great421

iTrader: (1)

96 LTI / M6

Anyone have experience with this code?

My GM manual says check the diagnostic "Cranks but does not Start" aids, then replace the Opti or PCM, but both are less than 6 months old.

Thanks in advance!

MIKE (great421@yahoo.com)

Alex94TAGT

A DTC 1371 is for the low-resolution circuit of the Optispark's optical sensor. Of the two signals coming from the opti, this is the more important one -- the car can't run without it (no spark, no injectors).

I would suggest that you first check the wiring harness. You can check for continuity up to the PCM with a voltmeter, but I'd also suggest inspecting the electrical connectors as well -- I've had the internal contacts snap off of the 'female' end terminals.

If it turns out that you need to tear back into it, and the cap/rotor are new, you can technically get a 'rear-plate only' with the optical sensor from the autoparts stores. I did that for years without any trouble, plus it's only about $150.

great421

iTrader: (1)

Alex -

Thanks for the input.

I actually thought that I found the problem yesterday; I removed the TB to gain access to the 4 pin connector on the Opti and the top of the Weather-pack connector was all f*ck*d-up and 'repaired' with electrical tape; I replaced this jumper harness ($140 at the dealership!), buttoned it all up and Ta-Da!!! It started! Ran like a champ too for about 2 miles then it died again and threw 1371 again (WTF?!?!).

So, after checking wire 453 from the PCM to the 4 pin connector (like my GM manual says), I'm of the midset that the Opti has failed internally either from contamination or installation. If the 'master technician' who installed the Opti here in NC thought it OK to 'fix' a damaged wiring harness the way he did, what's to say that his Opti install was any better!

So, this begs the question: is there an Opti R&I procedure located here on the LS1Tech site or should I go somewhere else? I surely do not want to let another dealership monkey 'fix' it again, and I now have my garage fully stocked and my compressor has been relocated from MI as well, so - I (probably) have the tools and the technology to make this happen, I just need a step by step - Any Advice?

Thanks (again) in advance!

MIKE

BOLO

iTrader: (40)

I feel your frustration. The 'ol optispark on the LT1 is one of the most sensitive part of the ignition system that proper installation and preventive maintenance and precautions must be maintained in order for it to live a long troublefree life.
Moisture is its ENEMY.ie,undercarriage wash, or when servicing the waterpump(do not get the opti wet). I've had my shares of experience with this ignition system.
I've owned my camaro since new and had only replaced the opti twice. The 1st time was because of the above,too many undercarriage washing and the 2nd because of new mods(heads/cam). It really did not need replacing, but since the engine was apart for the new cam, I figured put a new opti aswell.
Keep checking within this site, I'm sure theres a write up on this topic.

Alex94TAGT

Hey Mike.

That optispark harness was $140 from the dealership? Yikes!!! I think you can get it online for around $50. Even though it apparently didn't fix the problem, it was a good idea to replace it (since it was hacked up).

-------------------------
It seems all the online guides to replacing the optispark are down. Good thing I'm on vacation!

There isn't too much to replacing the optispark -- worst part is pulling the waterpump and having coolant spill everywhere. Only special tools you'll need are perhaps a few extensions and swivel-sockets, and a bucket / tupperware container to catch coolant. You'll need new waterpump gaskets as well as a few jugs of coolant, which you can both get from the local autoparts store.

In general:

1) Get front of car up on ramps. (I like ramps better than jackstands.) Since the car's not running, you can use a wooden 2x4 to jack directly on the k-member. Make sure the rear wheels are chocked / e-brake is on / in-gear if manual tranny.

2) Drain all coolant from radiator -- open the stopcock on the bottom passenger side of radiator. (FYI, you'll still have plenty of coolant in the block even after this, which is fun when you eventually pull the waterpump.)

3) Remove the intake ductwork -- MAF sensor & up to the throttle body. Remove the rest if needed.

4) I personally like to remove the radiator cooling fans so that you have more room to work, but it can be done otherwise. If you decide to do this, they can be bit of a headache. Two electrical connectors (one to each fan), and you might need to pull the coolant level sensor near the radiator fill cap (I don't recall). Four clips hold the fans onto the radiator -- the fans must lift out of these clips, which is obstructed by the radiator hoses and whatnot. So, you might have to remove the radiator hoses from the radiator, which isn't a big deal, as you'll be removing them from the waterpump later anyway.

