Advice on Missing Keys
Thread Starter
Heel & Toe
Joined: Jun 2013
Posts: 21
Likes: 0
From: California
Advice on Missing Keys
Hi, I have inherited a '91 Corvette (6 speed) it has not been running for a few years and I am not sure what is wrong with it. I am guessing it has some kind of electrical (ECM) issues.
I also do not have the keys. I just called a dealer, and they said they can cut a key for me for the ignition and the "trunk", but there is no value in their records for the VATS system. What should I try to do next? I would like to at least try starting the engine to figure out what is wrong with it. Thanks!
I also do not have the keys. I just called a dealer, and they said they can cut a key for me for the ignition and the "trunk", but there is no value in their records for the VATS system. What should I try to do next? I would like to at least try starting the engine to figure out what is wrong with it. Thanks!
Team Owner
Joined: Sep 2003
Posts: 25,387
Likes: 2,740
Hi, I have inherited a '91 Corvette (6 speed) it has not been running for a few years and I am not sure what is wrong with it. I am guessing it has some kind of electrical (ECM) issues.
I also do not have the keys. I just called a dealer, and they said they can cut a key for me for the ignition and the "trunk", but there is no value in their records for the VATS system. What should I try to do next? I would like to at least try starting the engine to figure out what is wrong with it. Thanks!
I also do not have the keys. I just called a dealer, and they said they can cut a key for me for the ignition and the "trunk", but there is no value in their records for the VATS system. What should I try to do next? I would like to at least try starting the engine to figure out what is wrong with it. Thanks!
Thread Starter
Heel & Toe
Joined: Jun 2013
Posts: 21
Likes: 0
From: California
Yeah... catch 22 indeed!
A VATS delete is an interesting option. A little pricier than I might want to invest in at the moment. I have been reading around a little, it looks like I might be able to insert various resistor values if I tap into the right lines... Were there any common resistor values that were used for this model/year? Could I take out the ECM and have someone determine the right value? Just trying to brainstorm some ideas...
A VATS delete is an interesting option. A little pricier than I might want to invest in at the moment. I have been reading around a little, it looks like I might be able to insert various resistor values if I tap into the right lines... Were there any common resistor values that were used for this model/year? Could I take out the ECM and have someone determine the right value? Just trying to brainstorm some ideas...
Team Owner
Joined: Sep 2003
Posts: 25,387
Likes: 2,740
Yeah... catch 22 indeed!
A VATS delete is an interesting option. A little pricier than I might want to invest in at the moment. I have been reading around a little, it looks like I might be able to insert various resistor values if I tap into the right lines... Were there any common resistor values that were used for this model/year? Could I take out the ECM and have someone determine the right value? Just trying to brainstorm some ideas...
A VATS delete is an interesting option. A little pricier than I might want to invest in at the moment. I have been reading around a little, it looks like I might be able to insert various resistor values if I tap into the right lines... Were there any common resistor values that were used for this model/year? Could I take out the ECM and have someone determine the right value? Just trying to brainstorm some ideas...
I don't believe you mention your location. Where are you?
Thread Starter
Heel & Toe
Joined: Jun 2013
Posts: 21
Likes: 0
From: California
I'm in CA.
I am just thinking ahead since it will cost some dough to get the keys made. The car has been sitting in the driveway unlocked, so I at least have access to the car internals. So having the keys but not being able to start the engine will not be a huge improvement in the situation. But it would be nice to be able to lock it. =) They are going to charge $35 for a code look-up and $10-15 per key (for blanks without resistor chip).
Even if the chip is not present in the key, can I try to turn over the engine and have it run for a couple seconds, or would that be a bad idea?
I am just thinking ahead since it will cost some dough to get the keys made. The car has been sitting in the driveway unlocked, so I at least have access to the car internals. So having the keys but not being able to start the engine will not be a huge improvement in the situation. But it would be nice to be able to lock it. =) They are going to charge $35 for a code look-up and $10-15 per key (for blanks without resistor chip).
