LTCC install ?
Followed the instructions and fired the car, it seem to run fine for like 15 seconds then backfired threw the intake and died. Nice!
So I checked and re-checked all the connections and they seem to be fine.
I am going to pull the opti back off and make sure that silly needle in a hay stack gm designed is in the slot properly...for those that are not familiar with a vented opti it has a nipple that comes off the cam and slides into the back of the opti.
What's is weird is I don’t have any indicator lights on at all on the ltcc module itself? It has red and green indicator lights on it and nothing is lit-up?
So Sunday I am going to pull the opti back off and make sure it is on correctly but wanted to start a post on this incase others are interested in this and also to see if anyone that has already installed the ltcc has any suggestions?
I e-mailed bob and we will see what he thinks?
When everything is wired and ready to go you should see a power-on blink from the led's, at least one of them.
The green led lights up when valid opti pulses are recieved (engine turning)
Afterbeing away for a couple of years I am going to get my car website back online and this will definately be on the mod page with instructions and pics.
I am a computer engineer and if I am having issues with this I think the average joe could benefit from a detailed ltcc mod page.
As most of us with the vented opti know its like threading a needle.
Anyway the car is actually running now but not that great.
I am now getting 3 red blinks on the ltcc red led.
instructions say "wrong # of hi-res pulses counted diring a high low-res pulse or low low-res pulse" ? greek to me and i am greek

I sent bob an e-mail but any help would be appreciated.
got a new reman opti and that didnt help, so i went back and got another opti and that one didnt work.
I know they are reman's but you would think the opti sensor would be good on atleast one of them?
So I am waiting to hear back from bob and will probably end up ordering a new opti from gm.
This sucks!
checked fuses and they are fine, i put in a 25a just for the heck of it
checked fuel pressure and its 41psi, that should be ok
checked for spark and it shocked me...didn't feel good so i would say we have spark
got a solid green on your ltcc when cranking
after ~20 seconds or so get 2 red blinks, repeatedly
opti is on correctly
ltcc seems to not be firing the coils at the correct time, backfiring threw intake. so coil is firing when valve is open.
I seems like the ltcc box is not translating the timing correctly to fire the coils at the correct time.
verified 12v key on for the ltcc 2 pink wires to my pink wire (95 is pink)
verified 1.8v burst from the opti when cranking (white wire) so it seems to be sending the signal.
can anyone think of anything else i can check?
Thanks!
if the pigtail dont work i guess im gonna get a gm opti from summit next?
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It's not like the older ltcc that had a wire to each coil, it now uses the stock coil harness from an lsx and the ltcc harness just plugs into it.
After troubleshooting everything, new plugs, wires, coils, 02 sensors, grounds, I'm still having the same problem.
My car will idle ok, but everynow and then, it will backfire through the intake, like it's firing too early, then it will die. It will drive, just not very well!
I'm getting no CEL's, and the box is working, according to the diagnostics.
My mechanic, who I finally took it to, thinks either all the coils are firing, or some of them are firing randomly, early.
He thinks either the box is bad, or the LTCC won't work with aggressive cams.
I e-mailed Bob yesterday, and am awaiting more discussions with him.
It seems to me, that I'm going to have to swap boxes, anyway you look at it, to rule it out.
The motor runs great, when it runs. It has put my full weight Impala into the elevens.
LMK if you find out anything. I've tried everything but going into the opti again, and I don't really think that's where the problem is.
my opti harness just came in and that didnt help, my new gm opti should be here monday from sumitt and my attitude will change sharply with bob if that dont work. he hasnt been much help!
I am a computer engineer and have asked for a schematic and values associated and have not recieved anything but basic diagnostics that i did the 1st week i got this thing.
My coils are mounted under the cowl, like the kit thunder racing sells for relocating the coils and ran the grounds back to the fuel rail's but i will try running a wire to ground over by the battery.
I have lt4 valve covers so i cant ground them to the cover's, they are like a composite plastic.
I think either the box is bad, or it could be possible that I stuck the opti in the wrong hole, and it's out of time. But, I've done opti installs over a dozen times, at least.
Very frustrating!
I aksed him about big cams, etc and he said he has cars running the ltcc that run 9's in the quarter.
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