91 RS Camaro 305 TBI

Recently the car has been acting weird when i get to a stop light.

This happens id say about 50% of the time, sometimes it will happen and sometimes it wont.

Heres the video of the surging, hopefully someone can help me identify what the problem is, the car hasnt died while surging even though it feels like it wants to, even the lights dim a little when it surges.( sorry about the ticking was about to turn at the light)

http://www.youtube.com/watch?v=WCA_Z...layer_embedded


Im positive this isn't a vaccum leak, i suspect its the timing? Or does timing not cause this?

I had my timing recently set at a shop, first i had set my timing to 0 and the car ran horrible even though that was the stock spec, so the shop set the timing to a custom setting which im not exactly sure what it was.

Whats the best setting for the timing on a 305 TBI?

I also suspect maybe the EGR? could it be that its bad and can it cause this?


Any info appreciated

Thanks

 

Positive? Tell us why.



Your missing the point on this one.
If zero is stock and there are no extensive mods then it should run like a bat out of hell. Make it run like stock then mod the timing if it needs it.
You need to know what the timing was set to, ask, then check it yourself.

EGR wouldn't cause a surge, most likely to cause a stall, by my experience.

Lastly, the ECM thinks the initial timing is zero, and as long as it doesn't knock it's happy, but due diligence would be to verify timing marks at DTC with a piston stop. If everything is properly aligned then reprogram the chip with the new setting.
Well that's what I would do.

 

Well im positive because every problem that i had with this car in the past i always associated it with a leak.. To the point where i checked every possible hose, replaced about 5 cracked hoses etc. If there is one left il be surprised but i guess another check wont hurt.

I don't have any extensive mods only mod i have performance wise is a homemade cold air intake through the high beams. I guess ill head over to the shop today and see if i can get it re adjusted to 0

 

Did you check the IAC, it may need to be cleaned or even replaced.

 

I had a problem similar to this. I replaced the throttle positioning sensor, and it went away. Mine acted up sometimes when I had the high idle and I moved the shift, it would surge even more (700r4).