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Discussion Starter · #1 ·
I knew it was gonna happen sooner or later and it finally did, she's deader than a doornail. It started a couple weeks ago when the starter didn't respond to the key...but then it did without me re-trying, it's done that twice on different occasions. The alarm has also gone off a couple of times when it shouldn't have, after setting for a few minutes with the door open and then locking it with the electric switch and shutting the door.

Now I get nothing when the key is in the start position, no power to the purple wire on the solenoid. I do have power to to Batt terminal on the dist when the key is in the run position. I have two keys and have tried both, waiting the appropriate time between tries BTW. I turn the key on and the fuel pump runs, plenty of pressure at the schrader. With a remote switch on the startrer, I hit the remote and it fires and runs...momentarily. From that point on there is no more fuel pressure at the rail, no pump running with the key switched on, something shuts down the fuel pump. If I wait several minutes and try again the pump runs again and the car will fire momentarily then no fire..just spin. I've copied and pasted GrumpyVettes sequence of events for the L-98, so I'm familiar with the sequence and am wondering about oil pressure, although that would indicate two problems occuring somewhat simultaneously. Not impossible, just improbable.

If the VATS only cuts out starter engagement, where is my fuel pressure going? Shouldn't it still run with a remote on the starter and the ignition on?

I pulled the codes and get 15/coolant sensor circuit high {voltage high?}and 46/vehicle anti theft fault.
Thanks to a lot of help from the info on this site {THANKS GUYS :cheers: } I think I've narrowed it down to the VATS.

I know I should have taken the other good advice and bought a Helms manual by now......but I haven't ..and now I'm sorta stuck.....

:huh: What do I do now that I think I know what the problem is?

I know "what" now I need "where" and "how", if it's that simple.

Next I'm going to pull the instrument cluster and bypass the VATS at the starter relay as per MAVEN in Kubs "Can't starts my 90" thread and see what that does.

Thanks in advance for any help.

I hate my car.:D
 

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I don't know for sure, but I bet the Code 46 is inhibiting the fuel pump through some means. Bypass the VATS like you plan and it will probably clear it up.

Steven
 

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Discussion Starter · #3 ·
I don't know for sure, but I bet the Code 46 is inhibiting the fuel pump through some means. Bypass the VATS like you plan and it will probably clear it up.

Steven
Thanks, I'm hoping so. But I'm still confused.

I've been reading on this site, http://www.joestradingpost.com/vats/ and I'm wondering if the "starter enable relay" mentioned in the 1986-1989 section is the same bypass location that MAVEN is talking about. I'm thinking not, but if it is, I don't see that it bypasses VATS entirely, just the starter enable relay. Which might make the key activate the starter, but wouldn't I still have the same problem with fuel shutoff? If I am understanding things correctly, in order to completely bypass VATS I would need a re-programmed chip for the ECM that doesn't require VATS signal.

Is it possible that the ECM has just gone bad?

Sorry for all the questions, I'll tear the dash apart this weekend and start jumpering.

Is it possible that it could be anything {like a door switch} in the theft system that would freak out the ECM?

:huh:
 

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http://vats.likeabigdog.com/ Here's a little information on VATS. It seems to be accurate in the description of operation. VATS does shut down the fuel pump relay as well. I don't know about the procedure of by-passing the VATS system. Read at your own risk..
 

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Discussion Starter · #5 ·
http://vats.likeabigdog.com/ Here's a little information on VATS. It seems to be accurate in the description of operation. VATS does shut down the fuel pump relay as well. I don't know about the procedure of by-passing the VATS system. Read at your own risk..
Thanks, good info there, pretty much the same as on the site I linked to.

When I rip the dash apart I'll check the the ignition switch, the wires coming from the lock cylinder and the starter relay. I'll also check the neutral switch and anything that looks suspect, like ground connections and such.

If I buy a reprogrammed VAT-eliminator chip will I still need to eliminate/bypass the rest of the system? {Pellet key and starter relay} Or will the system work with these items still present?
 

