big-phil Posted January 28, 2007 Share Posted January 28, 2007 When I first hooked MSnS up I did not invert the coil signal, and the vb921 got REAL hot several times. Well the other day the car died all of the sudden, then came back on. In megatune you can see that the coil is not getting a signal when this happens, then it came back and Chris (the tunner of the car) drove the dog $h!t out of it, and could not reproduce the problem. I then cleaned up the wiring going to the relay box, and used di-electric grease everywhere. That was last week, before my latest video. Then today on the way home from work it dies about 3 times on the highway then comes back after about 10sec. I just rechecked all the wiring from the relay box to everything. It all has power where needed. and all wires from the relay box to their perspective destination have good readings and show no breaks. This makes me think the vb921 is going out. This had me worried, untill I just orderd one from DIYautotune.com for $5.95. Is there a way to test the vb921?? So I can be sure its out. I searched and came up with nothing. Thanks all!!!!!!!!!!!!!!!!!!! Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted January 29, 2007 Share Posted January 29, 2007 The later Stims with the IGN LED light provide some measure of testing a VB921. However, trying to track down intermittant operation in one is a real nightmare. I can't think of any trick that does not involve an oscillascope at the very least. Quote Link to comment Share on other sites More sharing options...
z-ya Posted January 31, 2007 Share Posted January 31, 2007 What is your dwell set to, and what coil are you using? If you suspect the VB921, for $5.95 just replace it. An improper dwell over long periods of time can make one fail. Or, the damage could of been done when you had the output not inverted. The device could now be just starting to fail because of damage that was done earlier. Put a new one in so you know what you are working with. Quote Link to comment Share on other sites More sharing options...
big-phil Posted January 31, 2007 Author Share Posted January 31, 2007 What is your dwell set to, and what coil are you using? If you suspect the VB921, for $5.95 just replace it. An improper dwell over long periods of time can make one fail. Or, the damage could of been done when you had the output not inverted. The device could now be just starting to fail because of damage that was done earlier. Put a new one in so you know what you are working with. I think the dwell is 6.5, 1.5, and .5 If that does not sound right I can fire up the lap-top and tell you for sure. Quote Link to comment Share on other sites More sharing options...
Gavin Posted January 31, 2007 Share Posted January 31, 2007 Doesnt sound right to me. My max dwell is only 2.6. - But than I see you have a much different coil than mine... Quote Link to comment Share on other sites More sharing options...
big-phil Posted February 3, 2007 Author Share Posted February 3, 2007 I have an Accell super coil, any help with dwell settings would help. I FOUND THE PROBLEM. It was the optical sensor inside the dizzy. I put the guts from a z31 into my 83 turbo dizzy. Sort of an upgrade I guess? And that fixxed it! Quote Link to comment Share on other sites More sharing options...
z-ya Posted February 3, 2007 Share Posted February 3, 2007 I wouldn't exceed 3mS dwell unless you have put a scope on the coil output. A dwell of 6.5 seems high. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.