2kbluestreak

Recent history first: My 2k coupe with 43k started but barely idled. Restart and it fired and revved OK. Four hours later, same thing, so I left it in my garage not trusting it would start & run again. Tried start next day crankvery well a few times, but no fire. (I'd only crank for about 5 seconds not wanting to overheat anything elelctical.) Spark? Timing? or Fuel? Within a couple minutes, I push the plunger on the fuel rail Schrader and get no gas or pressure.Next try, I get the "SECURITY" light and dash flashing in sync with a ticking from the passenger footwell. After charging the battery for 10 hours at 6 then 4 amps, I take it to Autozone and they say it's only 60% charged, so I get a new Duramax 1000 amper. Install new battery and turning key to the "on" position results in the flashing. Meanwhile, I remove the fuel filter while leaving the lines open. Reading that the flashing "SECURITY" means a VATS problem, I start the 30 minute VATS relearn procedure. In the first sequence, the dash stopes flashing after 8 minutes, but I let it go to 10 per the instructions. During the second sequence, the dash continues to flash all the way through, althoug the frequency was getting fown to once every 15 seconds. Do the third secquence and the flashing stops after 8 minutes, so I wait for 10, turn the key to "OFF", then try to crank. Nothing. Try the sewuence for a 4th time, and it's just like the 2nd: some flashing past 10 minutes. Try to "START", and no crank. Have lunch and go back and try to start and engine cranks, but wont run. I do find some gas has come out of the fuel line indicating the fuel pump must be working. I try the whole VATS relearn, and engine won' "CRANK". I next try to read the DTC codes per the procedure and get nothing on the DIC. Pull the key and try to re-insert to try again, and key won't go in. Spray contact cleaner in the lock and key goes in, but DIC won't show anything. Pull the key and try again, but key won't turn, which is where I am now.

I think I need a new key becasue it won't turn both keys, evening turning upside down. Electrical contacts might be bad, but the wole ignition unit comes with both mechanical and electrical parts. Any helpful suggestions will be apprecviated.

2kbluestreak

Update: While home at lunch I tried starting again and both keys went in and turned the ignition switch to the "CaranK" position with no SECURITY flashing. Engined turned over very slowly,; not enough to start, plus there hasn't been enough time for the fuel pump to fill the rails.
Battery voltage yesterday was 12.65 v befoe trying the VATS relearn and 12.45 after. During the middle of attempts, the DRLs would not light any more, and I should think that 12.4 volts would allow this. Anyhow, I'm charging the battery a little more while I'm back at work.
Don't think I could trust the key part of the ignition to ever be reliable again.

BigGun

You might indeed need a new ignition switch but you should at least take it apart and look at the contacts. Are you sure the battery cables are in good condition and have you checked at the starter end of the cable. I wouldn't worry about the fuel end of the equation yet.

Bill Curlee

WOW! Something is very not right with your electrical system A new 1000 Amp battery should throw lightning bolts. You really don’t need a 1000 amps BUT,, it wont hurt anything.

Can you move your battery cable terminals by moving the cables?????

If you can, that could cause the issue. TIGHTEN the terminals to 11 FT/LBS and make sure that they are clean and free of damage. Inspect the CRIMP where the wire attaches to the terminal end and make sure that it’s not burnt/corroded/loose etc...

When you connect the battery to the electrical system you power up the following components:

Alternator
Eng Compartment Fuse box
Passengers Foot well fuse box
EACH MODULE (PCM, BCM, IPC, RDCM,LDCM, SCM, ETC ETC... (hot at all times buss.
Feed to the starter solenoid
Headlight control module

Measure the voltage on the B+ terminal on the eng comp fuse box to ground, the BATT terminal on the back of the alternator and see if you have full battery terminal voltage.

What is the output of the alternator when the engine is running? Measure directly on the battery terminals.

BC

2kbluestreak

Thanks Mr. Curlee and BigGun:

Voltage last night from a couple hours charging reached 12.6 v.This morning it was 12.4 v at the battery terminals and 12.4 v at the engine fuse block B+ terminal and the big wire at the back of the alternator. Is this normal to loose .2 v ovenight with nothing on?

I decide to charge some more, and while this was going on I pulled the ignition switch and took off the green cover. There was one contact point on each side that was solid black and a little 1/64" spot of black on another, This applies to the contact blocks in the base and the ones on the fingers. A little rubbing with 2000 grit paper had them shiny again. No pitting or corrosion was present. I reassembled the ignition assembly and plugged it back in. When I turned the key to "ON" and the DIC scrolled "Corvette by Chevrolet" I knew everything was back to normal. Turning to "START" fired up the engine after a few more revolutions than normal in order to pressurize the fuel rails. Imagine all this trouble and nothing electrical working because of a little carbon on two tiny contacts. I was finally able to access the DTCs and found only some History ones at LDCM, RDCM, SCM and RFA, which I deleted. After my next couple drives I'll do a diagnostic again and see if anything pops up.

Since the engine can now run, my voltage at the battery terminals is 14.5 volts. Thanks again Bill Curlee for you previous posts on identifying the cause of this type fo problem and showing us how to fix it. My switch contact terminals look so good now, I can't see how a new switch would be any better. Like to save $$.

Bill Curlee

Good job on the repair!



Bill