# tach and fuel pump help (r1 carbs)



## rysskii3 (Apr 19, 2006)

*Edit: MSD 8920 tach adapter solved the problem. 
* 
thanx for everyone's help. 


2l 16v CE2 wiring 
Need help with getting the tach and fuel pump to work. 
i hooked up the tach adapter 8910 to white from ignition box, the same white wire that goes to yellow on start/retard. the red from tach adapter is hooked up to the red on Ignition/start retard/ pin 4 on ICM. the white wire from the adapter should also be connected to the tach directly? if so where? i have all the stock wiring removed, even the stock red/black wire that sat on negative ignition coil (tach wire). by looking at the stock wiring diagrams, the red/black wire goes from the negative ignition wire, to 6 pin gray plug at location number 2, the wire that comes out is green, and that goes to fuse box location f/9. 
























I only pulled the wires out of 3 connectors in the fuse box, they are in order F, G1,G2. the wires were originally connected to the 2 6 pin plugs attached to the ecu (T6a and T6b)


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## ps2375 (Aug 13, 2003)

Have you tried the Tach Output from the MSD, I know it will drive the tach on an 80 Scirocco just fine, and it might be enough of a signal to supply to the FP relay.


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> Have you tried the Tach Output from the MSD, I know it will drive the tach on an 80 Scirocco just fine, and it might be enough of a signal to supply to the FP relay.


 nope, didnt even bother with that since MSD people told me not to. 
where in the fuse box should i plug the wire from the tach adapter? f/09?


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## ps2375 (Aug 13, 2003)

What are "MSD people"?


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> What are "MSD people"?


 the peoples that work for MSD, in Texas.


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## ps2375 (Aug 13, 2003)

Well, that makes no sense, did they give a reason? I'd try it anyway.


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> Well, that makes no sense, did they give a reason? I'd try it anyway.


 they said the signal strength or something along those line. i will try to directly plugging it to the 6a tach signal output then. should the wire lead to f/09 spot in the fuse box?


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## ps2375 (Aug 13, 2003)

Not sure, ours ours had no fusebox. But if that is were the stock one comes in, sure.


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> Not sure, ass ours had no fusebox. But if that is were the stock one comes in, sure.


 Thanx


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## rysskii3 (Apr 19, 2006)

rysskii3 said:


> Thanx


 tried using the tach output on the ignition box, no luck. i did notice that the tach adapter was getting pretty warm. also, i forgot to mention that i am using an 89 helios 8k cluster. i cant seem to find which wire is for the tach, is it still the u1/06 on the fuse box?


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## ps2375 (Aug 13, 2003)

I don't think you need the adapter with the "tach output" terminal.


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> I don't think you need the adapter with the "tach output" terminal.


 i tried only using that, not working. fuel pump works fine if i use the horn relay (turns on with the key and turns off when the key is removed)


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## ps2375 (Aug 13, 2003)

well, for that dash, I don't know what you need. Have you tried the original wire from the coil to the fuse panel, even with the MSD running it? I know that the tach won't read correctly, but that would allow the relay to work properly, then all you have to do is find the correct input wire for the dash and run that directly to the MSD tach output.


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> well, for that dash, I don't know what you need. Have you tried the original wire from the coil to the fuse panel, even with the MSD running it? I know that the tach won't read correctly, but that would allow the relay to work properly, then all you have to do is find the correct input wire for the dash and run that directly to the MSD tach output.


 tried a bunch of different things. i think my problem is that i have an 8k helios gauge in my car, i cant find which wire is the tach wire. the bentley says that in 90-92 gti (the wiring i have), u1/06 green wire is the tach, but when i run the tach wire to it from coil, from msd, from adapter, nothing makes a difference.


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## ps2375 (Aug 13, 2003)

I would get the car running off of the stock relay first, then work on getting the tach working. Does the rest of the cluster work? Have you tried an original cluster?


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> I would get the car running off of the stock relay first, then work on getting the tach working. Does the rest of the cluster work? Have you tried an original cluster?


 Pump works, so that's done. The rest of the cluster seems to be working, at least temp does and the lights come on. I will not use the stock cluster, so there is no point in trying that.


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## ps2375 (Aug 13, 2003)

I didn't say to use the stock cluster, I asked if you have tried the stock cluster to see if the tach works with the config you have. And then you can compare the two clusters to see if they are wired the same to be able to get the other cluster's tach to work. 

And the FP(horn) relay working off the IGN sw and not having an rpm signal to enable the "safety" shutoff is kind of asking for something bad to happen. Not saying it will, but it could.


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> I didn't say to use the stock cluster, I asked if you have tried the stock cluster to see if the tach works with the config you have. And then you can compare the two clusters to see if they are wired the same to be able to get the other cluster's tach to work.
> 
> And the FP(horn) relay working off the IGN sw and not having an rpm signal to enable the "safety" shutoff is kind of asking for something bad to happen. Not saying it will, but it could.


 Don't have a stock cluster, and as far as I remember, the wiring was different because the rpm gauge wasn't working, so I had to get another wiring harness from a car with MFA.


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## ps2375 (Aug 13, 2003)

Seems you are mixing and matching one too many things. I would make the system as basic as possible and go one by one to get them working. I don't know if you need a working MFA, as you are mounting carbs, I don't see this car being a "street legal" car in CA. for much more of it's life. Seems you need to get a wiring diagram for what ever this cluster came out of and compare that to what you have in the car for wiring now.


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> Seems you are mixing and matching one too many things. I would make the system as basic as possible and go one by one to get them working. I don't know if you need a working MFA, as you are mounting carbs, I don't see this car being a "street legal" car in CA. for much more of it's life. Seems you need to get a wiring diagram for what ever this cluster came out of and compare that to what you have in the car for wiring now.


 Car is for racing only, with maybe some city driving. I might actually have the regular ce2 cluster, so I'm gonna start digging through the garage.


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## rysskii3 (Apr 19, 2006)

Hooked up the original gauge cluster and original wiring harness, no luck.


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## ps2375 (Aug 13, 2003)

Well, it used to work, correct? Find the wire that drives the tach from the coil, or use the MSD tach output and get a tach reading, then compare the wiring to the other cluster.


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## rysskii3 (Apr 19, 2006)

ps2375 said:


> Well, it used to work, correct? Find the wire that drives the tach from the coil, or use the MSD tach output and get a tach reading, then compare the wiring to the other cluster.


 did that, no go. the red/black wire that is connected to the negative on the ignition coil went to pin 2 on the gray connector pictured above, and then im pretty sure it went to f09, which is internally connected to u1/06 the tach. i am missing something with the wiring, just not sure what.


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## rysskii3 (Apr 19, 2006)

I have been researching this issue all weekend and came up with interesting information. Is it possible that the 8910 box not sending enough voltage to the tach since it used to be hooked up to the negative terminal on the coil. I found a few threads that mentioned to use the 8920 tach adapter box because it sends a stronger signal to the tach. 
i also called MSD again, now they are telling me that the 8910 was not the right adapter, i need the 8920. when i called them a few weeks ago, i was told that i need the 8910. WTF MSD.:banghead:


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