New engine installed - need TBI timing/idle help

[tj43]

Hey everyone. I just swapped a new ATK TBI 350 into my 88 suburban. Everything went well. Good oil pressure. Temps are good. No leaks. No smoke The engine runs and drives decent. Cruising is great. The only problems are hard starting (lots of racket almost like it’s missing as it tried to start) and sometimes it dies at idle or when shifting into D or R.

I think my issue is timing and TBI idle settings related. I stabbed the distributor pretty close. It initially hunted a lot for idle. I clocked a little advance into the dizzy by hand and it helped some. I couldn’t get a good reading with the timing light.

I’ve read lots of posts regarding the need to disconnect a brown or tan wire before setting timing. However, my truck’s wiring doesn’t appear to match any of the other posts/photos/videos I have found.

I would really appreciate a “101” lesson on how to do a proper TBI/timing initial setup on this new engine. Feel free to talk to me like I know nothing about the OEM TBI on my truck—because that isn’t far from the truth.

Thanks.

 

[dsteelejr]

This is on my ‘88 K5 with a 350. Everything is 100% stock and unmodified. The brown wire is near the bulkhead connector. Hope this helps.

 

[fast 99]

Have seen that connector under the carpet or near firewall inside floor passenger side. If under hood it is separate and usually easy to find. Not sure of the year have also seen it behind the glove box.

 

[gmbellew]

post #2 nailed it with the correct info

 

[Originalthor]

Mine wire was right inside the wire loom oddly enough. I assuming cause it only had 85 km when I got it it was never timed since it left the factory

 

[tj43]

Y’all nailed it. Thanks. Running MUCH better now.

 

[HookChain]

tj43, were you having any hard shifting issues?

 

[tj43]

tj43, were you having any hard shifting issues?

I actually did the very first time I drove it with the new engine. 1-2 was really harsh during the first drive around the block. It had lost a little trans fluid from the converter when we were moving the trans around during the engine swap. I checked the level and topped off the trans fluid after the first drive. It has been shifting smooth ever since.