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Bypass ignition key cause limp mode?

It looks like it defaults to premium but you wouldn't get a premium light on gauge. When you run in regular mode it looks like you put a ground onto pin 20 of CDI module (pnk-blk wire) through the ignition switch. In premium mode that connection is not made so pin 20 is not grounded. When you disconnect the ignition switch there would be no ground on pin 20 so that is why I think you would default to premium mode.
 
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It looks like it defaults to premium but you wouldn't get a premium light on gauge. When you run in regular mode it looks like you put a ground onto pin 20 of CDI module (pnk-blk wire) through the ignition switch. In premium mode that connection is not made so pin 20 is not grounded. When you disconnect the ignition switch there would be no ground on pin 20 so that is why I think you would default to premium mode.

I think you may be right. Was doing some more research and looked at the wiring diagram. Makes sense.

I’ve swapped an 01 ignition onto a 98 xc, and it’s running like it’s stuck in limp mode. Just Trynna check all the possible problems.
 
I just read your other post in the Gen 1 section and you said you don't have the TPS sensor hooked up.
If you have the 01 CDI ignition box I'm pretty sure you need that sensor input.
 
I just read your other post in the Gen 1 section and you said you don't have the TPS sensor hooked up.
If you have the 01 CDI ignition box I'm pretty sure you need that sensor input.

From what I read it should still run. I do know of a couple that have been swapped the same as I have done and run.
 
Found a good article on how the tps and computer works.

After reading that it would make sense that the coolant sensor needs some heat to it or it will retard the timing.

I haven’t put it into a water jacket yet, looks like that will be the next thing I try.

955949C0-EE4F-4EA8-96A0-A1B3799A7004.png
 
I'd definitely swap the temp sensor and wire it up (I'm guessing the old setup is just a temp switch for the idiot light), and I'd swap carbs if need be to get TPS. Even if it'll run, I'm not sure what the point of the swap is without TPS, unless the ignition on the sled has failed and you're working from parts you have sitting around. Anyway, I looked at the wiring diagram, and I concur that the premium curve is the default, (assuming you have the TPS and temp sensor). There's one input for the kill switch, throttle safety circuit, and key off (pin 4). Switching the key to premium just turns on the "premium only" light; switching to "regular" grounds pin 20, telling the CDI to retard timing. Leave it disconnected for the hotter spark curve, ground it permanently for the more conservative curve, or wire up a switch (either the ignition switch from the newer sled, or a simple switch ground).
 
I wired up a coolant sensor the other day. Just have to swap it out with the dummy light sensor on the head light you said.

I was having problems with the ducatti stator, pieced this kokusan ignition together with stuff laying around. Figured it’s a better way to go in the long run.
 
Got back to it today for a bit.

It runs better, but still not right. I’m starting to think with no tps it’s getting to much timing once revved up.

It starts great, seems fairly snappy when you blip the throttle. But seems to fall on its face at 4500-5000 rpm.
 
Spent a little time on it again today. Got to checking some wiring I had modified.

Found it wasn’t reading the coolant sensor through the plug. Fixed up a couple wires.

Thing runs pretty lean. Will have to jet it up for sure, but it seems to run pretty strong for the little bit I ran it.
 
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