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I was driving down the highway about 70 and the car just shut down, the engine just quit. I pulled to the side and was able to get it restarted eventually and was able to go another 5 miles or so and it shut down again. After about 15 minutes, it restarted and I went another 10 miles or so until it again shut down. This time I didn't think it was going to restart. It would crank and try to catch occasionally. It finally did turn over and I was able to limp home into the garage (it actually seemed to run ok). When it was running, it would kick and drop out very briefly at times. When it shut down, it just turned off and I would coast down the road. I backed it out of the garage this weekend and it fired right up both times.
Using the paper clip I saw an H16 at the 4.0 ECM portion. Not sure what it is or where to go from here. I did replace the Opti about 2 years ago.
I saw this elsewhere:
Code 16- Low resolution pulse (distributor). ECM is not detecting the 4X pulse from distributor. Check wiring connections, especially the pigtail connector from the optispark to main wiring harness. This is the black/red wire that goes to terminal "A" on the pigtail connector. On the 1992-93 ecm, this is wire C5 (green connector). 1994-95 ecm, this is wire B2 (black connector). If wiring checks out, you will have to replace the optical sensor module in the distributor.
I'll check the wires, but not really sure where to go after that.
Well, after all these months I finally got around to (nearly) completing the job. New opti installed, plugs and wires, H2O back on (still dry though until I can start it up in case I have to tear it all apart). However, I have 3 things that are not connected and I don't recall where they go. The first is the tube that comes out of the top of the air funnel (in front of the TB) that is just behind the MAF. I'm not certain where that is supposed to go.
I also have two similar connectors coming off the wire that goes to the drivers side plug (temp?) of the water pump. One black, one grey. They may actually not go anywhere, they are very short and I see no other place nearby for them to plug into. I don't remember unplugging them and I didn't mark them with my hi-tech masking tape method either.
Where does this tube from just behind the MAF connect?
Where do these plugs go? One black one grey? In between the light and power steering pump.
One other question/confirmation, where is the vent of the Opti supposed to plug into?
Sorry for the elementary questions and appreciate the help. I worked on this as I could and it has been months since I pulled it all apart. I am not anywhere near proficient in motor works, but I promised myself that when I got my Corvette, I would try to do any of the work on it I could. Other than these 3 connections, I think everything is good to go.
The tube behind the MAF feeds the Opti for fresh filtered air. There should be a nipple on the opti.
The 2 plugs, ( 1Black and 1Grey) plug into the MSD Coil
Yes! Thanks Frankie, I now remember those 2 kind of going into the coil together. It was blocked by the hose, so I'll drop that wire below the hose.
So where is the opti vent hose to go? Just hang down there to drain I assume? Also would like to find out what is supposed to connect to the nipple on the front of the throttle body just below the air intake?
I can't wait to get her running again, it's been too long.
So where is the opti vent hose to go? Just hang down there to drain I assume? Also would like to find out what is supposed to connect to the nipple on the front of the throttle body just below the air intake?
The opti-vent requires an "in & out" so I'm guessing that the nipple you have in question is where the hose that you have questions about belongs.
See that tube below where the TB was (this is not mine)? I am wondering where that connects to?
That isn't the other arm of #16 in the pick WVZR linked to is it? I don't see how that would go to the drain of the Opti if the other tube just aft of the MAF sensor is the "in" connection to keep the Opti dry. I would think the drain just hangs loose under the car to drain.
I can get a pick of mine tonight if that helps. I just want to get this buttoned up and running again. Thanks for the help!
See that tube below where the TB was (this is not mine)? I am wondering where that connects to?
That isn't the other arm of #16 in the pick WVZR linked to is it? I don't see how that would go to the drain of the Opti if the other tube just aft of the MAF sensor is the "in" connection to keep the Opti dry. I would think the drain just hangs loose under the car to drain.
I can get a pick of mine tonight if that helps. I just want to get this buttoned up and running again. Thanks for the help!
Tube below the TB connects to the PCV valve, I believe.
The opti does not have a "drain". Vacuum comes from the tube that connects to the intake manifold, the tube from behind the MAF supplies fresh air into the opti so it doesn't implode from the vacuum. The constant circulation of fresh air is what keeps the opti internals dry.
Sorry to be so dense about this, but I tore it all apart back in June and can't recall where this nipple below the throttle body connects to. I've looked through the red mechanics books (1 & 2) and can't locate anything about it. I'd really like to get this completed today.
Sorry to be so dense about this, but I tore it all apart back in June and can't recall where this nipple below the throttle body connects to. I've looked through the red mechanics books (1 & 2) and can't locate anything about it. I'd really like to get this completed today.
6D4-5 in the FSM shows how the Opti is vented in a pretty good image and shows using the front port you've questioned and doubted. The image I posted earlier was from a '96 SPO publication that I assumed would help you if that fitting wasn't accessible from the location that was mentioned and I'm quite sure it's not. I thought you could use it a a guide to venting and there's "NO DRAIN" as you keep insisting. If the vacuum harness from your opti isn't constructed correctly with 2 valves it may have been abandoned in error.
6D4-5 in the FSM shows how the Opti is vented in a pretty good image and shows using the front port you've questioned and doubted. The image I posted earlier was from a '96 SPO publication that I assumed would help you if that fitting wasn't accessible from the location that was mentioned and I'm quite sure it's not. I thought you could use it a a guide to venting and there's "NO DRAIN" as you keep insisting. If the vacuum harness from your opti isn't constructed correctly with 2 valves it may have been abandoned in error.
The opti I am trying to install seems to be missing a connector port. The one that is there, I will connect to the air intake behind the maf. I thought the one that seems to be missing from the opti I have, was a drain of some sort. So, if this connection goes to the air intake, I still don't have anything to connect to the port below the TB. I'm confused?
Car shuts down ECM=H16
