blowngta

Duh, did you get your car up and going? Was it the opti? I have not been able to work on the Vette for a few weeks, and was wondering if you resolved yours. I was rereading some of the previous posts and I think some of the persistent "needs tuned" guys forgot that this is a lt4 car. It came stock with 28# injectors. The fist thing I did while tuning was change the injector size accordingly. I have been fighting with the data logger not displaying ( have not spent a lot of time with it yet), but from what I am seeing it appears that all of the timing is frozen. No advance, and is a steady line somewhere around 8 degrees retarded. I need to verify and will post back, but that would explain every symptom.

duh

iTrader: (16)

I got a new opti this last time with the warranty. It definitely isn't a reman. Unfortunately my symptoms persist even now. I'm currently waiting in an ECM after talking with Ion aka Madtuner. He informed me that due to the heat and vibration associated with these cars, the solder inside the ECM/PCM cracks and causes a bunch of issues. That's what he came up with after looking at my catalog and seeing that the vss was jumping around as much as 180 mph while actually traveling 30-40. It was solidified in my mind that night while driving and seeing 255 mph while sitting at a stop light. As soon as I get the "new" ECM in the car I will update you.

duh

iTrader: (16)

Well it's update time for the OP. Turns out my ECM was toast! Not only have all my problems disappeared, I gained a new one, but I know the problem. My speedo is now inop, but I have a spare ECM now to drive my car and have the original redone. Madtuner nailed it on the head for me. Aside from the speedo problem, my car is running as good as new. Now it's time to track test it, but that will have to wait until the 9th since I'm out of town this weekend. OP, I would definitely find a known good ECM and start there.

kerry67

thanks for you posting your info I now believe I have the same problem as you did it make sense I have been racking my brain with this car for 2 weeks . I will try a new ecm

infinitebird

iTrader: (11)

I figured out the ultimate solution to the opti woes...

get an ls1

duh

iTrader: (16)

I've thought really hard about, but now that the car is running, I'm gonna see what this new trans and converter really got me next weekend. From there will decide weather a or not I start collecting parts.

blowngta

Well it is confirmed....bad MSD opti. I finally got it swapped with a no-named auto zone special I had laying around. The Vette now runs perfect. It cured every issue I was having. No tuning issues at all. I now have to deal with MSD. I really don't want to install the new one they send me. I may just stick it on the shelf (LOL). Thank you all for your advice.

Speedy

Wouldn't recommend that no-name (likely Chinese) opti for too long. Get the Delphi or the AC Delco. My Chinese opti lasted about 2000mi before giving me hell.

duh

iTrader: (16)

My AZ special has been fine. As we're the 3 previously most likely. I think there are just a ton if variables in the design and operation of our computer systems.

Puck

iTrader: (17)

Nope, just the LS1 computer .

blowngta

I agree with all of you. I don't plan on leaving this opti on for long, but I figured he can enjoy his car for the rest of the summer and do it again when the weather turns. It is an absolute shame that a $550 MSD won't work, but a used cheapy works great. MSD should be embarrassed!

As far as the LS1 goes...I got nothing. It is deffinately a better system, but LTs are not bad (much cheaper). As long as it goes fast and makes a lot of noise, it's good with me.

Hopefully this post will help someone out with a similar problem in the future. The best advice I can give anyone reading this is...DO NOT BUY A MSD OPTI!