Ms tacho issues
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As a matter of interest, did it work OK with your rev counter at all revs - and which model rev counter was it?Quagmire wrote:On mine, the relay buzzed all the time with the engine running, but I guess what the relay does is a factor of the spec and brand it is...
I've got Richard's MS here and have been having a play. The transistor driving the coil gets very hot indeed very quickly and the pulse the circuit produces reduces in level as this happens. I'd also expect the transistor to fail in time. Also not sure how long a chattering relay would last either.
All very odd, as this circuit is often mentioned on the MS forums as being a fix.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
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- Getting There
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- Joined: Sat Feb 14, 2009 11:04 pm
- Location: Yorkshire
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- Getting There
- Posts: 238
- Joined: Sat Feb 14, 2009 11:04 pm
- Location: Yorkshire
Do the tach blips and misfires occur at the same time?
If so you might have some kind of loss of sync error or MS reset going on.
Try running around and taking a datalog, see if you get anything.
If you do have something like that then its worth checking out the field called "Lost sync reason", the maximum value logged for that field will tell you what the reason is.
For example after rummaging around in my EDIS wiring I was getting what felt like resets, and it was lost sync reason code 15, which indicated I had upset the EDIS. I disconnected and remade all my connections and all was good again.
If so you might have some kind of loss of sync error or MS reset going on.
Try running around and taking a datalog, see if you get anything.
If you do have something like that then its worth checking out the field called "Lost sync reason", the maximum value logged for that field will tell you what the reason is.
For example after rummaging around in my EDIS wiring I was getting what felt like resets, and it was lost sync reason code 15, which indicated I had upset the EDIS. I disconnected and remade all my connections and all was good again.
1974 Rover 3500s
1984 3.5 90
1959 2.25 series 2
1984 3.5 90
1959 2.25 series 2
It was on soak test here for more than 24 hours driven from a Stim and on-line to the PC. Rock solid.
Where is the tach adaptor mounted? It produces a pretty vicious pulse.
First try with the adaptor disconnected, to make sure the miss fire isn't something else.
If it proves to be the adaptor, I'd mount it as close to the rev-counter as possible (so well away from MS and its wiring) and derive the +12v from the rev counter +12v.
Where is the tach adaptor mounted? It produces a pretty vicious pulse.
First try with the adaptor disconnected, to make sure the miss fire isn't something else.
If it proves to be the adaptor, I'd mount it as close to the rev-counter as possible (so well away from MS and its wiring) and derive the +12v from the rev counter +12v.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
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Can't find a, "lost sync reason," field anywhere ?
I have disconnected the ign live from the main relay, and wired into the back of the tacho instead. The tach adaptor is sitting at the back of the engine compartment on the top of the heater box, under the front scuttle. I have fixed it there, then shortened all of the wires so it is nice and tidy.
Took it up the road, still misfires, disconnected it, still misfires
Took it for a spin and got the engine nice and warm, around 15 minutes popping around town, and the misfire did get a lot better, so drove around for another 30 minutes, and it's all but gone. I do think it just maybe down to not being driven for a while, so I'll try to get out a bit more and hopefully that will solve it
The tacho still has a little jump now and again, but it's very useable, so many thanks Dave, your help was very much appreciated.
Regards, Richard
I have disconnected the ign live from the main relay, and wired into the back of the tacho instead. The tach adaptor is sitting at the back of the engine compartment on the top of the heater box, under the front scuttle. I have fixed it there, then shortened all of the wires so it is nice and tidy.
Took it up the road, still misfires, disconnected it, still misfires
Took it for a spin and got the engine nice and warm, around 15 minutes popping around town, and the misfire did get a lot better, so drove around for another 30 minutes, and it's all but gone. I do think it just maybe down to not being driven for a while, so I'll try to get out a bit more and hopefully that will solve it
The tacho still has a little jump now and again, but it's very useable, so many thanks Dave, your help was very much appreciated.
Regards, Richard
Does the tach kicking co-inside with a misfire? Just that I had it running up to 8000 rpm here and it was stable.
If you want to play, you could try it from IDM on EDIS again - that's what's driving mine. One less stage of reading pulses.
As regards the misfire, there is a tendency to think EDIS bomb proof - which it generally is. But a mate had a coil fail such that it drove one plug of a pair OK but not the other. And are you using resistor plugs?
If you want to play, you could try it from IDM on EDIS again - that's what's driving mine. One less stage of reading pulses.
As regards the misfire, there is a tendency to think EDIS bomb proof - which it generally is. But a mate had a coil fail such that it drove one plug of a pair OK but not the other. And are you using resistor plugs?
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
-
- Getting There
- Posts: 238
- Joined: Sat Feb 14, 2009 11:04 pm
- Location: Yorkshire
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- Getting There
- Posts: 238
- Joined: Sat Feb 14, 2009 11:04 pm
- Location: Yorkshire
Finally got a few minutes to finish this off
Tidied everything up, replaced the front scuttle, put the wipers back (been doing some work getting them to work better), started him up and went for a spin.
He used to just tear up hills from low revs, but when the misfire arrived, this was the worst place, up hill in low revs. Any hard acceleration started the misfire, but from low revs on an incline was not good at all.
Got to a hill, and eased my foot down to accelerate up it, from 1,800 rpm. He took off like a scalded cat, so problem solved
I did have the power to the tach fix coming from the main relay in the MS, so I suppose that's what caused it - who knows, he may have been having a bad day.
Tacho is working ok now, little jump now and then, but to be quite honest, it hasn't worked for so long now, I really can't remember if it did that before
Thanks for all your help, especially Dave
Tidied everything up, replaced the front scuttle, put the wipers back (been doing some work getting them to work better), started him up and went for a spin.
He used to just tear up hills from low revs, but when the misfire arrived, this was the worst place, up hill in low revs. Any hard acceleration started the misfire, but from low revs on an incline was not good at all.
Got to a hill, and eased my foot down to accelerate up it, from 1,800 rpm. He took off like a scalded cat, so problem solved
I did have the power to the tach fix coming from the main relay in the MS, so I suppose that's what caused it - who knows, he may have been having a bad day.
Tacho is working ok now, little jump now and then, but to be quite honest, it hasn't worked for so long now, I really can't remember if it did that before
Thanks for all your help, especially Dave
Rover P6 4L V8
Megasquirt MS1 EDIS
5 Speed
Megasquirt MS1 EDIS
5 Speed