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So has anyone ever had any probs with the Pfc control of ignition advance etc.

I appear to be having probs with the base ignition being way off. So everywhere in the rev range the thing is advanced 18 degrees over what the handset says is being run...and you cant wind the crank angle sensor back any more?

So whats the go, initialise the tune and start from scratch and hope that re-setting the ECU does the trick?

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Hi Troy, the Power FC assumes that the base timing is set correctly, if it isn't then you get what you describe. This is what I do, set timing with timing light, make sure CAS is ~central in the bolt holes. If not, then the exhaust camshaft pulley is one tooth out on the belt. Fix that, so that the CAS is ~central at 15 degrees BTDC at idle. Then tune the Power FC ignition maps on the dyno. To check, I reconnect the timing light and make sure that at around 2,000 rpm the timing, as indicated by the Power FC, is the same as that showing with the timing light.

Hope that helps :(

So if the handset is reading '0' then the Pfc isnt adding or reducing any ignition from the base timing ?!?!? Thats how i understand it works, so when the Pfc reads 25 deg then its actually 25 + 15 (15 being base timing?) or is it 25=15+10 and only adding 10 degrees????

I think my timing belt is a couple of teeth out. Ill have a look tonight after work.

Nah the thing isnt detonating...and it wasnt me that caused the problems this time:thumbsup:

It is idling like a pig and missing pretty bad, and knock level is getting up around the 40s but it isnt audily pinging.

I think i might get a ported carbie rotor...no cams and no injection....have any sitting in the yard:)

From what i understand knock levels up to the 40s isnt too alarming. Definetely doesnt mean your base timing is definitly out... can be as simple sa a bit of mechanical noise.

Bu tin my carse the popping and farting at idle is apparently the fuel and ignition that the Pfc is throwing at the engine

So if the handset is reading '0' then the Pfc isnt adding or reducing any ignition from the base timing ?!?!? Thats how i understand it works, so when the Pfc reads 25 deg then its actually 25 + 15 (15 being base timing?) or is it 25=15+10 and only adding 10 degrees????

I think my timing belt is a couple of teeth out. Ill have a look tonight after work.

I think you'll find that when the PFC reads 25 deg the timing should be 25 deg

Its not the injectors thats the prob...its the ignition timing.

So when im looking at the monitor menu what should the igniotion read at idle - 15 deg

Then when i go to the ign/inj menu on the settings at idle what should it read there for the three ignition parameters.

The top one is if you want to remove ignition from the whoel map, so should be '0'

The second line is for Map, which at idle should read '15'

I cant remember the third but i think its the difference between setting 1 and setting 2.

Any thoughts....

Are you sure the timing light is measuring correctly? My experience has been that using the loop near the ignitor module, the timing light seemed to read double the actual timing.

Using the "insert spark plug lead under #1 coil" seems to be the safest way to get a true timing value. Although, I read recently that if you lock the slidy bit of the timing light pickup back out of the way, then the loop works correctly.

Ok Roy I just went and looked at my setting's and came up with

Adj - '0'

Map - '15'

Fin - '15'

and the timing at idle jumps between '16','17','18' and '19' I hope this works for you dude if not and you want to know more settings no probs.

p.s I've never ever checked the timing with a timing light :cheers:

We had the same drama as blind_elk... That loop in the loom caused problems. The INJ/IGN is purely for testing if you want to index your whole map by 5deg then the thing will look like this;

Adj - '+5'

Map - '15'

Fin - '20'

or

Adj - '-5'

Map - '15'

Fin - '10'

In this screen the "Fin" is your actual timing, the "Map" is the number in the node position. Turn off ign and it resets to default.

In Monitor mode your HC should mirror your timing light.

good luck

Ciao

TT

In Monitor mode your HC should mirror your timing light.

Oh yes, so you would think. What you posted would seem exactly right. But for some reason whgen the handset says, say 15deg, the timing light says a little ofer 30, (the final number is 18 degrees over what the handset says:confused:

The only thing i can think of is the mechanic made a woopsie when they installed the tining belt and the exhaust wheel is a tooth or two off. So the PFC via the crank angle sensor and exhasut cam is reading one thing, then the crank a few teeth out of wack is reading another?!?!?!?!?!!?!?!?!

If i wind 18 degrees out of the whole map on the ign/inj map then the timing light reads the correct level of 15 degrees and the car idles properly without all the popping and farting.

So any other possible causes other then the exhaust cam being out of alignment. Surely a 500km old PFC isnt going to all of a sudden get this sort of fault?

I have some timing issues with my PFC as well. I set my base timing to 15 degree's. If you unplug your TPS connector the PFC will read 15 degree's. So whatever it reads is where the timing should be. Now if I set it to read 15 degree the car runs really bad. It's slow as hell. But if I set it to 25-30 (about double what it should be) it runs fine and knock never goes about 20. It will read 12-14 with light throttle while cruising which I think it mechanical noise. Once a week after a hard pull it will show 25-35 but that's about it.

My guess is that the timing leed I am using read double.

Hi guys, timing on a Skyline can be a pain this is what I do to make sure the signal is pure......

I take the #1 coil right off and lay it on the cam cover. I them stick a piece of insulated wire inside the coil (like it was a spark plug) so it makes contact. I connect the other end of the wire to the spark plug. I loop the sensor from the timing light around the piece of wire. That way you get a nice clean signal from only 1 cylinder, with no delay (light flashes exactly when the plug fires).

Hope that helps :wavey:

Yeh i understand the timing light reading could be a bit wooly and hence the error/double base timing.

But how does that allow for the fact that when the car is turned on it reads 15 on the handset and 15+18 deg with a timing light. So this could be double, OK. But the thing is idling liek a pig, idlingway high and driving like a piece of sh1t. When you retard the whole map by 18deg the thing idles properly at 900rpm with no miss, and the thing drives really nice.

This suggests that perhaps the timing light isnt reading double, but i will give blind_elk / SK method a go. But i suspect its more an alignment between the exhaust cam and crank as to why the timing is way out, and the driveability is up the clacker...

Have you also checked the timing at something other than idle? Give it a bit of throttle up to, say, 2k, and compare the timing with light / PFC. Do you still get the same disparity between the light and the PFC?

Is there any sort of offset adjustment in the PFC, like there is in the Wolf for example? (Wolf expects an initial trigger @ 60 BTDC, and you can adjust that value so that the Wolf and the timing light agree)

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