Ignition problem 98 Yukon SOLVED!

[redwing4900]

Problem solved? Cleaned up some chassis grounds that were quite rusty also did one more adjustment to the distributor: it worked the cam position correlation engine light was on until I made the adjustment so that the cap sat against the manifold and it fired up no check engine light. Took it for a ride light stayed away: relief for now. I’ll see what tomorrow brings with this thing. Thank you all for your helpful response/pictures

 

[redwing4900]

I will double check the cmp retard with my neighbor’s scanner. It sounds much better but there is a little hitch when it transitions to lower idle.

 

[redwing4900]

Neighbor is out of town so I had a question about spark advance, and possibly doing it myself with what’s available. This is what my scanner displays spark advance and it’s between 16.5 and 18 degrees At idle (around 725-750 rpm). Do you think it’s possible to time it based on that number or just wait For the neighbor’s scanner? By the way I don’t know what the spark advance should be anyway but I thought this might be possible.

 

[east302]

The base timing isn’t adjustable in that sense. You have to use the scanner to read and set the offset, here’s the procedure from the manual:

 

[exp500]

Redwing-See posts 13,15,24.
Your bluetooth will probably do it.

 

[east302]

CarGauge Pro and DashCommand are two apps that will read the CMP Retard with the extended ($) PIDs. Any OBD Bluetooth adapter should suffice.

Most free apps will probably read the timing, but that isn’t the number that you’re looking for.

 

[redwing4900]

I have a zr 11 scanner from harbor freight. I did some digging within the live data menu and the cam retard info is not there. I could play with it and try to adjust blindly but I’ll do it the right way and wait for the better scanner. Thanks for sending along the procedure. For now I’m just happy it’s running again.

 

[redwing4900]

Today I was finally able to put this problem to bed. Using the scan tool I set cam retard to 0 it was at +10 when the distributor cap bolt was touching the manifold. A few adjustments and the codes went away And final result was 0 Thankfully. I cleaned a couple of chassis grounds that connect to the frame on the passenger side close to the engine, and one of them I attached to another grounding point on the firewall. I think this in the end was the problem because today I had bolted the new ground wire and then attached it with the new segment to the firewall. It had rested against the heater core metal and it caused the same fuse to blow (ENG-I). I taped up the exposed end and secured it to the rubber hose and that problem went away. Just happy that this is over for now, and I also hope that someone else might find this thread helpful. Thanks again for all of your feedback!

 

[exp500]

Good Work!
Please EDIT your post title- Add "SOLVED". Helps people find fixes.