MSII V3 blowing fuses under boost only

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VG30ET
MegaSquirt Newbie
Posts: 3
Joined: Sun Apr 18, 2010 10:47 am

MSII V3 blowing fuses under boost only

Post by VG30ET »

Hello,

I have an MSII V3 installed on a 87 300ZX turbo. I have a very rare problem - I have a standard wiring setup and when I go under boost (about 5 psi) I am blowing the 2A fuse for the MS, and the two 5A fuses for the injectors. It seems like this problem only happens under boost. If I drive around slowly I don't see the issue.

During install/intial setup I discovered that I had a short on one of my injector pigtails and blew C16. I replaced and fixed the short and everything seems fine except when I step on the gas.

Could anything else be going bad? If I put the MS on the stim and try to replicate the conditions (except for the map value) everything seems ok.

Any help is appreciated.
Matt Cramer
Super Squirter
Posts: 2951
Joined: Sat Jul 03, 2004 11:35 am

Re: MSII V3 blowing fuses under boost only

Post by Matt Cramer »

What is the resistance on your injectors?
VG30ET
MegaSquirt Newbie
Posts: 3
Joined: Sun Apr 18, 2010 10:47 am

Re: MSII V3 blowing fuses under boost only

Post by VG30ET »

I figured it out - I had the PWM set to 30% for low impedence injectors (mine read 2.4 ohms) - lowered it to about 15% following the procedure and it appears to be working well.
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