resest problem solved :-)
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resest problem solved :-)
given the number of posts on this issue I thought I'd start a new thread on what cured mine.
Rover V8, 4 coil lost spark, 60-2 trigger with Bosch VR sensor.
I had multiple and consistent reset issues on low revs, below about 1500 rpm and also consistenlty when I just tweaked the throttle at tickover.
My cure was fitting a 25uF capacitor on the +12V supply and earth, to the coils right on the +ve connector to the coil.
My earths are all connected to one point apart from the coil earth which is connected to the engine heads and I have multiple earths connecting the engine to the frame.
I've driven my car twice now and left it ticking over for 20 minutes and had zero resets I would have expected at least 60 resets during this period so I think I can say pretty comfortably it's cured.
Kev
Rover V8, 4 coil lost spark, 60-2 trigger with Bosch VR sensor.
I had multiple and consistent reset issues on low revs, below about 1500 rpm and also consistenlty when I just tweaked the throttle at tickover.
My cure was fitting a 25uF capacitor on the +12V supply and earth, to the coils right on the +ve connector to the coil.
My earths are all connected to one point apart from the coil earth which is connected to the engine heads and I have multiple earths connecting the engine to the frame.
I've driven my car twice now and left it ticking over for 20 minutes and had zero resets I would have expected at least 60 resets during this period so I think I can say pretty comfortably it's cured.
Kev
Re: resest problem solved :-)
That makes perfect sense as many factory coils (such as the Ford EDIS system) have a ~25uF capacitor on the coil (+) feed. They are usually attached to the coil mounting bracket and are commonly called Radio or EMI suppressors. Good call!Kev wrote:... My cure was fitting a 25uF capacitor on the +12V supply and earth, to the coils right on the +ve connector to the coil. ...
David
If the theory is correct and they are decoupling the supply from reverse spikes then it needs to be as close as possible to the coil and not at the MS end. Can't you just connect across the coil+ve to ground without breaking into your cable?mkehler wrote:I assume it won't matter where they are placed? either close to the coil, or close to the megasquirt? I'd rather put them on the MS end, instead of ripping apart my nice factory shielded cable with the factory eyelets right at the coil.
thanks guys!
Matt
Sorry I don't know your background so excuse me if this is obvious but be aware that you connect the cap from +ve to ground, it doesn't go in series with anything. Also the cap should probably be non-polar ie not electrolytic.
Kev
FORD EDIS caps
Agree with Kev regarding placing and type of cap . As close on the + fed to the coil as possible and a very shorth earth lead is the way to go.
Ford has it abt 15 "wire"cm away from the coilpack +contact and earth is bolted directly to chassis ( at least in the three EDIS engine looms I just dissected to get hold of the shielded VR cable with VR contact)
And on all these three EDIS 8 kits the cap at each coil was FORD number
F6AF 18801-AA , measured to be 0,25 µF . Probably metal polyester type .
The size makes sense in order to reduce RFI , a 0,25µF cap has lower impedance in the high-frequency spectrum than a 25 µF electrolytic.
So for RFI and reset woes , I believe a 0,1 to 0,5 µF MP cap at each coilpack plus to ground is the right solution.
Heribert
Ford has it abt 15 "wire"cm away from the coilpack +contact and earth is bolted directly to chassis ( at least in the three EDIS engine looms I just dissected to get hold of the shielded VR cable with VR contact)
And on all these three EDIS 8 kits the cap at each coil was FORD number
F6AF 18801-AA , measured to be 0,25 µF . Probably metal polyester type .
The size makes sense in order to reduce RFI , a 0,25µF cap has lower impedance in the high-frequency spectrum than a 25 µF electrolytic.
So for RFI and reset woes , I believe a 0,1 to 0,5 µF MP cap at each coilpack plus to ground is the right solution.
Heribert
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Hi all,
well I tried the resistive plugs on a car I was having a nightmare to cure the resets on and it has cured that, but then Kev did the same and it didnt cure it for him so I started looking in to it a bit further and as you say, Ford put the cap on their coil packs, I actually found it on a Megajolt diagram, so it looks like its cured Kev's, so hopefully a good earth, resistive plugs and a 25uF cap (dont think an electrolitic is suitable) on the +12V to the coils and to ground could cure a lot of these problems,
Phil
well I tried the resistive plugs on a car I was having a nightmare to cure the resets on and it has cured that, but then Kev did the same and it didnt cure it for him so I started looking in to it a bit further and as you say, Ford put the cap on their coil packs, I actually found it on a Megajolt diagram, so it looks like its cured Kev's, so hopefully a good earth, resistive plugs and a 25uF cap (dont think an electrolitic is suitable) on the +12V to the coils and to ground could cure a lot of these problems,
Phil
http://www.msextra.com/manuals/MS_Extra ... _Index.htm for MS1 Extra Manuals
http://www.msextra.com/ms2extra/ for MS2-Extra Manuals
http://www.extraefi.co.uk/cobra/accobra.htm 5.0L TVR powered Cobra Replica (MSnS-E)
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Go to a scrap yard and get the one Ford had made. They are attached to the coilpack mounting bracket and are a square plastic box.
James
James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk
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Go to a Ford dealers then. Escorts, Fiestas, Mondeos all have them. Likely newer stuff too.
A part from Maplin can likely be made to work but it doesn't have bolt holes and connectors to automotive standards for underbonnet use.
James
A part from Maplin can likely be made to work but it doesn't have bolt holes and connectors to automotive standards for underbonnet use.
James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk
My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
65looter wrote:Could you point me to one, I looked on the Maplin website but they have so many different ones , cheersdaxtojeiro wrote: a 25uF cap (dont think an electrolitic is suitable) on the +12V to the coils and to ground
The only suitable Maplins ones I could find were either 20uF or 30UF motor run capacitors, a bit ott for this application. Rapid electronics only have one also ott http://www.rapidonline.com/productinfo. ... leno=62525
http://www.falcon-acoustics.co.uk/ have a 25uF 400v one at 4.99.
http://rswww.com/cgi-bin/bv/rswww/searc ... cheID=ukie
https://secure.wilmslow-audio.co.uk/aca ... CR_49.html looks ok but typical of this firm very expensive.
Any of the 25uF listed should be OK depending on where you can order from. Alternatively scrap yard will be cheaper
Kev