Stranded in a '96
03-19-2018, 09:16 AM
#21
Drifting
Thread Starter
FWIW, I replaced the ICM and coil too. Hate throwing parts at a problem. Almost as much as I hate being stranded. 
It amazes me that the Corvette isn't sitting on the curb with a for sale sign. I normally have zero tolerance for cars that leave me walking without warning.
I must really like this car.
It amazes me that the Corvette isn't sitting on the curb with a for sale sign. I normally have zero tolerance for cars that leave me walking without warning.
I must really like this car.
03-19-2018, 10:42 AM
#22
Team Owner
Pro Mechanic
1st was the OEM one...it started with a low RPM/high load intermittent 1 cal miss. Then it started breaking up at high RPM, only when hot. With time, the "high RPM" ceiling got lower, only when hot. Finally, it would die when hot, restart and run fine when cooled some. There was a "hard line", right around 210*F where it would work, or not work. Weird.
2nd one failed by simply shutting the car off (w/a corresponding loss of tach signal) while driving down the road. I'd wait 2?, 5? 10" minutes (it varied) and then it would fire right back up run fine and perform fine.
Get the lenses wet/dirty and they are done. (until you clean 'em). They often give warnings....but sometimes they don't.
03-20-2018, 09:15 AM
#24
Drifting
Thread Starter
03-20-2018, 10:21 AM
#26
Race Director
I don't k ow how many miles or years were on your icm and coil, but I don't consider them "throwing parts at it", I would consider them to be preventative maintenance parts. Especially if they're original, but I don't replacing a 10 year old coil as unacceptable.
03-20-2018, 10:45 AM
#27
Drifting
Thread Starter
Guess I should think of them as being much like plugs/wires.
03-20-2018, 02:41 PM
#28
Pro
Icm
I carry a spare ICM . Less than 20 bucks on Amazon or ebay. Less than a minute to switch. You dont have to remove the old one if you get stuck. Just unplug from the old one, plug in the new one. grounding not necessary since ground is supplied in the wiring.
06-10-2018, 08:21 AM
#29
Drifting
Thread Starter
Optispark time? Again?!?
Two hours of pacing, sweating, cringing and riding in a tow truck after a full day at work. Yay.
No warnings. Drive to work was uneventful.
Fires up and instantly dies. Time to get out the noid lights and confirm what I believe will be another exercise in Opti-frustration.
This car requires more mechanic than what lives here. I'm getting too old for this sheet.
It's not a garage queen. More like a jack stand queen.
At least I got one last run on the Tail of the Dragon last month. And thankfully didn't have to tow it from there.
If the noids confirm, My 60 year old hands are going after Utah Tom's two-hour Opti-swap record. If for no other reason than I no longer give a damn. And if that effing balancer doesn't pop off on the first pull, I'll take an air hammer to it.
Then I'm thinking cargurus.com.
Update: As before, fired up this morning, though it struggled at first and almost died. Ambient temp 74F this morning vs. 95F in the parking garage last night. I have a winter driver? Engine heat killed the new ICM already or just defective??
Running very slightly rough at idle.
No warnings. Drive to work was uneventful.
Fires up and instantly dies. Time to get out the noid lights and confirm what I believe will be another exercise in Opti-frustration.
This car requires more mechanic than what lives here. I'm getting too old for this sheet.
It's not a garage queen. More like a jack stand queen.
At least I got one last run on the Tail of the Dragon last month. And thankfully didn't have to tow it from there.
If the noids confirm, My 60 year old hands are going after Utah Tom's two-hour Opti-swap record. If for no other reason than I no longer give a damn. And if that effing balancer doesn't pop off on the first pull, I'll take an air hammer to it.
Then I'm thinking cargurus.com.
Update: As before, fired up this morning, though it struggled at first and almost died. Ambient temp 74F this morning vs. 95F in the parking garage last night. I have a winter driver? Engine heat killed the new ICM already or just defective??
Running very slightly rough at idle.
Last edited by Renfield; 06-10-2018 at 09:13 AM. Reason: Turned the key.
06-10-2018, 11:09 AM
#30
Team Owner
Pro Mechanic
Sorry to hear that, man. That car is definitely challenging you. 
06-10-2018, 01:41 PM
#31
Le Mans Master
Member Since: Oct 2004
Location: South-central Missouri
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Researching Mean Time Between Failure (MTBF) statistical analysis (college course many moonz ago), the two most likely failure periods in a new part's lifetime is immediately after installation and then again after it is (worn out). Furthermore, failure rate over time when the part is initially installed (aka "infant mortality rate") is much worse than after it has reached its lifetime expectancy! (Some would testify to the increase in "infant mortality" of (foreign) manufactured parts, as an example.
