK, so now there is another mystery that is preventing me from continuing.
I am ready to set the timing but when I turn the key to start......nothing, no noise at all. I come out later and it does start a couple times but won't stay running.....then back to nothing at all when i turn key to start. When I turn key to start the anti lock light appears.
OH AND MY KEY IS STUCK IN THE IGNITION. It has been this way for a while. Any ideas?

 

First I'd walk away for a bit and get a coffee or something. Then; check your connections at starter, battery, and engine grounds (above/near the oil filter) for good clean tight contacts. Jiggle your key back and forth to ensure that the VATS chip is making good clean contact with the ignition lock contacts. See if that helps and report back. If / when you get the engine running see if rotating your distributor slightly helps to get the engine timing closer to where it will allow the engine to keep running, then set timing with the light.

Don't worry about the anti-lock light yet, that's for another day.

 

I have an ‘86 and I’m having a lot of the same issues.

 

Before you start adjusting stuff , make sure your floor mat isn’t interfering with the gas pedal or linkage.

 

Well ajp01, the grounds looked good, and the starter and battery connections all good. The TPS sensor was not set but other than that I made no changes.
The car started and I set the timing and set the AIC and TPS. It is idling right at 6 00-700.

 

Good work. Because you've had that engine apart, make sure you inspect all areas near the fuel lines, fuel injectors, and regulator to ensure that you have no fuel leaks anywhere while the system is running / pressurized.

 

I did check for any leaks including all the fuel connections and rails and injectors. All good. Checked for any oil leaks around both china wall areas. All good. Checked for any leak around all the power steering pump and lines I replaced. All good.
Checked the heater core for leaks. All good. Now I can get that part of the interior put back togeather.
But, and this one is all my fault for sure. I had the heater hose water shut off valve off and cleaned and painted it and decided to replace the valve in it. So guess where my only leak is.....at that valve. So I am getting another water valve to replace that one and I can finish with the coolant fill.
In the mean time I have done work on the front brakes and I am ready to do the rears starting this weekend.

 

If the key is stuck in the ignition, jiggle the steering wheel and see if it comes out

 

ABD, I tried all the tricks and it still will not turn to the lock position so I can remove the key.