ch3vyb1gbl0ck

Hey guys hopefully u can help me! I have a 6 speed 94 lt1 camaro I've owned the car for about 6 months now. the guy who owned the car before me replaced the short block with a 95 lt1 engine that's .030 over with the optispark 2. The engine has other upgrades including cam, 1.5 ratio valve rockers, cai and catback exhaust. The issue I'm having is I would drive the car for up to half an hour, let it sit while off for about an hour, and when I go to start it again it either won't start or it will start but stall shortly after. I checked spark coming from the coil and wasn't getting a spark under no start condition. Therefore I replaced the coil and icm but was still getting the same issue. My shop owner says it can't be the opti because I'm not getting spark out of the coil. Has anyone else had similar issues? Please help!!!

Injuneer

The Opti has two parts. 1) high voltage - but requires spark from the coil. 2) cam position sensor - PCM needs the cam position to fire the ICM to fire the coil. So, yes, it can be the Opti. If it is a problem with the optical cam position sensor, it will set a code that does not turn on the SES light. Have you scanned it for codes? You either need a simple OBD-1 scanner, like AutoXray used to make, a GM Tech 1 or 2, or scanning software.

Download of free 93-95 scanning software - not only pulls codes, but can show you real time data and run a data log of the PCM showing sensor readings and calculated parameters. You buy the cable. Recommend a ready-made cable, since the Chines components to build your own have really gone down hill.

https://www.camaroz28.com/forums/com...95-lt1-874306/

No impact of the Opti 2 on the process... that just means the drive mechanism is off the cam dowel pin, rather than a splined shaft, and the case is vented.

Has the PCM been tuned for the cam? FYI, stock rocker ratio is 1.5X.

ch3vyb1gbl0ck

It has been tuned with one of those hand held programmers that you plug Into the obd1 I also failed to mention it ran perfectly fine before it started stalling

ch3vyb1gbl0ck

Also there's no check engine light but I scanned it anyways but found no codes I was using a snap on solus pro scanner

GaryDoug

I don't think the Solus Pro supports any OBD1 cars. At least, I find no mention of anything but OBD2 in the user manual. If your car has an OBD2-style connector, it is actually OBD1. (edit)

https://www1.snapon.com/Files/Diagno..._ZEESC316C.pdf

Injuneer

I've seen online discussions that indicate the Solus OBD-1 is not reliable on the GM "transition" years, but I've had no experience with them. We know Scan9495 works perfectly.

OP - Check the first few posts in the "sticky" at the top of this forum: "Diagnosing a Bad Opti"

Note the links to Shoebox's site.

ch3vyb1gbl0ck

thanks guys for the help!! found a code using a different scan tool and just ordered a new opti, so should be back on the road in no time. i got a chandler opti which is one of the cheaper optis, even though everyone says to go oem. it includes a lifetime warranty though and only cost 140 so hopefully it lasts but if it doesnt i just gotta tear it all apart again. also next time i will look for similar posts.

Injuneer

The Chandler has a high failure rate..... good luck.

Injuneer

You might also want to check the adequacy of the tune. The only "hand held" I've ever seen for the OBD-1 LT1 is the Hypertech, and that has a single "canned" program that is for stock engines, and has actually been show to lose HP, unless combined with the Hypertech 160degF thermostat, and revised fan on/off temps. The OBD-2 Hypertech did accommodate a cartridge, and that cartridge could be swapped for a scan cartridge, or a custom tune cartridge (written by Hypertech) for modified engines. But the OBD-1 version could not do that.

Not Dave

Can't stress enough on the use of Delco or Delphi opti's and nothing else. They have the best reputation.

That being said I hope the opti replacement is what is needed and when you do it the problem goes away.

ch3vyb1gbl0ck

I should be getting the Chandler unit I, a week and I'll be replacing it the following weekend I will let you guys know if that fixes my problem. thanks
for the help

Injuneer

Suggestion for all Opti's, no matter who made them - loc-tite the rotor screws.