Missfire issues and more

[spoolin ddub]

Here is the situation. Soon as I start to boost my car misfires. I thought it was the coils. What puzzles me is that is clears up at higher rpms after 3800rpm. The idle goes crazy and the logs show that at 7K the rpms jump up to 10800rpm automatically hits the rev limiter and then goes back down. The clutch is not slipping and the digital rpm tach shows a constant climb in rpm with no spike. I'm 98% sure my CAS is going bad but would a bad CAS cause the misses when I come on to boost as well? Or would that be a problem with the ignition? The shit is ####ing crazy and frustrating. I'll take a vid of a 35psi pull and post it.

 

[gofer]

This could be a few things but your car looks stock according to your profile so helping you is damn near impossible. There are a few things it can be but knowing whats on your car is a must, especially the tuning software. Instead of a video you can post a log if your using dsmlink since it could be tuning related.

Update your profile.

 

[spoolin ddub]

This could be a few things but your car looks stock according to your profile so helping you is damn near impossible. There are a few things it can be but knowing whats on your car is a must, especially the tuning software. Instead of a video you can post a log if your using dsmlink since it could be tuning related.

Update your profile.

Profile updated. It's definitely not a tuning issue. I did a few pulls with Mike Reichen and we both looked at the logs and A/F ratio, voltage etc is on point. It is definitely a sensor/electrical issue.

 

[gofer]

Thanks for updating your profile however, I see you own 2 DSM's so is it the '90 or the '97 which changes things. I'm assuming its the '90 since in your OP your talking about the tach jumping to 10k but if its the 2g let me know...

The '90 gets its RPM signal from a tach interface module, unlike the '91-'99 DSM's who have it built into the power transistor. The tacho's casing must be grounded for it to work correctly, its also wired into the coil at pin 3 and the ECU pin 109. Its attached to the back of the IM near the throttle cable and this is what it looks like...

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