Crank angle sensor and Power FC

campbellju

Moderators
Staff member
Quick update, I only got the scope on at 11pm last night in the end.

On both ECU's the 90deg pulse is square and goes from 0 to 5V
On the old ECU, the 1deg pulse is square and goes from 0 to 4V
On the PowerFC, the 1deg pulse is square and goes from 0 to 5V

Next step, with more time, is to test the CAS in isolation. Also I want to
trouble shoot back to the ECU in case the signal is less square there.
I also want to check whether it is getting all the 90 and 1deg pulses
===========================================

To the non-geek

It sounds fecked but it looks like it might be working
 

zia

Active Member
i was going to mention that you were barking up the wrong tree, but didn,t want to be impolite!!

zia
 

campbellju

Moderators
Staff member
Probelm is Zia I've been barking up an entire forest recently and still can't find anything technically wrong. Any suggestions greatfully accepted. :wink:
 

zia

Active Member
so what was the basic problem again. standard ecu plugged in all fine no problem whatsoever...correct?
plug in power fc...and doesn't idle and missfire......correct? any other change's still running standard maf/inj ?
running on default map on fc?or custom mapped?

zia
oh is power fc gtir specific ?
 
A

AJ4

Guest
come to think of it, I had exactly the same problem at one time, but it was because the PFC was set to use the Apexi boost kit and I was using a Profec B. After that it was fine...
 

campbellju

Moderators
Staff member
If only it were that easy. :( :(

Standard injectlors, MAF, dizzy, boost, Magnecor leads, coil and new lambda though it won't make a difference.
Taken it to RC Developments, they verified the FC on another car and no problem. Advised it was an electrical incompatibility or tolerance causing the issue. Meaning the standard ECU is less sensitive or more forgiving to whatever has happened. At that point the Power FC was still running but wouldn't go past 2000rpm. No boost controller and no AAC though been told by RC that shouldn't matter. Clive advised I start swapping bits around in my time rather than at his expense (very fair)

Tested a local owners:
standard leads, TPS, MAF, power transistor, coil no change past 2000rpm

Ripped out entire dash as advised problem is rev related and could be anything from HT leads to rpm counter.

renewed all earths, swapped over ECU's umpteen times. Troubleshot my way through the Nissan manual tested all the sensors individually and all work. Continuiuty checked all the sensor wires to ECU and no problems.

About 6 months ago, Ross had kindly photo'd all the Powerfc settings and posted up for me to check.

I had purchased a complete boost controller kit in the end (Against Ross's advice) and this makes no difference to the situation.

Somewhere in the middle, the problem has got worse :roll: as the car won't even start on the FC now.

The only slight technical funny in the Nissan checks was the CAS and that is why I posted.

I can manually roate the CAS and on the standard ECU, the 4 plugs fire but more importantly, the 4 injectors do too and the fuel pump keeps adding more fuel to compensate. This is repeatable for every "single" turn of the disc.

On the PowerFC, No 1 cylinder occasionaly fires, sometimes once for every turn and sometimes once for every 4 turns. The fuel pump does occasionaly work to showing that the injectors are firing occasionaly. And I've taken the plugs out and can get all 4 to spark but the order often goes back to plug 1. On the disc there is 1 longer slot (TDC?) that i'm guessing is the reference point and why it might keep firing cylinder 1?

My gut feel is its either the output from the CAS or what the PowerFC is doing with it but there is not a lot else to go at.

Like I said before, other tress to bark up are gratefully accepted
 
A

AJ4

Guest
campbellju said:
I had purchased a complete boost controller kit in the end (Against Ross's advice)
why did I say not to buy a boost controller ? can't remember :oops: :D
 

Nigell_d6

New Member
Hi,

Did you say you have you checked your power FC on another car, I dont run this one but it seems to me from what you have said the CAS and ECU coupled is ok, but power FC not, I accept that you have some sort of fault when in the system as this is showing up however does the fault show with the power fc disconnected ?

