I noticed it idled more smoothly at the base (5000 feet). I have mine set pretty lean at sea level (using the AFM bypass for idle mix). Maybe at 5000 it was running richer (smoother).

I have not been able to find out any info on the effects of operating above 12000. I still don't know if it died rich/lean, it did NOT forward fire (pop thru the AFM, lean) or backfire (thru the muffler, rich). It would just die like it was getting no fuel at all. Like it was running on the start fuel pump run. I thought the AFM was maybe not turning on the pump. If I had a flat pull off I would have messed with the AFM (pulled the filter to AFM boot and get to  the flap with fingers.

Edited September 23, 20195 yr by Dave WM

I have a fear of heights.  I couldn't watch while you were turning that thing around.  I felt like I  was going over the edge.  :)

On 9/23/2019 at 12:00 AM, Dave WM said:

I noticed it idled more smoothly at the base (5000 feet). I have mine set pretty lean at sea level (using the AFM bypass for idle mix). Maybe at 5000 it was running richer (smoother).

I have not been able to find out any info on the effects of operating above 12000. I still don't know if it died rich/lean, it did NOT forward fire (pop thru the AFM, lean) or backfire (thru the muffler, rich). It would just die like it was getting no fuel at all. Like it was running on the start fuel pump run. I thought the AFM was maybe not turning on the pump. If I had a flat pull off I would have messed with the AFM (pulled the filter to AFM boot and get to  the flap with fingers.

Were you ever able to figure out what went wrong/what you could modify to go higher?

nope, I plan to see if I can add the high alt option and will manually trigger it while watching the color tune plug. I presume it leans it.

On ‎9‎/‎23‎/‎2019 at 5:28 AM, 87mj said:

I have a fear of heights.  I couldn't watch while you were turning that thing around.  I felt like I  was going over the edge.  :)

it was nerve wracking for sure. I am sure the other cars must have thought I was nutz.

Just now, Dave WM said:

nope, I plan to see if I can add the high alt option and will manually trigger it while watching the color tune plug. I presume it leans it.

Zcon will be in Colorado Springs in 2021 - i plan on driving up to try it, maybe you can give it a 2nd shot then haha

2 minutes ago, chaseincats said:

Zcon will be in Colorado Springs in 2021 - i plan on driving up to try it, maybe you can give it a 2nd shot then haha

see if you can get past the Bermuda triangle of pikes peak.

You may want to remove the air filter. I would have tried that but with so many other cars on the road I did not want to try it again. Its not a big deal to turn around (could have just backed down if the engine was completely dead) but I did not want to create another traffic jam.

Just now, Dave WM said:

see if you can get past the Bermuda triangle of pikes peak.

You may want to remove the air filter. I would have tried that but with so many other cars on the road I did not want to try it again. Its not a big deal to turn around (could have just backed down if the engine was completely dead) but I did not want to create another traffic jam.

Is there a way to trick the ECU into going into high-altitude mode?

45 minutes ago, chaseincats said:

Is there a way to trick the ECU into going into high-altitude mode?

IIRC there are pins on the ECU, your wire harness may not be have matching pins so you would need to figure out a work around for that. IIRC its a simple on off switch that connect the pins that activates it. You should be able to find it in the wire diagrams for the harness.

50 minutes ago, Dave WM said:

IIRC there are pins on the ECU, your wire harness may not be have matching pins so you would need to figure out a work around for that. IIRC its a simple on off switch that connect the pins that activates it. You should be able to find it in the wire diagrams for the harness.

I have a california car so I'm guessing its there somewhere haha - I'll check the fsm

 

EDIT: I found it - check and see if you have it, it is this gold pod and the wires going to it are solid blue and solid black.  I'm guessing to engage that we just bridge those 2 wires?

 

Edited October 9, 20204 yr by chaseincats

Update for you guys.  I created a bypass switch to enable high-altitude mode using a standard flip switch and two spade connectors (one plugged into each of the plug's 2 sockets).  I gave it a quick test and it seems to be working (after confirming continuity).

If your bypass switch is working, you will notice the following with the car warmed up and any vacuum line unplugged:

• Switch on: the car should have a fairly noticeable stumble
• Switch off: the car should have a mild stumble if at all

On 11/27/2020 at 5:05 PM, chaseincats said:

If your bypass switch is working, you will notice the following with the car warmed up and any vacuum line unplugged:

If I did that, I'm pretty sure the engine would stall.  Would you please explain what "any vacuum line unplugged" means?