Vortec 454 idling problem

[RawbDidIt]

This might be what you guys are looking for...

http://67-72chevytrucks.com/vboard/showthread.php?t=711356

Sent from my SM-G965U using Tapatalk

 

[JSlezak83]

Funny you mention the distributor. According to the Torque Pro app I'm using it shows it's 21° off. I don't know much about engines but that sounded off to me. I appreciate it.

How the heck do I turn it? Plug wires are all the way up against the upper intake. I'm guessing it doesn't take much counterclockwise rotation to get it to where it needs to be? It's pretty tight as it is.

Sounds like you need to go about 21*

 

[8T7K5]

https://www.holley.com/products/ignition/ignition_boxes/distributorless/parts/601513

This is looking like a good alternative to dealing with this

 

[Mark Gilbert]

Just a heads up if you weren't aware, the vortec engines cannot have the ignition timed using a timing light. You do not actually set "Timing" on them, the PCM does. What you need to check is Cam Offset, or Crank Cam Correlation. To my knowledge the torque app doesn't give you this data without a custom PID. You also need to check this at as close to 2000 rpms as you can.

You didn't mention if you had a 96,97 or a 98,99. Either way I would look into the 0411 swap.

 

[454cid]

https://www.holley.com/products/ignition/ignition_boxes/distributorless/parts/601513

This is looking like a good alternative to dealing with this

Or.... you could just adjust your cam offset for free (or close to it).

 

[454cid]

...You also need to check this at as close to 2000 rpms as you can.

Just over 1000rpm. I used a little flat blade screw driver to wedge between the throttle and throttle stop.

 

[Mark Gilbert]

Just over 1000rpm. I used a little flat blade screw driver to wedge between the throttle and throttle stop.

Your right, I was thinking 2000 but the info I found was actually 1200.

Here is what I used
http://www.gmtruckcentral.com/articles/distributor.html

The big block and small block are similar for this purpose..

 

[8T7K5]

Just over 1000rpm. I used a little flat blade screw driver to wedge between the throttle and throttle stop.

Fortunately for me, the engine is still idling high at about 1100-1200rpm so that part will be taken care of. Still don't know how I'm supposed to turn the distributor given how close the cap/wires are to the plenum. Given the condition of most everything else on this truck, I think it's safe to assume the distributor is in equally terrible condition and needs to be looked at to see if I should replace it all together.

 

[8T7K5]

This is the last information from the Torque Pro app. Obviously the engine wasn't running but it captures the last data minus rpm's etc.

You must be registered for see images attach

 

[Mark Gilbert]

The readings you are getting are just showing you what the PCM is requesting, not the actual timing.

I haven't tried this myself (I have the HPTuners software so I didn't need to) but supposedly you can make Torque read Cam Offset, or whatever the name of the day for it is.

https://www.tahoeyukonforum.com/thr...ard-offset-adjustment-using-torque-app.88572/

I also read somewhere that "Car Gauge Pro" will already have the PID for Cam Offset