Regards

Nigel
 

campbellju

Moderators
Staff member
Ross, it was on the tech forum I was talking with you about Boost controllers and the problems with using the FC boost controller on a 2Bar sensor meant you needed to buy the full kit but then you would always need to have the commander to change from hi to lo boost etc and the boost controller you use was as good and cheaper etc. In the end I got a good deal from Matty on the kit but still agree with you on the disadvantages. Not a biggy anyway 8)

For the record, my PowerFC pro has been seen working in another car and RC Developments tried a standard PFC in my car and it had identiacal symptoms.

Update from last night :)
=================
On the standard ECU I am getting a good square wave to the ECU plug and I could see the 90deg and 1deg pulse quite clearly and watch them change with revs.

I ran the car for about 15mins as it needed clearing after squirting loads of petrol in manually.

Swapped to the Power FC and the car started again this time :D but would still not rev past 1000rpm. The pulsed squarewave from the CAS was very similar to before but not as clean on the scope due to lumpy idling. The 90 deg signal seemed to correspond with the signal for the standard ECU and looked like it was in the same proportion to the standard ECU.

Conclusion, the CAS is sending out all the right signals to the ECU with nice square waves at 1000rpm. I know need another tree to start barking up.

The car is misfiring so badly it is as if the the timing on the engine is just so badly wrong or offset that the car doesn't ignite sometimes.
Could it be the timing on the car? Do I have to check the timing on the TDC when installing the PFC? MY standard ECU is not completely standard so could this have a timing offset???

I realise this is all getting a bit illogical but I am running out of logical things to check.

My next tree to bark up is the plugs back to ECU again. Double check everything again. :( Thanks for all your support so far.

Jim
 
A

AJ4

Guest
its a good idea to set your advance so it ties up with the PFC. Its possible to have them different... :shock: At least if they correspond from the start then you know where you are and can just read the commander rather than having to check with a strobe all the time.


I must admit when I did mine it was only about 1 degree out, not enough to cause your kind of problems though.

Disconnect the TPS, and adjust the timing so it ties up with the PFC.
 

zia

Active Member
well this has to be the brain tickler of the season,seem quite contradictory,where for instance moving the dizzy by hand should give exactly same spark/inj pulse no matter what ecu was connected.my advice is you have two option's either somewhere along the line the signal is degrading to the powerfc or causing incorrect reading/ resistance (but if you checked the wire then this cancel's that one out). fit the power fc on another car note the duration of the pulse for cas and have look in setting that it is not changeing of it's own accord.run the car make sure the power fc is 100% working don't take somebody else word just varify what they say.and check by manual turning of cas that inj/spark occur's
last resort would be to sell power fc and seek alternative, sometime cost/ time involved in trying to achieve is not worth it.

zia
 

campbellju

Moderators
Staff member
zia said:
last resort would be to sell power fc and seek alternative, sometime cost/ time involved in trying to achieve is not worth it.

zia
You've already spotted my plan B then :wink: :lol: :lol:

Cheers Zia.
Jim
 

campbellju

Moderators
Staff member
:whoo: :whoo: :humble: :humble: :peace: :rockon: :rockon: :rockon: :cheer2: :cheer2: :cheer2: :drum: :thumbsup: :thumbsup:


It was the crank angle sensor after all. Standard ECU likes it, PFC hates it. I can't be bothered to put my scope on to find out why cos its FOOKING WORKING and I'll only bore people to death with mindless ramblings about square waves and one reading 4V whilst the other reads 5V.

Put it all back together again and get it booked into RC, 400ish bhp here I come.

Looks like I'll have a Japanese car for JAE this year and might be able to do that track day for my birthday in 6 weeks.

Do I sound pleased? Its cos I'm over the moon!!

Jim
 

stevepudney

GTiROC CHAIRMAN
Staff member
Well done mate, more patience than me thats for sure.

Will be good to meet you at JAE, this year.

Steve
 
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