Hi All,

Bear with me. This is long and a bit weird but I need some brain help.
I have a weird short that I want to see if I can get some thoughts on because I am seeing some weird things.

Initial: Starting a couple of years ago, infrequently when I warm up the car and shift into reverse the ENTIRE car dies. If I key off and back on it comes back to life and starts fine. What is weird is if I try to start it in reverse, it works fine (clutch in of course). Over the last few months it has started happening more and more. It happens every start when it is cold now. But after I warm the car up and drive, it usually goes into reverse fine again.

Growing: ONCE, a year ago when I was turning left and put the left blinker on, it died. But starting this week, now the left blinker kills it just like the reverse issue consistently until it warms up. Then it is fine. The RIGHT turn signal has no effect at all!

Some points: 68 coupe. Tremec TKO600 transmission, all new wiring harnesses, Ididit steering column. LED compatible flasher unit LED bulbs in blinkers and tail lights (all lights are LED), Sniper EFI. NO OTHER SHORTS ANYWHERE.

Points so far:
1. The reverse switch seems to share power with the blinkers according to the wiring diagram. So in a way it makes sense they both doing it, but why not the right blinker?
2. I unplugged the reverse lights and it went into reverse fine but the blinker still killed it
3. I pulled the flasher module and strangely it had NO EFFECT. The blinker still killed it and the blinkers still blink (that seems odd to me) once warmed up.
4. Once it warms up, it goes away.
5. With the reverse lights plugged in if I try to start it IN reverse, it works fine
6. It has gotten worse over time
7. While I had it running I turned on the headlights (with the electric motors), fuel pump, wipers, stereo, and electric fans and no issues at all (as long as I didn't hit reverse or the left blinker (that's weird also because the headlights put power to the left blinker bulb)
8. From the wiring diagram it looks like power fromes off the fuse box (split to reverse light and blinkers) through the flasher module and then to the steering column. The steering column then distributes that to the left or right blinker if the switch is on.

Next steps for me:
1. Detatch the reverse switch on the trans and see if that makes a difference (with the reverse lights hooked up). Maybe a bad switch?
2. Pull the connector to the steering wheel and apply 12v to the left blinker front, then back, and see if it dies. If not, then I know the wiring after the column is ok.
3. Try the blinker with the steering column connector off and see if it dies. If so there is a possible short IN the steering column
4. Check the grounds for the rear tail lights and the left blinker and look for issues
5. Remove the center shifter cover and follow the reverse switch wires to check for shorts
6. If all else fails, tear the dash apart and look for ground issues (ugh)

I could use some brains to help me with ideas. I won't be working on it in the next week because I am headed to AZ for Barret-Jackson, but will be back on it after that.

Any idea from the Corvette Forum Brain Trust?

 

Tilt Column?
Sometimes they will pinch a couple wires and cause weird stuff.

All factory ground terminals are nice/clean/tight?

 

Yes, it is a tilt. Good thinking. Hopefully the test with the steering connector unplugged will tell me if that is the case.

As far as the grounds, yeah I will be doing a thorough scrub of all of them for sure. I did notice that the left and right blinkers have different grounds, so as far as the blinker is concerned that will need to be ruled out.

 

If there is a wire connection that has been twisted and taped up, don't trust it. It might look good but not making connection. I had a rear tail light that had been added and the wires twisted and taped. It looked good but wasn't making contact. Lots of bubba fixes on these cars.

 

Question-

The whole time it has been doing this- was the sniper installed?

If so- where are you tapping the power/ignition for the sniper.

Rather than chase a bunch of things- reverse-blinkers-column-etc.I'd try to find why the engine is dying.

Next time it dies-leave the ignition on put a meter on the Sniper- and see if it still has power.

You might just need a clean/ switched source for the Sniper. As what you are describing ( warmed up-goes away) it sounds like a computer issue.

Richard

 

The Sniper comes directly off the battery. Positive and negative. It did this before I had the Sniper on too, just infrequently (barely ever back then).
When I say everything dies, even the gauges, fuel pump, stereo. It is literally like I shut the key off.

 

Any kind of car alarm/kill switch (factory or otherwise) ever in the car?

 

i would triple check the battery cables and the battery.. losing all power completely has to be there?
both rear lights and blinker maybe grounding issue in rear..triggering something?

 

Only the mechanical disconnect for the ground on the battery terminal. No alarm or kill switch.

 

Yeah I was thinking that, in a stroke of brain farted-ness, I didn't replace the negative battery cable when I replaced the wiring harnesses.
I have them now and want to do that for sure.

 

I'd look at the ignition switch,

The stereo ( if wired stock) uses the ACC wire- hot in ignition and ACC but not crank. The gauges uses the ignition wire- not hot in ACC but ign and start.

And you'd have the Sniper keyed source off the pink (Gauges) wire as well- as you need hot in ign and crank.

Since its affects both- it really points to the ignition switch/connection / the power source going to the ignition ( fusible link) and
/or the bulkhead connector.

Richard

 

If you pull the flasher, and the blinkers still blink, then you might have pulled the flasher for the hazards, not the blinkers? The blinker flasher is located up under the right-hand section of the dash (at least on my 69), and I think the hazards flasher is near the fuse block.

 

You are indeed correct. I pulled the one that goes into the fuse block. I didn't even realize there was another one.
Learning already.

 

This is definitely a possibility. I have the original ignition switch in there right now.

 

I didn’t read this whole thread, but I don’t think any 1968 had tilt or key in the column. I could be wrong, so feel free to correct me.they had telescopic and standard.

 

Initial post said an Ididit aftermarket steering wheel. No one has mentioned that the key is on the column (which of course it is not).

 

lol I said I didn’t read the whole thread. But that helps. The only way that a blinker could shut off the vehicle is if the blinker wires were in cointact with the ignition switch power wire that supplies voltage to the coil side. The closest place they are in ca intact with each other is in the column or below it where the plug in connectors meet branching off to column and to the ignition switch