Installed new distributor need help

[yruyur]

I installed a new distributor in my 88 Suburban (5.7). I followed the installation procedure (TDC, point roter to #1, etc.) I timed it (I think it's adavnced about 10-12 degrees) and generally speaking, it runs great. However, during cold starts (overnight or several hours) it snorts and jumps and backfires until it warms up a bit and then everything runs smooth. I replaced the coolant sensor and checked for vacum leaks, etc. Everything appears OK. It all started when I replaced the distributor. What the heck did I do wrong? Would being one or two teeth off with the distributor be a problem if it times OK? Help please.

[amac209]

did you unplug the timing advance connector when you set the timing if not it's probably over advancing

[yruyur]

Originally Posted by amac209

did you unplug the timing advance connector when you set the timing if not it's probably over advancing

No I didn't. Where is that located? So I unplug the advance connector, time as usual and then plug it back in?

[amac209]

it's single wire connector i think it's by the left side of the firewall. follow the distributer wires and you should be able to find it.

[TEXAS-HOTROD]

I think it is a tan/black wire inside, just under the heater box, above where the passanger's feet go (I coild be wrong). Should be set at 0 deg.