Ignition timing off.

[oldbeatuptruck]

I have a 95 Sierra. I threw a rod a couple of weeks ago and have since replaced with a reman 350. everything together fired right up and runs pretty good.

The problem, when Use a timing light to set the timing. it says that it is very far off. If I bring the timing to 0 degrees, the truck barely runs it seems that this setting is very far retarded. I can twist the distributor to a sweet spot and the truck runs great. But again, when i use the timing gun it says its very far off. Almost out of view from above.

I have replaced the Dist. cap/Rotor and all new plugs. Cant seem to figure out the problem. Any help would be awesome!

 

[chevy]

check the resister on the coil of the harmonic balancer. I had 1 come off before when I was swamping with my queen

 

[chevy]

also take a look at your muffler it might have some water vapor in it and cause a hell of a ground arching scissor configuration with the coil and vapor coil

 

[Molson02536]

I have a 95 Sierra. I threw a rod a couple of weeks ago and have since replaced with a reman 350. everything together fired right up and runs pretty good.

The problem, when Use a timing light to set the timing. it says that it is very far off. If I bring the timing to 0 degrees, the truck barely runs it seems that this setting is very far retarded. I can twist the distributor to a sweet spot and the truck runs great. But again, when i use the timing gun it says its very far off. Almost out of view from above.

I have replaced the Dist. cap/Rotor and all new plugs. Cant seem to figure out the problem. Any help would be awesome!

To set the timing on a TBI 5.7. You need to run the engine and get it to its operating temperature. Once that's has been done, discontent the ecm bypass wire under the glove box and set your timing to the factory setting at 0".

Once you have set your base timing to 0", connect the bypass timing wire and re-check your timing. The timing should jump to the advance and can go as high as a 15"advance if you have a healthy engine and good fuel.

The ecm will control your timing from reading it gets from the temp, cam, crank, and knock sensor. The more knock your sensor picks up, the less advance the emc will allow the engine to have.

Keep us posted and hope this helps.
Molson02536

 

[oldbeatuptruck]

Timing

Molson,

Thanks for your help. I tried setting the timing as you said. The only problem is that when I reconnect the wire, nothing changes. Should I be reconnecting the wire with the engine still running? Or should I shut it off before reconnecting?

 

[oldbeatuptruck]

Timing

I tried restarting the engine, this did cause the timing to adjust, about 8 degrees it's seems to be running better, but not perfect. It idles good but when I turn the ac on, it gets rough.

 

[Molson02536]

I tried restarting the engine, this did cause the timing to adjust, about 8 degrees it's seems to be running better, but not perfect. It idles good but when I turn the ac on, it gets rough.

Re-check all your vacuum lines and replace any that looks questionable that may be cracked and leaking. There is one behind the throttle body that's common to crack from the heat of the engine and its the one for your fuel pressure regulator.

A good throttle body cleaning with throttle body cleaner will also help your issue, make sure you clean out the IAC passage way and giving your engine a seafoam treatment also wouldn't hurt lol.

Keep us posted and stay safe
Molson02536

 

[oldbeatuptruck]

Timing.

Thanks again. I am going to try cleaning that puppy up. Also, I have this wire connector. It isn't plugged in to anything. I don't believe it ever was. Do you know what its for?