Zetec Timing ???

julez · Post by **julez** » Fri Oct 03, 2008 9:02 pm

Hi guys

Just installed MjLj V4 to Ford 1.8 Zetec works well and communicates with laptop ok..
The engine is standard and the vr sensor is std and in std location, looking at standard marks on standard flywheel.

The Question i have is related to timing figures..

Found tdc with Gauge, and there is one notch on the front pulley that is in allignment with mark on sump..

Now what i cannot understand is that when i hook-up my timing light (snap on with digital advance and retard).

1: With Edis and NO MjLj, i have to advance timing light to 20 degres to align marks.

2: With MjLj connected, i have to advance light to 29 degres to align marks.

3: With MjLj and laptop connected, lifted revs a little and laptop says 24 advance But i read 47 on light.

Can someone advice on what is going on with my light (also revs on readout on my light seem to be doubled)

Thanks in advance

JULEZ

Big Vern · Post by **Big Vern** » Tue Oct 07, 2008 11:52 am

Edis is a wasted spark system ie the edis fires the coil pack as cyl 1 & 4 together then 2 & 3 together so your timing light is seeing twice as many pulses and therefore twice the spark advance and twice the RPM.

HTH Nigel

julez · Post by **julez** » Wed Oct 08, 2008 2:09 pm

are there any filters or the like that can be used with my timing light.
or does anyone know what timing lights work with the wasted spark system??

NITROPIXIE · Post by **NITROPIXIE** » Wed Oct 08, 2008 5:03 pm

i think most modern timing lights should work with the wasted spark system. Most of the time a timing light is used to set the timing at low rpm but will work to higher rpms. If you work it out, say you were setting the timing at idle about 850 rpm then the timing gun would see 1700 pulses. The gun should be able to cope with these sufficently. A cheap timing light from ebay can do upto 6000 rpm so upto 3000 rpm on the wasted spark system, i'm sure more expensive ones can do better.

I might be wrong but i wouldn't of thought you would see twice the advance on a wasted spark system as big vern says, yes twice the pulses/flashes but not twice the advance.

From what it sounds like it could be you have incorrect advance adjustment on your timing light or more modern zetec ecu's use 20 degrees advance as the norm instead of 10 degrees, but i can't be sure of this its just an hypothesis. Don't know if anyone can shed light on it?????

Alexander_Monday · Post by **Alexander_Monday** » Wed Oct 08, 2008 7:17 pm

The problem is the adjustable delay timing light. It figures the time needed to advance the spark based on the current rpm and delays the strobe accordingly. It thinks the rpm is double what it actually is becuase wasted spark has a spark per revolution instead of per 2 revolutions and delays 1/2 the time necessary for the advance. This is why you show double advance on the light. If you keep this in mind ( real advance is 1/2 what the timing light thinks ) then problem solved.

NITROPIXIE · Post by **NITROPIXIE** » Wed Oct 08, 2008 7:54 pm

That makes sense, sorry big vern i was wrong

NITROPIXIE · Post by **NITROPIXIE** » Wed Oct 08, 2008 8:04 pm

sorry to butt i on your thread julez, but does this mean that when i disconnect my megajolt and run just edis, and i read 12 degrees advance i'm really running 6 degrees?? i have a very standard timing light with no advance/retard settings or any other options.

I think i am running 12 degrees as the gun can't compensate for anything at all so it can't have error???

Alexander_Monday · Post by **Alexander_Monday** » Wed Oct 08, 2008 8:41 pm

A standard timing light does not have a delay circuit built in, so it should read correctly.
If the pickup is not polarity sensitive it will flash the strobe 180 degrees out of phase as
well as the standard flash, so you will be able to see the pulley at 180 degrees as well
as correctly oriented. As long as there are not any marks across the pulley from your
timing mark you will probably not even notice the extra strobe.

Big Vern · Post by **Big Vern** » Thu Oct 09, 2008 12:21 pm

If you are using the factory flywheel and crank sensor in their stanard locations the you actually have 10 degrees BTDC because that's how Ford designed it to work. For their limited operation strategy (LOS) the edis receives no signal from the ecu as it's being used purely to run the fuel injection so edis gives you 10 degrees btdc every where. It's your timing light that is giving you duff information.

HTH BV.

Big Vern · Post by **Big Vern** » Thu Oct 09, 2008 12:29 pm

As for Nitropixie's non adjustable timing light you are correct in that you should see twice the pulses but at the correct ign advance as your timing light is not trying to calculate when to flash! it just see's a trigger and flashes. My light however is adjustable and uses engine speed vs time to calculate the advance angle so as to display a value. When it see's twice the pulses it see's that as twice the speed so gives twice the advance angle as well. That latest types of timing light have a feature that allows you to select multispark.

HTH BV.