First startup of a KA24DE, clycling up and down

[grannyknot]

Just got the KA24DE engine swap started today and run into a couple problems,  first, the engine won't start by turning the key, it only starts by turning the key to ON and using a remote hand switch on the starter?

Then once it has started the revs seem normal until the engine warms up then the revs take off to 1500-2000 and the engine cycles up and down, it's not hunting, the cycle is predictable.

Any help would be appreciated, thanks.

 

[grannyknot]

A few more clues, while the engine is warming up and the revs are pretty normal and steady if I unplug the MAF the engine will increase the revs by 400-500rpm, once the engine is warmed up and it starts the cycling unplugging the MAF makes no change in the revs.

Still have to use the remote to start the engine but while I'm cranking with the key the fuel pump is on but the amber led light on the CanAm box for the RUN relay turns off, I think that is the culprit.  Maybe I should post this on the CanAm box thread.

[thisismatt]

Not uncommon for the ignition switch to lose/drop the run connection in start due to a worn/dirty switch.

 

What year is the ka? N/m, 91...

Edited June 27, 2021 by thisismatt

[grannyknot]

1 hour ago, thisismatt said:

Not uncommon for the ignition switch to lose/drop the run connection in start due to a worn/dirty switch.

 

What year is the ka? N/m, 91...

I took apart the ignition switch today and cleaned it out and used fine sand paper on the contacts, tested the continuity in ACC, ON and start, seems to be working fine.

In order for the engine to start doesn't the RUN circuit on the canam box need to be active? I guess in a pinch I could hook up a dash mounted push button start but I would rather fix the wiring problem if I can.

[demo243]

34 minutes ago, grannyknot said:

I took apart the ignition switch today and cleaned it out and used fine sand paper on the contacts, tested the continuity in ACC, ON and start, seems to be working fine.

In order for the engine to start doesn't the RUN circuit on the canam box need to be active? I guess in a pinch I could hook up a dash mounted push button start but I would rather fix the wiring problem if I can.

Stock ignition switch?

 

did you rewire the car?

 

If I remember I had to splice to of the wires off the stock ignition switch to make sure the can am board kept power on the 620 and the mega jolt board on the 510 - but I rewired both. 

[thisismatt]

Where did you pull the run power from?

[grannyknot]

2 hours ago, demo243 said:

Stock ignition switch?

 

did you rewire the car?

 

If I remember I had to splice to of the wires off the stock ignition switch to make sure the can am board kept power on the 620 and the mega jolt board on the 510 - but I rewired both. 

Yes stock ignition switch, the stock wiring harness was gone through and connectors in bad shape were replaced but there wasn't a lot of crossover between the 510 harness and the 240sx engine harness, they are largely separate.

1 hour ago, thisismatt said:

Where did you pull the run power from?

Good question, it should be the same dedicated power line that is running the FP and ECCS but looking at the diagram the ground wire for RUN is the old coil wire black w/white stripe, that's worth tracking down.

Thanks guys, some possibilities to hunt down

[demo243]

34 minutes ago, grannyknot said:

Yes stock ignition switch, the stock wiring harness was gone through and connectors in bad shape were replaced but there wasn't a lot of crossover between the 510 harness and the 240sx engine harness, they are largely separate.

Good question, it should be the same dedicated power line that is running the FP and ECCS but looking at the diagram the ground wire for RUN is the old coil wire black w/white stripe, that's worth tracking down.

Thanks guys, some possibilities to hunt down

They should be almost entirely separate- that’s the beauty of the can am board- make sure your not cutting power during cranking, the most likely issue for needing the remote start.

[grannyknot]

On 6/27/2021 at 9:42 PM, grannyknot said:

Good question, it should be the same dedicated power line that is running the FP and ECCS but looking at the diagram the ground wire for RUN is the old coil wire black w/white stripe, that's worth tracking down.

Thanks guys, some possibilities to hunt down

Okay, this is wrong, what I said above is not correct. The old Blk/Wh coil wire is actually the KEY PWR, the GND wire is straight from the body ground, the IACV goes to RUN 1 and #36 ignition from the ECU goes to RUN 2  So I think the wiring is all correct the problem seems to be the Blk/Wh wire isn't getting power while in the start position, not sure why.  I may have to find a different source for the KEY pwr if I can't figure it out.

[thisismatt]

There should be BW and BL(blue), where BW has power in both RUN & START, and BL has power only in START to bypass the coil ballast resistor for a hotter spark at starting.  BW shouldn't be losing power, but a work around would be to tie BL to BW.