Even if the chip is not present in the key, can I try to turn over the engine and have it run for a couple seconds, or would that be a bad idea?
Team Owner
Joined: Sep 2003
Posts: 25,387
Likes: 2,740
I'm in CA.
I am just thinking ahead since it will cost some dough to get the keys made. The car has been sitting in the driveway unlocked, so I at least have access to the car internals. So having the keys but not being able to start the engine will not be a huge improvement in the situation. But it would be nice to be able to lock it. =) They are going to charge $35 for a code look-up and $10-15 per key (for blanks without resistor chip).
Even if the chip is not present in the key, can I try to turn over the engine and have it run for a couple seconds, or would that be a bad idea?
I am just thinking ahead since it will cost some dough to get the keys made. The car has been sitting in the driveway unlocked, so I at least have access to the car internals. So having the keys but not being able to start the engine will not be a huge improvement in the situation. But it would be nice to be able to lock it. =) They are going to charge $35 for a code look-up and $10-15 per key (for blanks without resistor chip).
Even if the chip is not present in the key, can I try to turn over the engine and have it run for a couple seconds, or would that be a bad idea?
The ignition blank can NOT just be any blank, it needs to be a work-key to have the correct blade length for the cylinder.
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Thread Starter
Heel & Toe
Joined: Jun 2013
Posts: 21
Likes: 0
From: California
Interesting. I had the same situation with another car and the locksmith was going to charge quite a lot. I fortunately went through a pile of keys and luckily two different ignition keys worked, since it was a really old car. I have more time to deal with this one...
I am kind of wondering if my dad was having issues with the VATS since I think he swapped out the computer... Maybe he didn't realize the resistance value is matched to the key, is that correct? I found a couple units in the car that look like ECM's which he may have found at a junk yard. Other than that, the engine looks complete, no missing components, etc..
I am kind of wondering if my dad was having issues with the VATS since I think he swapped out the computer... Maybe he didn't realize the resistance value is matched to the key, is that correct? I found a couple units in the car that look like ECM's which he may have found at a junk yard. Other than that, the engine looks complete, no missing components, etc..
Racer
Joined: Oct 2012
Posts: 350
Likes: 2
From: Huntsville AL
Google "VATs Resistor Values". Pay the dealer $35 for the key code then go see an independent locksmith to interrogate the VATs in the car and cut the correct key. (There are 15 possible resistor values for a single sided GM key)
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From: Kingman AZ
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I am not 100% sure on the 91. The 87 I used to own needed a new VATS control module. I got one that was tested from www.vette2vette.com. The test showed that it worked and also gave me the VATS resistor value so I could remake my ignition keys with the correct chip.
I installed it with the correct key and off she went. It is the gray square object in the pic. Probably in a different spot on a 91 but maybe not.
So - buy a used one, ID the resistor value and have the dealer or someone else make you new keys. Sometimes the ignition switch itself is very worn but you can purchase a new one from www.corvettecentral.com and use the keys that come with the switch. They should also be able to sell you a set with the matching pellet.
I installed it with the correct key and off she went. It is the gray square object in the pic. Probably in a different spot on a 91 but maybe not.
So - buy a used one, ID the resistor value and have the dealer or someone else make you new keys. Sometimes the ignition switch itself is very worn but you can purchase a new one from www.corvettecentral.com and use the keys that come with the switch. They should also be able to sell you a set with the matching pellet.
Team Owner
Joined: Sep 2003
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'91 VATS is controlled by the CCM - there is NO module as pictured in the previous post.
OP - these spare "boxes" are black in color with 4 square connectors on one end? If yes then they're ECM's but that does NOT hold the solution to your possible VATS issue. You've been directed to the "first step" by myself and others. In my first post I explained the "work-key" - there is no resistance chip. You mention, "I've got time" - that's good but don't spend that time "scratchin your head" while "brainstormin" - you'll bleed!
