El Camino Central Forum banner

Electronic Timing connector

14K views 16 replies 5 participants last post by  61Airstream 
#1 ·
i'm trying to adjust the timing on my 87 and know I have to disconnect the electronic timing connector. Where do you diconnect it? If it is the plug behind the distributor, how do you get to it? It seems to be right up against the firewall.

Jim
 
#2 ·
it will be a tan wire with a black stripe somewhere between the esc module and the firewall, a single wire plug,disconnect to set base timing, reconnect once you are done,(don't forget to unhook the batt for a few minutes once you have plugged it back in to clear the code)
 
#9 · (Edited)
there is no easy way to explain without pics, but coming out of your distributor there is a four wire plug and a two wire plug(a little late to ask but this is a tbi motor right?)on the four wire plug pin b is a tan/black wire, this is the esc bypass. the connector will be somewhere in this wire between the distributor and pin d5 on your ecm. thanks to gm every vehicle has the timing bypass in a different spot, some are under the glove box, or against the firewall or even right out of the distributor, but it is usually by itself taped to the outside of the loom.

this diagram is for a 1990 g series van, but most of the colors/pinouts are the same
 
#10 ·
there is no easy way to explain without pics, but coming out of your distributor there is a four wire plug and a two wire plug(a little late to ask but this is a tbi motor right?)on the four wire plug pin b is a tan/black wire, this is the esc bypass. the connector will be somewhere in this wire between the distributor and pin d5 on your ecm. thanks to gm every vehicle has the timing bypass in a different spot, some are under the glove box, or against the firewall or even right out of the distributor, but it is usually by itself taped to the outside of the loom.

this diagram is for a 1990 g series van, but most of the colors/pinouts are the same
http://i385.photobucket.com/albums/oo299/skandolis/ELky/wireTBI-1990b.gif
When I plug an OBD 1 scanner in with the motor running, the ECM goes into some other mode. Can I advance the timing when its in this mode without disconnecting anything, or is just wishful thinking?

Jim
 
#15 ·
it is the 4 wire plug at the dist . if yours has a disconnect it will usually be under the glove box or i have seen them laying on the intake harness near the alt. some were a 2 wire disconnect. but the 4 wire plug at the dist will do the same thing.
 
#17 ·
Thank you both, I got in some road repair congestion Sunday night and the temperature on the new motor went up to 210 degrees. I am taking it back to the dealership that installed it next Monday. I am going to let them set the timing...I'll be watching closely. I think retarded timing could be causing both the miss and the overheating. Since it has a 2 yr. 50,000 mile warrenty, I'd like them to see it just the way it is, before I touch it anyway. I took it back to them Friday and they brushed off the miss as carb adjustment. I told them about a 5 degree rise in temperature when I turned on the AC, and they just said that was normal. I just hope this engine's problems in the first 500 miles hasn't hurt it.

Thanks again, I appreciate it and I'm learning a lot about this motor and my EC.

Jim
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top