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poor tach signal ford tfi

Posted: Sat May 27, 2006 8:33 am
by feldz82
I'm curently running a msII v.3 on my 351w with tfi. I have a problem with the tach signal. I'm not getting a consistent signal. I was alble to get the car started, but after sitting a while, I don't get a signal, then It comes back. Am I missing something? also in megatune, I'm supposed to set the ignition to trigger rise in the ignition settings but I don't have that option. I've been setting it to trigger return. how do I add trigger rise?

Posted: Tue May 30, 2006 2:51 pm
by Bernard Fife
I'm supposed to set the ignition to trigger rise in the ignition settings but I don't have that option. I've been setting it to trigger return. how do I add trigger rise?
feldz82,

You either need to upgrade your code or your MegaTune version (likely both). You don't tell us what you are currently running, so it's hard to say for sure, though.

Lance.

Re: poor tach signal ford tfi

Posted: Tue May 30, 2006 7:01 pm
by MegaScott
feldz82 wrote:I'm curently running a msII v.3 on my 351w with tfi. I have a problem with the tach signal. I'm not getting a consistent signal. I was alble to get the car started, but after sitting a while, I don't get a signal, then It comes back. Am I missing something? also in megatune, I'm supposed to set the ignition to trigger rise in the ignition settings but I don't have that option. I've been setting it to trigger return. how do I add trigger rise?
Can you post the changes you did to the Tach in circuit to support TFI?

Also, please post your configuration list, and .msq.

Thank you!!

Posted: Wed May 31, 2006 7:48 am
by feldz82
I did the mods stated on the diyautotune site on how to megasquirt your mustang: hall optical circuit, 1k 1/4 w resister in d2, jumper xg1 to xg2, optoin to tachselect, tsel to optoout, I installed the high current ignition driver circuit, Installed r43, and put a 100ohm 1/4 w resistor on the ign/igbout jumper and s12. I changed the code to the 2.3 code and set the ignition settings to 10* trigger offset, falling edge, trigger rise, standard coil charging, going high inverted and set the dwell to 1.0 milliseconds. the car starts when I have a signal then the signal is gone. I have a msd 6a laying around, could that solve anything or is it the megasquirt?

Posted: Wed May 31, 2006 3:23 pm
by MegaScott
feldz82 wrote:I did the mods stated on the diyautotune site on how to megasquirt your mustang: hall optical circuit, 1k 1/4 w resister in d2, jumper xg1 to xg2, optoin to tachselect, tsel to optoout, I installed the high current ignition driver circuit, Installed r43, and put a 100ohm 1/4 w resistor on the ign/igbout jumper and s12. I changed the code to the 2.3 code and set the ignition settings to 10* trigger offset, falling edge, trigger rise, standard coil charging, going high inverted and set the dwell to 1.0 milliseconds. the car starts when I have a signal then the signal is gone. I have a msd 6a laying around, could that solve anything or is it the megasquirt?
Also you should jumper D1.

Set the Dwell to at 8ms, that's a typo in the Manual, it should not be 1ms.

The trigger offset should be 0 unless your Megasquirt advance value and the actual advance value.

The MSD could fire your coil instead of the TFI module, but does nothing for your input RPM dropouts. Once you get the PIP working properly you won't need an MSD.

Posted: Thu Jun 01, 2006 8:06 am
by feldz82
nothing still. I don't know what else to do. I've been working on this for 6 weeks now and I'm about ready to throw in the towel. if it's gonna be this hard to get it started, then it's probably a long way off to driving. thanks for the help though.

Posted: Thu Jun 01, 2006 4:05 pm
by MegaScott
feldz82 wrote:nothing still. I don't know what else to do. I've been working on this for 6 weeks now and I'm about ready to throw in the towel. if it's gonna be this hard to get it started, then it's probably a long way off to driving. thanks for the help though.
I still don't understand totally what the exact problem is. You try to start it and it trys to start, then turns off? Or you never get RPM?

Can you verify that you used a 1k resistor in place of D2? and that you have D1 jumpered.

Do you have a stim you can use to test the Megasquirt off the car?

What was the method you used to wire it up? Do you have a harness directly wired to the Sensors, or are you splicing into the stock harness?

Did you make up a diagram of all your connections? Can you post a list of your connections?

What version of MS2 Firmware are you using? Megatune version?

Can you post a datslog of what the car does when you crank it?

Can you post an .msq of your Megatune configuration?

There's still a lot of things you can do, The TFI setup is probably the easiest way to hookup a Megasquirt there is. Usually if it doesn't work it's because of a bad connection, a short, or a miswire, If you checked for all these things and everything else is by the book, there's no reason you should not have an PIP signal. Sometimes all it takes is a second set of eyes to check your setup.

Posted: Thu Jun 01, 2006 4:54 pm
by feldz82
when i turn the motor over, I get no tach signal. There were times i did get a tach signal and the car fired and ran. but after a while the tach signal is gone. It's inconsistant, I haven't been able to get a tach signal the past two days. I did put a 1k ohm resistor in d2 and jumpered d1. I also tried to jumper r43 after reading up on the tfi trouble shooting in the forums. I have a stim and eveything seams to be working. I spliced into the factory wiring harness at first and experienced the same problem, so I made a harness according to the msII v3 wiring shceme. I wired the ignition according to the diy site remote mount tfi diagram. I used my own relays. I'm using the v2.33 embedded code and megatune 2.25. I tried setting the trigger offset to 0 and the dwell to 8.0. how do i post a datalog and msq? I'm pretty new at this. I'm thinking of changing the ignition module, maybe it's bad, but It work fine before and has low miles. I don't know if this has anything to do with the ignition but my fuel pump circuit isn't responding either. thanks

Posted: Thu Jun 01, 2006 5:10 pm
by Bernard Fife
feldz82,

There are some methods to improve the triggering with the Hall input circuit for those that have troubles in this document:

http://www.megamanual.com/ms2/inputHEI.htm

Lance.

Posted: Fri Jun 02, 2006 7:49 am
by MegaScott
feldz82 wrote:how do I load the MSnS E code into msII?
MSnS-E does not work on MSII, you need the old MS1 CPU for that. If your MS2 CPU does not trigger on PIP now, what makes you think the older CPU with different firmware will make a difference? I regularly change from MS1 to MS2 and if it won't work for one, it won't work for the other, unless you have some kind of weird firmware corruption or a faulty processor.

Replacing your TFI module will help if you have a bad one, or you could have a bad Hall effect module.

The other option is either build or borrow a stim, or send your ECU back to be tested.