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Discussion Starter #1 (Edited)
I know this has happend alot lol but I am clueless.

I was driving to work one morning got there ran fine and evrrything. I went to leave and the car just wouldnt start.

I put in a msd opti, coil and icm all new still no start. Check fuel pressure it was at 40psi. We narrowed it down to the coil isnt getting spark. I checked grounds cleand them and still a no go. The pcm is fine im just so lost any input and help would be awsome lol

Also I know its not vats the security light doesnt stay on.
 

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vats doesn't kill spark only fuel.

the opti sends a timing signal to the ecm. this controls spark and fuel. if this signal doesnt happen you lose fuel AND spark.

the ecm sends a signal to the icm. the icm GROUNDS the coil each time it's supposed to fire. the coil and icm get constant power from the ignition switch.

check for constant power to the coil with the ignition switch on first, then trace your way back down the chain...
 

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Discussion Starter #3
Its got power just no spark wires are fine itll crank allday.even hot wired to coil and nothin.
 

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Might want to hook up to an obd1 scanner and check for codes. The 3 ignition biggies dtc's 16- opti low resolution signal missing, 41&42 icm codes, don't light the check engine light and will stop engine from running.

If you diagnose and it points to opti, check the opti wiring harness, and opti cap & rotor. Rotor screws sometimes come off. They should be installed with locktite.
 

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Discussion Starter #7
I put locktight on there the previous owner put a new harness on there and it showed no corrosion. I have a obd cord that hooks into my laptop does anyone know a good program to read codes. All the auto stores dont have anything for 95s just 96 and up. And im probably gonna take it out and double check everything.
 

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Discussion Starter #8
I forgot to say that the old opti had a crack a seal blown and moisture in it thats why I changed it. But when placing it is it possible to put the two metal rings like the ring that spins outside your house to mesure your electric usage. Upside down? The msd instructions were crap and barely explaind anything. I wonder if I did that and the pcm cant get a reading from it.
 

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It just so happens, there's a good, free obd1 scan program available made special for our 94 & 95 cars. Look in 4th gen section, find thread titled "obd1 scan program for free". Click link download program. I believe the file sharing site has freescan and the trial version of DataMaster also. So you can have 3 scan programs.

If you mean, can the opti be installed incorrectly, the answer is yes. www.shbox.com has a good pic of how your type 2 opti should be indexed to install.
 

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Discussion Starter #12
Ok question is the distributor and opti two different components. As in cap and rotor then the shuter andbpick up. I called msd and apparently I just got a cap and rotor and the opti will cost me 500 a deal wants 800 for the whole thing and they wont just sell the opti too me does anyone know a good place to get optis??
 

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The optispark is the distributor of lt1 engines. It contains the cap & rotor like normal distributors, of course of different design. And it has the optical section that contains the optical wheel, optical sensor, and it's electronics.

Jegs and summit racing sell msd opti's for around $500 complete. They also sell GM factory opti's. In fact you just missed the sale where GM opti's were $200.

Stay away from the cheap Chinese opti's that are flooding the market. They are a crap shoot at best. If it isn't GM, MSD, or Dynaspark, it's probably a Chinese made opti.
 

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Discussion Starter #14
Damn just my luck well ill get msd to be safe bc I have the cap and rotor from them. The engine has 135 k miles is there any good mods etx to help the engine last till I get it rebuilt?
 

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The best thing you can do to help your engine last is to do regular oil and filter changes, change air filter when dirty, change fuel filter when needed, and take care of problems in a timely manner.

At 135K miles your engine should still be in pretty good shape if previous owners took care of it.
 

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Discussion Starter #16
Yeah thats the problem he didnt I got the car for a thousand bucks. And my dad bought it for me. It has water in the engine and a intake seal blown. I think a head gasket went too. The interior is destroyed too but I waan restore it. How long can these engines last with care??
 

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Discussion Starter #18 (Edited)
Had mine for almost a yr. So many problems lol. How much would a rebuild average out too in price? So I have a heads up how much my car is gonna frisk me for.
 

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Discussion Starter #19
Ok it was the opti but now its starts idles rough and when I put it in gear it stalls unless I rev really high then switch to D and pull out quick but the car shakes badly and when I stop it stalls I installed new ac delco plugs and still same results any hints?
 
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