A bedeviling tuning issue

Hello gang, I've got a head scratcher here for the tuning experts here in the group. Here goes:

When really wacking on the throttle (75-100% open) right as the rpms get to 6500 there is a momentary blip in the engine revs. It might only be one or two fires of the cylinders, and after the blip at 6500 things are normal. Any idea whats going on?

I'm running a PCV with Autotune and a full (2bung) Guzzitech exhaust with open airbox with GT map for the system.

Other than this tiny, yet annoying, issue the bike screams and produces fantastic power.

Any help from the experts is greatly appreciated.

Could be some glitch in base map but usually fixed by saving autotune stuff back in the PC5.
You might ask Todd over on GT forum. He sells the stuff. I have installed PC5/Autotune w/no issues.
To tune your engine you need to disconnect the PC stuff. When done tuning you hook it back up, then fix issues w/PC.

Although it's wise to occasionally save the autotune map back to the power commander, this probably won't help, as the autotune is active at all times and would be compensating for any glitches in the map.

I would be looking for a loose electrical connection, or perhaps the spark plug caps need replacing?

I'll take a punt Shanks, seeing this is your 1st post and you haven't posted up in the intro section.

The best advice you will get here is chuck ya PC autotune .................. and read up the following link.

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Pete, take ya meds and relax.

It's the PC-V. I guarantee it. I have personally experienced this. This is what it looks like on a dyno.

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Disconnect the Power Commander and it will stop.

Thanks for the tip Beetle. Yes my Dyno map looks quite similar. So whats the easiest way to temporarily turn off the PCV/AT? Can i just pull the power to it while it's still tapped and on the harness to test if the problem goes away? Have been wanting to turn off to test but not sure of the best method.

-Shanks

What sort of fuel economy are you getting just out of interest?

Unfortunately the PC is powered from the injectors. The only way to disable it is to disconnect the PC injector leads, and reconnect the original leads directly to the injectors.

Can't you load a zero map and from menus turn off the autotune? So it still powers up, just (supposedly) is a pass thru and not doing anything at that point.

usedtobefast wrote:

Can't you load a zero map and from menus turn off the autotune?  So it still powers up, just (supposedly) is a pass thru and not doing anything at that point.

Updates can be stored in the ECU map, the power commander, and the autotune. Going back to a stock map is not going to work well due to the changes to the airbox and exhaust.

Probably the best move to eliminate the power commander is to disconnect it entirely and load a Beetle map tuned for the airbox and exhaust mods.

I'd be keen to hear the results.

usedtobefast wrote:

Can't you load a zero map and from menus turn off the autotune?  So it still powers up, just (supposedly) is a pass thru and not doing anything at that point.

While this would render the PC ineffectual, It won't prevent the symptom. When I experienced this problem, I had a zero map in my PC. I don't know whether the fault is affecting the injectors or the TPS. The poxy things load down the TPS, which means IMNSHO, all Power Commanders should be hit with a very big hammer, immolated, then ground to bits in a mortar & pestle, poured into a toilet, then vigorously shit upon.

Just say it as you see it Mark .......

Doesn't seem to be a great friend of PCs, but I must agree. An accurately built map is the best You can do for Your GRiSO and the rest should be thrown away.

I have power commanders on nearly half my bikes (but not the GRiSO). They were installed when there was no other option, no guzzidiag, and expensive software just to reset the TPS.

Most also have the autotune option. The bikes run great, I see no reason to remove them. However, I doubt if I ever would buy another one.

Shanks,

If you want to be rid of your PC, send me your ECU map & PC map. I'll transpose the PC map values to the ECU map. Make sure to update the PC map with the Autotune values first.

armitage shanks wrote:

Thanks for the tip Beetle. Yes my Dyno map looks quite similar. So whats the easiest way to temporarily turn off the PCV/AT? Can i just pull the power to it while it's still tapped and on the harness to test if the problem goes away? Have been wanting to turn off to test but not sure of the best method.

-Shanks

Is a PCV with dyno tune useful on the 1200 8V SE ? Or is the Beetle map a better tool ? Can you explain/compare the benefits of both ?

There are no advantages to using a PCV.

The end.