MissLindsey

I have a 1995 Trans Am LT1, supercharged, new motor, etc. So about a month ago I finally got this thing running good and then all the sudden it started dying at high RPM's (completely dying- try to get on the highway, would die as soon as it got over 3500 RPM). It wouldnt start the next time I tried to start it, but then I did get it to start once or twice. (It would always crank, just never fire) I figured it was ANOTHER opti, I had the jegs one for about 1000 miles, so I put in a GM one from Summit. However, the thing still wont run. It started for about 10 seconds, sounded like crap, (dad/mechanic thought it sounded like the timing was advanced) and then it died and has not again restarted. Is my new opti bad? I have had that happen before. I also read some other posts where a fuel pump could cause this. Thanks for all the help.

old93camaro

iTrader: (8)

Sounds like your coil or icm check both and go play with it again

gregrob

iTrader: (8)

No it doesn't... don't listen to that ^

Your Dad could be correct, it is very possible to insert the opti the wrong way and severely advance the timing, make sure that's not the case.

airfix

iTrader: (30)

Whats greg said, I'd be looking into if the opti was installed correctly (the cam dowel is in the right spot on the opti). From what you mentioned it sounds like the new opti was installed in the wrong position. And if you want to make sure the fuel pump is good throw on a fuel pressure gauge and see what kind off pressure you get.

Enforcerws6

iTrader: (1)

i vote coil or module SINCE originally it was breaking up and dieing at high rpm where a coil shows its weakness the most if its still trying to spark.
but i would for sure check the fuel pressure as well as it could make it die at high rpm as well

RamAir95TA

iTrader: (2)

If the optispark is installed incorrectly it is highly unlikely it will run at all.

95BlkBird

Mine would die over 3k also and I just replaced Opti. Eventually it went out completely and wouldnt restart. Coil and ICM later she runs great. I missed the cam dowl on my 1st Opti install and it ran fine for a min then it managed to move and sounded exactly like it had jumped time. Once it moved though it wouldnt run for ****.

idformula

I thought either the opti was on or it was 180 off?

BigD383lt1

shbox.com has a good view of the opti and where it should be at tdc for each piston... I would first pull the coil and check that. I believe Autozone can test it if not here is a link to with the specs to test it yourself. The other thing to give a quick check to is fuses for the injectors. I had one blow for what ever reason and it felt like the cam was 180 out. Car would start sometimes but would not stay started of coarse it was only running on 4 cyl.

http://shbox.com/1/coil_testing.jpg
http://shbox.com/1/4th_gen_tech2.html#opti_test

LT1

iTrader: (1)

Have you been able to check any of the things that's been mentioned.

-opti installed correctly
-coil test
-fuel pressure test
-ICM
-spark plug wires in correct order

gregrob

iTrader: (8)

Not true at all. Seen it on two different cars, one being my own.

mark97ta

iTrader: (1)

IT WILL RUN INSTALLED WRONG... very very poorly though

RamAir95TA

iTrader: (2)

Perhaps on the spline drive, but if the pin is inserted into the wrong hole on the pin drive opti, the timing would be off 120-degrees.

CumminsPower

Mine did the exact same thing last week. I was driving and when it got around 3000 the car would shut off. Then after starting it a few times it stopped firing. I had a new opti, Coil, ICM, wires, etc put in. I just had BBR redo basically everything. It fixed the problem and I'm going to pick it up today.

whytryz28

iTrader: (28)

The splined drived wont install, there is 1/2" gap between the opti plate and the timing cover if the notch isn't lined up correctly.

If someone torqued it down even after seeing that, then they are stupid.

BigD383lt1

not a completely true statement at all... if they have a aftermarket cam most of them are made for different years and the pin is different between the vented and non vented opti. So may have to cut the pin if your running a non vented opti.

gregrob

iTrader: (8)

It will still run, terribly.



Not true either, I've done it

RamAir95TA

iTrader: (2)

I don't see how it will run. If the coil fires and the rotor is 120-degrees away from the terminal on the cap on every cylinder, where is the spark going to go? If you turn a conventional distributor 120-degrees, will it run? No.

whytryz28

iTrader: (28)

How can you install it wrong? Ive replace mine many times and it will either seat all the way or it will leave a big gap. What brand Opti? I've used Delco only.

IronOutlaw

iTrader: (4)

My Chandler opti will go in correctly or 180* off into my hotcam. My old summit opti will only slide in one way. I think the splines are slightly different on the Chandler unit.