Ok, I start by disconnecting the EST wire. Then use the timing light to get the right timing. I've done it a thousand times, but at what RPM do you set the timing. My car has no emission sticker with instructions. So I am not sure what RPM?

I can't get the car down to the 450 rpm without the engine surging.

I just replaced my distributor, cap, rotor, plugs, and wires. Also installed a ported plenum. I have adjusted the timing at around 700 rpm. I have it 10* advanced. Then I move to setting the IAC, then to the TPS. I am having problems with a stable idle to set thing up properly. I have removed the gas purge canistor, and all the vacuum lines associated with it. I have the vacuum line that runs to this stuff plugged. I guess I should mention, I have a new delco TB. I am using the egr, and have checked all my vacuum lines, and all is well. I'm starting to suspect the IAC motor. Perhaps I should unhook it when the car is surging, and see what happens...

I'm mainly having problems with stablizing the idle. If I could get that to work out. The rest would be no problem. This is the same problem I had before the new TB, and all the other work, and parts, I mentioned above. Any help or observations would be appreciated. Thanks...

 

common sense to me indicates you set the idle at about 700, then reset base timing.

just too many changes all at the same time.

 

Steel: Way to many changes to break it down: I'd go back to 6* BTDC, reset IAC, TPS to stock, check plug wires, and vacume lines... I've never worried about RPM's when setting the timing, just set it then reconnect the EST.
The FSM Bull says 450-550 and it will stumble and die, thats okay, then follow the rest of the settings...I would not go 10* but stock 6*...
I have a great Tech tips on setting all, a group from all the guys put together to break it down...worked great for me... Email me and i'll send if you'd like.

 

6* BTDC is all you'll need. You could even go with 8*...but the factory setting is 6*. I like my RPMs to be at about 850-900 on idle.

 

What are your mods and are you running the stock chip?

 

Thanks for the information. I do not have any mods that are really worth listing. I'll try the 6* btdc. I've noticed alot of folks on here, having that idle surge problem.

I have to go get some blood work done today, but I will be back at it, and see what I can come up with. I know it threw me a code 42, and I believe it was either a code 32, or 36, I can't remember. I've got to obtain a laptop, and get hooked up. I actually had things set up pretty good. I had a stable 800 RPM idle after I set everything the first time. I just had a notion that was to hi. I have the 4+3, so perhaps I should have left it there. I'll keep everyone posted...

 

The 450rpm is only for setting the throttle blade screw with the IAC disconnected. From there the ECM will maintain proper idle when the IAC is connected.

This means that base timing is set at around 700-800rpm.

 

Ok, I believe I can get a good steady idle. So guys, What is the general consenses on idle speed for the standard trans? I was hoping to get 600 rpm. This may not be possible however...

 

I left mine at idle around 900-1000. I'd like to adjust it down a bit more though.

When I drive a while and come to a stop though, it sits at 1400. I think this has something to do with my IAC, though I am not sure.

 

The consensus is whatever is burned into your prom. Using proper methods, the idle speed is non-user adjustable. Once you make the minimum air adjustment, the ECM and IAC take care of the idle speed, unassisted. The only proper way to alter the idle speed is by reprogramming the chip.

 

Steel Breeze,

Normal warm idle for an 88 4+3 car is 700 rpm.

Desired Idle Speed vs Coolant Temp.

Deg C RPM
-40 1200.0
-28 1200.0
-16 1200.0
-4 1200.0
8 1200.0
20 850.0
32 800.0
44 800.0
56 700.0
68 700.0
80 700.0
92 700.0
104 700.0
116 700.0
128 700.0
140 700.0
152 700.0

 

AH, I see, I hadn't even considered that. I guess old ways die hard. Thankyou...

 

Thankyou Pat, That is more help to me than you might know. I still love this forum...

 

Ok, she's idling smoothly now at 700 rpm as per specs. It keeps throwing me a code 36. So tomorrow, I will troubleshoot the burnoff system. I also need to check voltage at TPS at WOT.

Then it's on to Replacing all the U-joints in the half shafts, there bad!

 

A country boy can do it, good luck, replacing u joints is fun and just need little patience. Good luck. sami

 

I got a digital tachometer that displays RPM, pretty slick. You can't really tell with slash marks on the console. Mine looks like its idling at 950 RPM, when it's actually 720 RPM. I'm running it at 10* BDC, seems to elminate a knock that would occur at 6* to 8*.

 

Well Sami, I am going to give it a shot. I copied the write up from a forum member. Like you said, "patience". Thanks...
I noticed that when I was adjusting the Idle. The engine sounded to me like it was idling lower than what the tach said. I need to get a laptop, and start monitoring everything... I am running 10*btdc as well, and it runs real good...

 

Tom here is nice written by scorp on how to replace u joints :
http://temp.corvetteforum.net/c4/vader86/