Tach spikes under load/RPM
Moderators: jsmcortina, muythaibxr
Tach spikes under load/RPM
Using stock CAS. V3 29q2
The car idles very well, and under very light loads and low rpm, it is fine. But when any load is put on the engine, the car stutters violently and I tracked this down to a tach spike using datalogs.
The car ran very well on fuel only, is there some type of interference
I should fix or resistors that I could add?
Thanks!
In neutral, it revs freely to about 3000-4000rpm, when it starts missing and the tach becomes unstable.
The car idles very well, and under very light loads and low rpm, it is fine. But when any load is put on the engine, the car stutters violently and I tracked this down to a tach spike using datalogs.
The car ran very well on fuel only, is there some type of interference
I should fix or resistors that I could add?
Thanks!
In neutral, it revs freely to about 3000-4000rpm, when it starts missing and the tach becomes unstable.
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- MS/Extra Newbie
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I have a similar problem. I have added some resistance to the VR negative cable on the board ( input of the LM1815) and the misfire climbed to around 7000 rpm, but still there. I have the maps by TPS (Alpha N), but i don't think that was the problem.
I guess the motor have a poor ground, because it is a drag car and have a lot of work to do yet. I will make some test later.
Code: 26h4 - TPS - 4 ITB - 1.600 cc - Racing Cam
Thanks
I guess the motor have a poor ground, because it is a drag car and have a lot of work to do yet. I will make some test later.
Code: 26h4 - TPS - 4 ITB - 1.600 cc - Racing Cam
Thanks
Mikymar
Fiat 1.6L Turbo @ 30 psi - MSnS Extra whit CDI
soon Ford 2.5L Turbo
Fiat 1.6L Turbo @ 30 psi - MSnS Extra whit CDI
soon Ford 2.5L Turbo
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- MS/Extra Newbie
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- Joined: Tue Mar 14, 2006 6:52 pm
- Contact:
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- MS/Extra Newbie
- Posts: 11
- Joined: Wed Mar 16, 2005 2:29 pm
Wenn you have an noissy tach signal you must ground externally the input ground of U4 to insolate the noise tach input.
I have no problem with noise, but always is a god practice insolate cables with sync signals.
I use a 36-1 wheel and LM1815....but have no scoped a noissy signal at all.
I have fried the starter motor, when the motor run again i will made some test with the coils and the VB921 ground directly grounded to the negative terminal of the batery.
I hope ground connection is the problem.
I will post the result of the test soon as possible.
I have no problem with noise, but always is a god practice insolate cables with sync signals.
I use a 36-1 wheel and LM1815....but have no scoped a noissy signal at all.
I have fried the starter motor, when the motor run again i will made some test with the coils and the VB921 ground directly grounded to the negative terminal of the batery.
I hope ground connection is the problem.
I will post the result of the test soon as possible.
Mikymar
Fiat 1.6L Turbo @ 30 psi - MSnS Extra whit CDI
soon Ford 2.5L Turbo
Fiat 1.6L Turbo @ 30 psi - MSnS Extra whit CDI
soon Ford 2.5L Turbo