first off i apologize if this is in the wrong section, but i do have a turbo car and figured a lot of you guys use this unit anyways i was on the dyno the other day and at the start of the session the car was acting a little strange like it was firing on only 7 cylinders or so and the power showed it was down. we really struggled to find the issue as to why we were getting coil malfunction codes, finally we just unplugged the 2 step and bam it made really good power and the issue went away. I have searched this issue for a while on here and the answers have been extremely vague, and MSD is about worthless with their tech support, can anyone steer me in the right direction? I really like how this unit performs but im just really curious as to why it is screwing with the coils.

 

we run megasquirt and it runs everything, no MSD needed

 

How do you have it hooked up?? The msd 2 step works great very easy to hook up

 

Check for any bent pins with the connectors and also make sure the module is mounted away from big heat sources and vibration.

 

Then you aren't much help… why even post?

Send the unit into msd. It sounds like you found the problem. A lot of triggering is passed through the msd and if there is something wrong inside you will have problems as described. Call them, send it in and they will repair it. Or try it on another car and see if it does the same thing.

 

thanks for the responses guys, i will not be converting the car to megasquirt so that doesn't help me. I am using the blue wire as an activation wire. I made this unit its own bracket


do you guys see anything wrong with that?

 

Seems ok just gets a little warm there. So maybe I missed it but where are you connecting the blue wire to???

 

I've had issues with the msd cutting spark to all cylinders. They won't warranty or fix it either.

 

what was your solution? I really need a 2 step, this is a 1000 hp car. Its a shame because like i said it really works well when i activate it, but if its screwing with all my coils i need something different

 

i believe its connected to a relay.

 

Try mounting it somewhere else temporarily and see if the problems persist.

 

I had a time getting my MSD to work properly on my N/A setup.. I tried it a couple different ways wiring it to a 12v clutch signal at the CPP and the PCM without success, so I finally wired it to a switched ground on the CPP and it worked like a charm. When I get my new setup finished I'm ditching the MSD and going with a Lingenfelter LNC-2000...

 

point is get rid of the MSD not needed...have to many issues...

 

I realize this isn't our product but some of the same information applies and I am familiar enough with the MSD unit that I thought I might be able to be of help.

If you leave the MSD wired in (connected to the coils) but nothing connected to the activation, does it do the same thing?

If the answer is NO (problem doesn't happen with the activation input is not connected to anything) then the problem is probably related to the activation input itself.

If that is the case, look at how the activation is wired, what it is wired to etc. I think you mentioned a clutch switch. Which switch? If it is the cruise control disable switch at the top of the clutch travel on some GM vehicles then that switch tends to bounce around a lot, causing false momentary activation. We do not recommend connecting to that switch. You also mentioned a relay. Most relays are mechanical devices so extreme vibration or acceleration can sometimes cause them to switch on-off-on (or off-on-off) and cause false activation. We recommend using solid state relays in cars that are likely to see a lot of vibration or very high acceleration loads.

If you have access to a data acquisition system, storage type scope or even a digital volt meter with a max/min storage or capture mode, it might help diagnosing the problem if it is activation input related. You are looking for that input to switch on when it shouldn't. Keep in mind this might happen for a very brief amount of time and still cause a problem.

If the answer is YES (problem still exists when activation is not connected) then the problem isn't related to the activation input but likely to the 2-step itself (or the wiring to/from it).

The MSD, like the Lingenfelter 2-steps, is always in control of firing the coils since it is intercepting the signal that goes from the ECM/PCM to the coils. So if electrical noise is causing the MSD problems, it will impact the operation of the engine even when the 2-step isn't activated.

Things to check would be:

• Spark plugs - make sure you are running RESISTOR type spark plugs. Double check - a lot of incorrect information exists even on major web sites about some plugs being resistor plugs when they are not.
• Spark plug wires - make sure you are running wires that are shielded and low noise type wires. If you aren't sure or have tried other things, just try changing the spark plug wires (to a take off stock set for example). You would be surprised how many aftermarket spark plug wires generate significantly more electrical noise than the stock wires.
• Placement of the 2-step near electrically noisy devices (coils, fuel injectors, solenoids).
• Routing of wires to/from the 2-step along other wires (Don't do this. It looks nice but can induce electrical problems. If you have to route near/across fuel injector, ignition or other similar wires have them cross at 180 degrees and do NOT run them parallel to each other). Try re-routing the wires to and from the 2-step.

Hope this helps.

 

Jason,

Thanks for the response, there is no clutch switch this car has a th400 and its hooked to the trans brake. I do have this think sitting right over top of the injectors and harness, could that be an issue? I am currently running br7ef plugs which to my knowledge is a resistor style plug.

 

Yes, the BR7EF plugs are a resistor plug (according to the NGK chart I have).

I would try moving the unit away and see if it makes a difference (mount it somewhere else).

If you have a trans-brake, I would recommend installing a TVS diode on it. These should be available from a local performance shop, especially if they work with nitrous on motorcycles (that group seems to use them the most for some reason). The trans-brakes can generate very high voltage spikes that can damage electronic modules, including the 2-step.

 

Thanks Jason, So if I dont use the trans brake wire for a signal what do i use?

 

I didn't say not to use it for activation. Just said you should install a TVS diode across the trans brake.