)So, it's a given: sometimes there is no practical way to evaluate some parts other than swapping them out. Been there, done that too. But, the issue is after a part is replaced, the saw is; "I replaced (that widget) so that can't be the problem!"
OH, BROTHER! With out verification, HOW WRONG HE CAN BE!? Never assume!(Just sayin!
)
Last edited by Paul Workman; 06-10-2018 at 01:44 PM.
06-10-2018, 02:31 PM
#32
Drifting
Thread Starter
Well... I hear ya, but don't entirely agree without at least attempting to ascertain the performance of the new part.
Researching Mean Time Between Failure (MTBF) statistical analysis (college course many moonz ago), the two most likely failure periods in a new part's lifetime is immediately after installation and then again after it is (worn out). Furthermore, failure rate over time when the part is initially installed (aka "infant mortality rate") is much worse than after it has reached its lifetime expectancy! (Some would testify to the increase in "infant mortality" of (foreign) manufactured parts, as an example.)
So, it's a given: sometimes there is no practical way to evaluate some parts other than swapping them out. Been there, done that too. But, the issue is after a part is replaced, the saw is; "I replaced (that widget) so that can't be the problem!" OH, BROTHER! With out verification, HOW WRONG HE CAN BE!? Never assume!
(Just sayin!)
Researching Mean Time Between Failure (MTBF) statistical analysis (college course many moonz ago), the two most likely failure periods in a new part's lifetime is immediately after installation and then again after it is (worn out). Furthermore, failure rate over time when the part is initially installed (aka "infant mortality rate") is much worse than after it has reached its lifetime expectancy! (Some would testify to the increase in "infant mortality" of (foreign) manufactured parts, as an example.
)So, it's a given: sometimes there is no practical way to evaluate some parts other than swapping them out. Been there, done that too. But, the issue is after a part is replaced, the saw is; "I replaced (that widget) so that can't be the problem!"
OH, BROTHER! With out verification, HOW WRONG HE CAN BE!? Never assume!(Just sayin!
)
06-27-2018, 08:54 AM
#35
Drifting
Thread Starter
I have confirmed that the ICM and Coil I replaced were (and are) good. After the last tow, it again fired up the next morning.
In hindsight, subtle warnings included poor idle (like a small miss), a bit of hesitation, and occasional hard-start.
It's on jack stands in the garage. Just need to find the time to tackle the Optispark removal. Then I'll find out what 2 years and 10K miles looks like on a Petris unit.
If it is the optical component, I have two Mitsubishi originals on stand by.
Meanwhile I've been enjoying the '94 Miata. My little Chevy life jacket.
In hindsight, subtle warnings included poor idle (like a small miss), a bit of hesitation, and occasional hard-start.
It's on jack stands in the garage. Just need to find the time to tackle the Optispark removal. Then I'll find out what 2 years and 10K miles looks like on a Petris unit.
If it is the optical component, I have two Mitsubishi originals on stand by.
Meanwhile I've been enjoying the '94 Miata. My little Chevy life jacket.
06-27-2018, 09:21 AM
#36
Race Director
I have confirmed that the ICM and Coil I replaced were (and are) good. After the last tow, it again fired up the next morning.
In hindsight, subtle warnings included poor idle (like a small miss), a bit of hesitation, and occasional hard-start.
It's on jack stands in the garage. Just need to find the time to tackle the Optispark removal. Then I'll find out what 2 years and 10K miles looks like on a Petris unit.
If it is the optical component, I have two Mitsubishi originals on stand by.
Meanwhile I've been enjoying the '94 Miata. My little Chevy life jacket.
In hindsight, subtle warnings included poor idle (like a small miss), a bit of hesitation, and occasional hard-start.
It's on jack stands in the garage. Just need to find the time to tackle the Optispark removal. Then I'll find out what 2 years and 10K miles looks like on a Petris unit.
If it is the optical component, I have two Mitsubishi originals on stand by.
Meanwhile I've been enjoying the '94 Miata. My little Chevy life jacket.
07-01-2018, 08:37 AM
#40
Drifting
Thread Starter
From my reading, Chris Petris has a good reputation with these things so I don't want to jump to conclusions. I suspect my work more than his. Although I can't confirm that he uses a Mitsubishi sensor.
I haven't removed it for a post mortem yet. Between work and life, it's been a busy few weeks. It could be as simple as a failed timing cover seal.
I hope to pull the Petris Opti next week and we'll all have a look.