CPR Hard Start, back fires, and random misfire

Hondata CPR (Coil Pack Retrofit) support
TurboChuck
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Joined: Wed Jun 10, 2015 9:25 am

CPR Hard Start, back fires, and random misfire

Post by TurboChuck »

Setup - CPR installed on fully built B18C1 in a 96 civic sedan. K20 coils, S300V3

Issues - Car is very very hard to start and back fires like crazy while trying to start. It will stumble and fire up but only after cranking and cranking. Sometimes it wont start at all just back fires. Once car starts it runs decent not great but with a random mis or stumble. Does not matter if hot or cold. Twice when driving coming to a stop the car shut off and would not re-start. Stopped driving since then so we don't get stranded.

Red/green/yellow lights all come on or blink on CPR box
Timing is dead on
Checked wiring 10 times
Grounds are all correct
OEM dizzy
Now have stock dizzy/plug wire setup on car and works perfect. Fires right up.

I've read through all threads with issues resembling mine and tried almost everything. I have not tried a new ECU since it works perfect with stock dizzy setup and Im not going to just throw money/parts at a problem.

Any help would be appreciated.

Update:

So finally got COP to work. Took buying 3 good used distributors what worked great but not with COP then as a last ditch effort bought a OEM néw one.....it worked.

Progress has been made but now I have random misfires/stumbles. My commute is 26 miles and some days it happens on and off the entire way other days it never happens. Put dizzy back together and never happens so it's the COP. Second issue is spark is weak. Stock dizzy has at least twice as much spark. Had to gap plugs to .016 for 550whp @22psi. Car would break up with any larger gap so hopefully that shows how weak spark is.

Any suggestions Hondata?
Last edited by TurboChuck on Mon Nov 30, 2015 10:05 pm, edited 2 times in total.
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Spunkster
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Re: CPR Hard Start, back fires, and random misfire

Post by Spunkster »

IT would be a good idea to try an ECU from someone else that has a working CPR.

Does this have an OEM engine harness?
TurboChuck
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Joined: Wed Jun 10, 2015 9:25 am

Re: CPR Hard Start, back fires, and random misfire

Post by TurboChuck »

OEM harness and resistor plugs

I will try to find another ECU to try. I don't understand though how a ECU can work fine with every setup but the CPR? Are there certain ECU's or certain things about specific ECU's that don't allow the CPR to function correctly?
TurboChuck
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Joined: Wed Jun 10, 2015 9:25 am

Re: CPR Hard Start, back fires, and random misfire

Post by TurboChuck »

I have also noticed the spark generated by the coils is very weak compared to the spark generated by the dizzy/plug wires.
AREA876
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Re: CPR Hard Start, back fires, and random misfire

Post by AREA876 »

Which ECU, plug # and spark plug gap are you using
TurboChuck
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Joined: Wed Jun 10, 2015 9:25 am

Re: CPR Hard Start, back fires, and random misfire

Post by TurboChuck »

P28 ECU with S300V3. Plugs are BKR8EIX with .025" gap now. Going to re-gap to .020" once boost is turned up past the 3psi we have it set to now.
TurboChuck
Posts: 10
Joined: Wed Jun 10, 2015 9:25 am

Re: CPR Hard Start, back fires, and random misfire

Post by TurboChuck »

Spunkster wrote:IT would be a good idea to try an ECU from someone else that has a working CPR.

Does this have an OEM engine harness?

Any options other than another ECU since I do not have another one to try?
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Spunkster
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Re: CPR Hard Start, back fires, and random misfire

Post by Spunkster »

You need to use the process of elimination. Swapping ECUs is the best way to test this.
TurboChuck
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Joined: Wed Jun 10, 2015 9:25 am

Re: CPR Hard Start, back fires, and random misfire

Post by TurboChuck »

Working on trying to find an different ECU to test but until then maybe I can test a few other ideas? What would you have me do after i tested a different ECU and still had same issue?

What would cause such a weak spark with coils? Power to coils? Output from CRP box? Power into CPR box? Same amount of spark on each coil so its not like I have 4 bad OEM new coils. I'm willing to try anything. Do you have schematics for testing?

Did a break in dyno with dizzy/plug wires/same ECU and made 480whp & 350ft/lbs on 15psi. Running perfect.
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Spunkster
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Re: CPR Hard Start, back fires, and random misfire

Post by Spunkster »

Post a pictures of the engine bay showing the wiring and all the grounds in the engine bay.
TurboChuck
Posts: 10
Joined: Wed Jun 10, 2015 9:25 am

Re: CPR Hard Start, back fires, and random misfire

Post by TurboChuck »

So finally got COP to work. Took buying 3 good used distributors what worked great but not with COP then as a last ditch effort bought a OEM néw one.....it worked.

Progress has been made but now I have random misfires/stumbles. My commute is 26 miles and some days it happens on and off the entire way other days it never happens. Put dizzy back together and never happens so it's the COP. Second issue is spark is weak. Stock dizzy has at least twice as much spark. Had to gap plugs to .016 for 550whp @22psi. Car would break up with any larger gap so hopefully that shows how weak spark is.

Any suggestions Hondata?
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Spunkster
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Re: CPR Hard Start, back fires, and random misfire

Post by Spunkster »

Have you tried a different ECU?
TurboChuck
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Joined: Wed Jun 10, 2015 9:25 am

Re: CPR Hard Start, back fires, and random misfire

Post by TurboChuck »

No, I don't know anyone that I can borrow ECU from. Not sure why it would be the ECU it works flawless with the distributor/plug wire for 2 years. What would be bad with ECU that would work great with distributor but not with COP?

I will buy one from you and try it, if it does not fix the problem let me return for full refund? I have no problem spending money to fix the car but don't like just throwing parts at a problem.
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Spunkster
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Re: CPR Hard Start, back fires, and random misfire

Post by Spunkster »

We no longer sell ECU's. We have seen a number of people that a stock distributor still works but the ECU just does not like the CPR, and swapping ECUs fixes the problem.
TurboChuck
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Joined: Wed Jun 10, 2015 9:25 am

Re: CPR Hard Start, back fires, and random misfire

Post by TurboChuck »

For your customers that swapping the ECU fixed the problem what issues were they having? Similar?
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