OP - these spare "boxes" are black in color with 4 square connectors on one end? If yes then they're ECM's but that does NOT hold the solution to your possible VATS issue. You've been directed to the "first step" by myself and others. In my first post I explained the "work-key" - there is no resistance chip. You mention, "I've got time" - that's good but don't spend that time "scratchin your head" while "brainstormin" - you'll bleed!
Team Owner
Joined: Sep 2003
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The OP just needs to make the "first move" which has been suggested! He seems intent on "brainstormin"!!
Racer
Joined: Oct 2012
Posts: 350
Likes: 2
From: Huntsville AL
I don't know why people recommend buying parts that are common to the GM parts bin from mail order specialty houses. The lock in question was used across multiple GM car lines for a number of years and is availably locally for around $50 AND you don't get GOUGED with 18 to 20% for shipping and "handling".
Thread Starter
Heel & Toe
Joined: Jun 2013
Posts: 21
Likes: 0
From: California
That is an "exception" and certainly not the rule!! Before key control became a "corporate" procedure and not a "car line" controlled feature it varied car line to car line. The Chevrolet policy was very complicated and nearly worthless. It was likely passed on to the OP that it (VATS) would "likely" not be included is what a dealer would mention before the request, there is NO way of knowing before the request. If it is in included with the request then the OP's needs MIGHT POSSIBLY be met BUT it would be advised to have the "work-key" only done first to confirm rotation. If you do the VATS key and it doesn't rotate you've wasted substantially more money. If the VATS is included and the "work-key" doesn't rotate then there's a good chance the cylinder was replaced but the VATS value retained. Then it's buy a cylinder time and start fresh or use other options.
The OP just needs to make the "first move" which has been suggested! He seems intent on "brainstormin"!!
The OP just needs to make the "first move" which has been suggested! He seems intent on "brainstormin"!!
As a first step, I will get the keys made and make sure they fit and then move on to figuring out the VATS code. I have an idea on how to do that with the "work-key" that hopefully will same me some money. Hopefully the contacts within the lock cylinder and wiring are still functioning properly.
Last edited by buchacho; Jun 25, 2013 at 01:13 PM.
Team Owner
Joined: Dec 2000
Posts: 21,094
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From: Phila., PA burbs
I called a dealer yesterday, and the guy I spoke with was pretty helpful. I asked if he could at least tell me what info they could give me before I had to drive to their shop. I gave him the VIN and license plate number and he told me they have the ignition and "trunk" (which he found odd) key codes, but no VATS code. Is the "trunk" key for the doors?? He also mentioned if the lock cylinder was replaced, that it would not work. I did not know if I get the code from the dealer, I can get the keys made somewhere else as suggested here.
As a first step, I will get the keys made and make sure they fit and then move on to figuring out the VATS code. I have an idea on how to do that with the "work-key" that hopefully will same me some money. Hopefully the contacts within the lock cylinder and wiring are still functioning properly.
As a first step, I will get the keys made and make sure they fit and then move on to figuring out the VATS code. I have an idea on how to do that with the "work-key" that hopefully will same me some money. Hopefully the contacts within the lock cylinder and wiring are still functioning properly.
I can tell you how I got mine running pretty inexpensively (however it was time consuming). First I bought a new ignition lock cylinder which comes with a "work key" as WVZR-1 mentioned. After installing that I had an ignition that turned, but obviously would not start as I still didn't know the VATS resistance. I then used a cheap potentiometer to duplicate each of the 15 possible resistances. Once the proper resistance was found the car started. I then took the key with the new found resistance to the dealer and had them cut me a key (three actually) with the proper resistance VATS pellet. It probably took my a few days to do this, but I was only out $100 or so and the VATS is still operational. Good luck with it.
Racer
Joined: Oct 2012
Posts: 350
Likes: 2
From: Huntsville AL
Unrelated, but important: If the car has been sitting out in the weather any length of time, siphon a gallon of gas from the bottom of the tank and check for water contamination BEFORE you start cycling power, even with the "work key". If you find water, clean out the tank completely before the fuel pump has a chance to push that crap through the system (IF the pump works at all)
Last edited by Just BOB; Jun 25, 2013 at 02:56 PM.