MSD ignition: DTC 21 + timing off scale

[WalknBullzEye]

Currenlty I removed the original Nissan inductive ignition and replaced it by the MSD 6A capacitive ignition.

It is easy to install;
+ from battery to MSD
- from battery or chassis to MSD
+ from MSD to coil
- from MSD to coil
+ wire from original coil to MSD (switched 12V)
- wire from original coil to MSD (signal from original ignition module)



This is how the MSD manual wants you to connect it. And it works! But now I constantly get a DTC 21: IGNITION SIGNAL PRIMARY

So I removed the original ignition module and connected pen 1 from the ECU to the MSD signal wire:


Unfortunately this does not work, no spark. So I must use the original ignition module.

Any thoughts how to get rid of DTC 21? Or is that impossible?

[Matt]

Probably impossible. Hardware is looking for specific feedback from ignition with the factory coil. I'm not sure on the specifics but once you move to different units you will get that code

[bachig24u]

Is this what you've done?

msd.jpg

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[WalknBullzEye]

Is this what you've done?

msd.jpg

I did not cut any wires.

I removed the 2-pins connector from the original coil wire and soldered them to the MSD wires. One is 12V switched and the other (MSD color: white, like in your picture) is the coil negative (-) wire.

[WalknBullzEye]

So problem one is DTC 21 with the MSD ignition.

Unfortunately there is also a second problem with the timing adjustment.

Normaly you can advance timing from 0 to 20 by turning the "ignition house", with 15 degree at its default setting. With MSD I can't get it further than 0 degree! Starting at -10 degree. See the picture below. I can't adjust it any further and it's currently at 0 degree:



I always use the following steps before adjusting the timing:

1. Engine must be at temperature
2. Lock the ignition timing with Nissan Datascan. This option is called "timing mode" in Nissan Datascan
3. Adjust the base idle to 800-900 RPM by turning the screw in the IACV/AAC valve
4. Adjust the timing by turning the "ignitoon house" and ofcourse a strobe light
5. Never adjust when the cooling fan(s) is/are on

I can't find much SR engines with MSD. Am I really the only one with the timing and DTC 21 problem?

[bachig24u]

It sounds like the timing belt/chain is off a tooth or the distributor is out a tooth. even the distributor chopper disc can cause it if its wrong way up.

It's hard to tell as I don't know how many teeth are on the pulleys/gears but if you are 15 degrees off in an RB then the chances are its out 2 teeth on the exhaust cam. one tooth on the distributor is alot more, usually 30-40degrees. enough to fire but sometimes cause a miss.

[WalknBullzEye]

I already knew, but double checked it. Timing chain is 100% OK

Distributor and exhaust cam can only be mounted one way.

[bachig24u]

When the engine is at 4000rpm does the spark timing line up with ECU advance?

[WalknBullzEye]

At 4000 RPM (in neutral) the timing is arround 26 degree in advance (in NIStune). Is that what you mean?

I really think the MSD is too slow and creates some sort of lag. Want to try an original coil first and see what the ignition does.

[bachig24u]

Does the timing in nistune consult gauges correspond to the timing light indication on the harmonic balancer at 4000?

if not, can you confirm that TDC is correct on harmonic balancer by
rotating the engine until no.1 piston is at TDC using a dial indicator gauge and then confirm that the TDC mark (0 deg) on harmonic balancer is lining up with timing reference point on engine.

[WalknBullzEye]

Today I tried to get the timing right, with the MSD ignition on my SR20DE highport + GT2871R.

Parts used, all new:
- MSD 6A (red box)
- MSD Blaster coil
- MSD spark plug cables
- NGK BCPR7ES spark plugs
- OEM distributor cap

With warm engine I locked the timing with Nissan Datascan (by the way, why isn't this option in NIStune? It's really handy when it comes to timing adjustments):


Second, I adjusted the idle screw untill the idle RPM reached 850.

Third and last I adjusted the timing by turning the distributor cap. Unfortunately it is not possible to set the timing at 15 degree BEFORE top dead centre. It can only be adjusted in a range of 0 to 15 degree AFTER top dead centre.

See the picture and video link below:

Video of timing: https://www.youtube.com/watch?v=-AGrIDh ... e=youtu.be



Is there anyone who has experience with MSD on his or her SR20 engine? Any solutions, thoughts? All welcome
Remember, this problem started after the new MSD ignition was installed.

Before tuning on the dyno I really want the timing to be correct. 15 degree at the crank must also be 15 degree in the ECU/NIStune.

Do I need to weld/adjust the aluminum ignition house so it can be adjusted in a larger range, or is there another option?

[Matt]

Nistune has timing advance under Operations > Active tests. Set the timing number, and then press 'start' and it will set base timing

When setting the timing, the FSM (factory service manual) says to disconnect the TPS so that it does not do 'closed loop idle'

the timing in the software is always before top dead centre (marks at crank start from 0 BDTC) and say 15 BDTC must match what timing in consult reports (eg 15 BDTC reported by ECU) for a match

DTC21 is expected once you remove factory coils and use aftermarket systems. The Nissan system looks at coil feedback and expects a particular current response from the coils. If it differs from factory you will get the DTC. It does not impact coil operation however

[WalknBullzEye]

Found the base timing option in NIStune, thanks.

I now have tried to set the timing like you/FSM says, in "open loop idle".
Again same result. Timing can be adjusted from 0 to 15 degree after top dead centre, which is too late.

I read the MSD manual again and found something:

The MSD produces full power multiple sparks for each firing of a plug. The number of multiple sparks
that occur decreases as rpm increases, however the spark series always lasts for 20° of crankshaft
rotation. Above 3,000 rpm there is simply not enough “time” to fire the spark plug more than once,
so there is only one powerful spark

Note: Do not use digital or dial-back timing lights.

So at idle, there are multiple sparks for each firing and the manual says to not use timing lights. Weird, how can I adjust timing without timing light?
I will contact MSD first and let you know. I really think this may cause the timing problem. Or this is no problem and timing is right, but seems offscale.

[Matt]

Put original coil back on and set timing with this, when once you know timing is correct then put MSD system back in

I dont understand how it could be after TDC?

[WalknBullzEye]

Problem solved. It was caused by a bad timing light, which I only used the second time (with MSD).