ONLY 3 CYLINDERS FIRING ?

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c2turbo
Posts: 44
Joined: Mon Dec 26, 2011 11:26 pm
ECU Model: S80 Pro
Firmware Version: 89

ONLY 3 CYLINDERS FIRING ?

Post by c2turbo »

Hey guys I have an s80 on a single-plug Porsche 911 engine with just a crank sensor and COP's ( i have set the General settings to twin plug and amped cop's ) the engine is only running on 3 cylinders 1/6/2 and not 3/4/5 I have tested all the coils through Diag and they all are firing when testing and have pinned them out and toned them out to the ECU all the power wires have power and all the grounds have a good ground . when i start the engine it runs on the three cylinders then after i shut it off and go run the diag for the coils when i start the test it will backfire I am assuming through the three cylinders that are not firing when the engine is running?

the crank oscilloscope looks good and syncs with a clean 60-2

any ideas would be helpful

David
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: ONLY 3 CYLINDERS FIRING ?

Post by stevieturbo »

How have you wired the coils ? to what outputs ?

And have you verified spark on the latter 3 cylinders in terms of firing order ? They probably are firing, just at the wrong timed if wired incorrectly.
Rob Stevens
Posts: 1247
Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: ONLY 3 CYLINDERS FIRING ?

Post by Rob Stevens »

Wasted Spark
Use the lowest outputs. For a 6 cylinder engine with a firing
order of 1/3/6/4/5/2 wire as below.
Cyl 1 3 6
Cyl 4 5 2
O/P 1 2 3

Twin Spark
Depends on the number of cylinders. Say the engine is a six
cylinder, wasted spark, twin spark then 1,2 and 3 are plugs 1, 4,
5, 6 are plugs 2. Four a similar 4 cylinder the groupings are 1,2
are plugs 1, 3 and 4 are plugs 2. 8 cylinder wasted spark, twin
spark is the maximum allowed configuration.

You need to be sure on the firing order, not just cylinder number, can be contradictory sometimes!
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: ONLY 3 CYLINDERS FIRING ?

Post by stevieturbo »

as it's amplified COP, you probably could just use 1, 2 and 3 and pair wiring.

Can't remember for twin spark if it's OP 1, 2, 3 and then 5, 6 and 7.....or if the latter set follow 1, 2, 3 and then 4, 5 and 6.

I would definitely prefer the twin spark and wiring of one coil per output though
c2turbo
Posts: 44
Joined: Mon Dec 26, 2011 11:26 pm
ECU Model: S80 Pro
Firmware Version: 89

Re: ONLY 3 CYLINDERS FIRING ?

Post by c2turbo »

Thanks for all the responses my firing order is 1/6/2/4/3/5 I have the coil outputs wired as follows

This is the wiring for the coils on my S80
cyl 1 output 1 pin 10
cyl 6 output 2 pin 18
cyl 2 output 3 pin 1
cyl 4 output 4 pin 26
cyl 3 output 5 pin 11
cyl 5output 6 pin 27

so one output per COP ( note the first three cyl are firing the last three are not )as per the manual I have set the genreal settings to twin spark since i
only have a crank sensor fitted and all coils spark during diag test

thoughts ?


thanks again
David
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: ONLY 3 CYLINDERS FIRING ?

Post by stevieturbo »

I would check to see if you are getting spark on outputs 4,5,6.....as you might be getting the actual output on 5,6,7.

So you will have spark on two of those cylinders, at the wrong time.

I think you do need to use outputs 1,2,3 and 5,6,7.

I think...been many years ago.

The old P8 information explains this....S80 instructions seems to omit it.
dta cois p8.jpg
c2turbo
Posts: 44
Joined: Mon Dec 26, 2011 11:26 pm
ECU Model: S80 Pro
Firmware Version: 89

Re: ONLY 3 CYLINDERS FIRING ?

Post by c2turbo »

Thanks Steve I tried moving the outputs to 5/6/7 but got the same result the three cylinders are still stone cold. I am running out of ideas I may just have to add a cam sensor but it will not be easy with this setup and I have already built the harness for just crank sig only



let me know if you have any other ideas

thanks David
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: ONLY 3 CYLINDERS FIRING ?

Post by stevieturbo »

you should not need a cam sensor.

I ran my V8 for years on twin spark, crank only.

Exactly what coils are you using ?

Whilst you shouldn't need to, you could pair the coils to outputs 1,2,3.

More actual testing needed
c2turbo
Posts: 44
Joined: Mon Dec 26, 2011 11:26 pm
ECU Model: S80 Pro
Firmware Version: 89

Re: ONLY 3 CYLINDERS FIRING ?

Post by c2turbo »

I have run this setup wired the same way with 12 cop's and this ECU in the past wired to coil outputs 1-6 on a twin-turbo setup with the outputs paired with a pullup resistor and had good luck with it. pulled the ecu out to run in a different car and it is give me these issues.

The cop's are Denso 4 wire from a lexus 470 i believe


Thanks David
c2turbo
Posts: 44
Joined: Mon Dec 26, 2011 11:26 pm
ECU Model: S80 Pro
Firmware Version: 89

Re: ONLY 3 CYLINDERS FIRING ?

Post by c2turbo »

so after more testing, the first 3 outputs are triggering the coils and the second three outputs are not triggering they work in the Diag utility but not when running so I believe the issue is a software setting or firmware issue.

not sure what to do next I have tried twin spark with the wiring both ways as suggested above, is there another setting or requirement that i am missing?
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