5) Remove serpentine drive belt (via the tensioner), and remove the crankshaft pulley. Three bolts hold the pulley to the crank hub -- once removed, you might need to tap around the pulley with a hammer to loosen any rust-bonding, then pull it / rock it off by hand. This is done so you have room to remove the optispark from the timing cover later on.

6) Remove AIR pump (if equipped), and the AIR pump bracket-to-block. This has to be done because the AIR pump bracket uses one of the waterpump studs. Not sure if you'll have to remove the coil/ICM from the driver's side head -- I don't think so, but keep it in mind.

7) Get ready to catch coolant as you disconnect radiator hoses from the waterpump (use channel-lock pliers on the hose clamps). Disconnect the electrical connector from the waterpump's temp sensor, and begin removing the six (9/16"?) waterpump bolts. There are three on each side, and some are studs. The passenger side is obstructed by the power steering pump -- it's pretty easy to fish an extension through one of the circular holes in the power steering pulley though.

8) Pull waterpump out the bottom. Try not to get soaked, and try not to bang into the radiator and damage the fins.

9) Remove the optispark harness connector. Label the spark plug boots on the optispark with whatever means possible -- white-out pen, masking tape and sharpie, etc. Three bolts secure the optispark to the timing cover -- remove them, and pull the optispark straight out. If one of the 'ears' of the crank pulley get in the way, you might have to put the car in neutral and turn the engine over by hand (5/8" socket on the center crank hub bolt, rotate clockwise).

10) Installation is reverse of removal! It's vitally important to bleed the cooling system after you get it all back together, via the two brass bleeder screws.

Naturally, I might be forgetting a few small things. Just make a post if you have trouble -- there are many people who can help/elaborate.

great421

iTrader: (1)

Alex -

Thanks again for the write-up and advice - I'm driving a 75 Lemans (with the tick of death! Do not exceed 45 MPH!!!) right now until I get this Opti problem resolved; The 96 is going in the garage tomorrow!

If anyone else has any particular pearls of Opti wisdom - To quote Ross Periot - I'm all ears!

MIKE

great421

iTrader: (1)

Another question; are there seals behind the Opti which need replacing when the unit is replaced? I ask this because I've read where people have stated their Opti was filled with oil. If so, does anyone how the PN's?

great421

iTrader: (1)

OK - The new Accel Opti II should be coming from Summit today; the only hang up in getting the unit off was the three tabbed piece on the fron end of the crank.

After mangling a couple of bolts (to extend the length of the reach on the center bolt for the puller - as the bolt on the puller was a larger diameter than the 5/8 / 16 mm bolt on the crank) I just struggled wtih the Opti itself until it came off w/o removing that three tabbed piece on the crankshaft.

Any suggestions on the best way to proceed with the installation?

Any words of wisdom?

Thanks in advance!

Alex94TAGT

IIRC, you don't need to remove the 'three tabbed piece'. That's the crank hub. As I said before, just rotate the engine by hand until the three ears are out of the Optispark's way.

If you DO end up needing to remove the hub, I would suggest using a long (~6") quarter-inch drive extension with your hub puller instead of using any form of bolt. The 1/4" drive will extend through the hub and press against the crank snout, without fear of bending and getting caught in the crank's threads (as a bolt would).

In regard to your seal question, as I'm sure you can see now, there's a timing cover seal for the optispark. If it's not damaged or leaking, you should be able to reuse it, but it's possible to replace it if necessary. I use a hooked 'seal puller' and/or a screw driver to pull out the old seal. Clean the seal race with some brake parts cleaner, hit it with a tiny bit of RTV, and hammer in the new seal with a rubber/plastic mallet.

You're halfway there -- shouldn't be any surprises now. Again, just be sure to bleed the cooling system when you're done, and test for leaks.

great421

iTrader: (1)

Quick Update - It lives!

I had to "fix" my free replacement Accel Opti II as the 4 pin weather pack connector would not go into hole all the way - manufacturing defects - gotta luv em! Purchased an E4 deep well reverse torx to disassemble the unit ($15 from the Snap On truck!) and got everything together (except for the balancer / crank pulley) quite quickly. The pulley only goes on one way and I was trying to force it on 120 degrees out of phase - I wasted an hour with that nightmare!

Oh well, I'll know better next time!

Alex - Thanks for the write up / advice!