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I could be wrong, but the eliminator chip is just designed to by-pass the resistor part of the lock cylinder. As long as that's your only problem, then the rest of the system should function as it's intended to. If it's a problem in the module, then you are going to be in it a little deeper.
 

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Okay, remember how you just looked at the girls in electronics class and didn't listen to the teacher? Now you're going to pay..:spanked:
 

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Discussion Starter · #10 ·
I could be wrong, but the eliminator chip is just designed to by-pass the resistor part of the lock cylinder. As long as that's your only problem, then the rest of the system should function as it's intended to. If it's a problem in the module, then you are going to be in it a little deeper.

By module you mean the ECM?

For some unfounded reason I think it is the problem....I'm just having a hard time getting my head wrapped around the system.
Too many cobwebs up there!:lookinup:
 

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Discussion Starter · #11 ·
Okay, remember how you just looked at the girls in electronics class and didn't listen to the teacher? Now you're going to pay..:spanked:
:laughing:


:D


I knew this was a bad car for me...................It was just a matter of time!:thud:
 

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Discussion Starter · #12 ·
Being the kinda guy I am, I'd rather find and fix the problem and keep that part of the car original, rather than bypass the system. I don't know why since it's obviously not going to be the easiest or cheapest route, but that is my intent.

Anyone have a Helms they're not using anymore?
 

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You can temporarily bypass the ignition lock with the resistors to eliminate one possibly faulty part. Unplug the VATS connector at the base of the steering column, use alligator clips, resistors connect them up and see if it starts. Try cleaning both your keys with the chip in them with rubbing alcohol first.
If you bypass the VATS that way you can tell for sure if it is the contacts in the lock cylinder are worn down and not making good contact.
If it still acts the same plug back in the connector and keep troubleshooting.
If it starts right up then you've found your defective part.
 

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When I had my 87 I had intermittentstart problems which turned out to be a combination of the lock cylinder not reading the key and the vats decoder module.The only advice I can offer is to check for price on the decoder module when I had my problem local Chevy dealer wanted $325 for module I got the decoder module new lock cylinder and keys from Last Detail for less than $200 and they were very helpful .
 

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Discussion Starter · #17 ·
You can temporarily bypass the ignition lock with the resistors to eliminate one possibly faulty part. Unplug the VATS connector at the base of the steering column, use alligator clips, resistors connect them up and see if it starts. Try cleaning both your keys with the chip in them with rubbing alcohol first.
If you bypass the VATS that way you can tell for sure if it is the contacts in the lock cylinder are worn down and not making good contact.
If it still acts the same plug back in the connector and keep troubleshooting.
If it starts right up then you've found your defective part.

Thanks, I will try cleaning both keys and the leaf contacts in the lock cylinder. I'll also check the resistance at the wires that come from the lock cylinder at the connector on the column with the key in the ignition, it should measure the same as my keys. My backup key measures 1.876 on my ohm meter. I don't have the original key on me at the moment, but both keys have been working fine.

:cheers:
 

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Discussion Starter · #18 ·
WOO de freakin HOO!!!

I measured the resistance at the small wires coming from the lock cylinder and did not get the correct resistance values with either key and wiggling didn't help. I wired up a string of a resistors to the correct value and spliced them onto a pair of insulated plugs off an old car stereo and plugged it into the other end of the connector.......fired right up.

FIXED IN FIVE FREAKIN MINUTES WITH NO GREASY FINGERS!!!:D

YOU GUYS ROCK!!!

THANKS FOR ALL THE HELP!!!

:D :D :D :D :D :D :D :D :D

Now I'll take the wheel off and fix the problem.:thumbsup:

:partyon:
 

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Discussion Starter · #20 ·
Thanks, I'll keep that in mind. I don't mind the system though, so as long as it's working right I'll probably try and fix or replace the lock cylinder.

Man you nailed it right on the head! :thumbsup:

Thanks again!:cheers:
 
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