My car is doing it to me once again. Same exact symptoms as last time - car sitting outside 100deg ambient and it wont turn over. Disconnected battery waited 5 min and still no go.

I turned the key to the run position and crawled under the car and jumped the starter - the starter turns and the car wont fire.

Who can program the VATS out of the ECC PROM for me? It doesn't need to be there anyway - since I have owned the car I have never had a key with the resistor anyway - The previous owner (I'll call him POS) must have put a bypass resistor down under the column.

 

brookman
I spent this afternoon working on my 87 with the same problem as yours.Mine also did not have a key with the resistor.What i found was up in the dash was the orignal lock cylinder with a key stuck in it all taped together. When the car got hot inside the connection would break where the resistor contacts and then would not start.Maybe the same %^^&* wannbe wrench worked your car too.

 

VATS won't allow the injectors to be exercised by the ECM if the VATS module does not measure the correct pellet resistance. When you jumped the starter (heck of lot easier to do by jumping 12 volts to the purple wire on the clutch safety switch or gear selector switch if automatic) you must have the ignition in run position in order to start the car!
Why don't you get a new ignition tumbler installed which has new contacts that make with the key pellet? 99% of thefts are done by bashing the column and jumping the ignition.
There are two wires (white on my 87)from the steering column that go to a 2 pin connector (orange and brown wires on my 87) and the or/brn wires go to the VATS module. Look for a VATS bypass connected to the or/brn wires, that is where your problem is.

 

I don't know how deeply they did their hack and I really don't want to spend the time to find out. I am going to sell this car after I get all the problems fixed.

On a side note I have been having long starts (5+) secons of cranking. I changed the ECM with a rebuilt from NAPA and it starts within 1-2 seconds now.

SO - can someone program out VATS for me?

 

You can't program out the VATS on an 88 because the ECM gets a signal from the VATS module telling it to pulse the injectors. I'm afraid you are going to have to get off your lazy butt and remove the hush panel above the drivers feet and find the 2 pin connector with orange/brown wire and find out what the previous owner put across that connector to bypass VATS. You can bypass VATS by connecting a resistor the same value as the pellet across that 2 pin connector. Be sure to tell prospective buyers that VATS has been bypassed so they understand the car can easily be stolen. 99% of thefts are done by bashing the column and jumping the ignition. A better repair would be to get a new key with the proper pellet and plug the 2 pin connector with 2 white wires from the steering column into the mating socket with the or/brn wires, that way your VATS works like it is supposed to. The previous owner may have bypassed VATS because he really needed a new ignition tumbler which has new contacts in it that make connection with the pellet as the old tumbler became intermittent or failed altogether.

 

I don't have VATS on my 92 coupe and from reading all the problems with the system, don't want or need one. What a PIA.

 

Well what do you expect to find on C4Tech? Post after post of how C4's just run and run and run? People are here to find solutions to their technical problems. I own and drive everyday since 1989 an 87 vette and my VATS stuck me at church one Sunday about 5 years ago. I bypassed it with a resistor and as soon as I could had a new ignition tumbler installed and I have had no trouble since. I don't consider that a lot of trouble. The previous owner bought a new 90 vette and one day they came out of work and found the drivers window busted, the steering column busted, but because of VATS the car didn't move even an inch. That won't happen with your vette,........it will be gone and then you will find out how little your insurance company will give you for it! Keep your car in good repair; take of your car and your car will take care of you!
When your headlight burns out are you going to epoxy a flashlight onto the hood?

 

Not to start an argument - but.... I am pretty sure you can program out the VATS in the EEPROM. THE 165 ECM was used in many cars around those years and they did not all use VATS. THe only difference in the computers was the EEPROM.

And who the hell do you think you are calling Lazy? I spent all day yesterday fixing crap on this car (water pump, Oil Cooler , etc) I am fed up and after I get that done the piece of SH*T wont start.

 

Yes, you can deleat VATS on an 88, it is just a simple flag switch in the .bin file...takes all of 2 minutes to make the change and burn the new prom.

 

Gee, JFB, I didn't mean to p in your post toasties. BTW, I do keep my ride in good repair.

 

My ignition lock jammed and I could not shut off the motor on my 86. I bought a new lock which comes with a non vats key. You have to take this to the dealer or a locksmith and have the correct vats key cut. I haven't done this yet, I just had the VATS flag unchecked in the ECM and it runs fine without the VATS key.

 

i agree. the chances of a C4 being stolen for the reasons it would have 15 years ago are about dried up......the criminals have moved on. its not a main target anymore; the fear of which is outmoded and practically obsolete.

VATS is these older cars is just one big pita. it would be better to once in for all rid yourself of it by having someone remove it from your prom.

 

If I am not mistaken , even if Vats goes bad you will get a no start NOT a no crank condition. Maybe a starter relay if you can manually jump starter, OR you could have a weak battery and a picky starter solenoid.

 

Vehicles with the GM VATS (Passkey) system have a resistor embedded in the ignition key. If the VATS decoder module does not measure the proper resistance when the vehicle is started, the starter and/or fuel pump may be disabled for up to 10 minutes.

This is from more than one source.

 

Even for a weekend wrench it is relatively expensive to install a new ignition switch with two keys and the two tools needed.

However, it is fairly quick work to drop the DS hush panel, locate the small connector (it should be near the bottom of the steering column) with the two ignition wires and see if there is a resistor plugged in that may have come undone. If not, just measure the resistanc of your key and plug the corresponding 1/4 Watt resistor into the connector to get the car ready for sale.

 

OK, so mine is doing the exact same thing right now!!! What foot do I have to stand on, mouth position, incantation to recite, so this doesn't keep happening?!?!

This is twice today!!

-Evan

 

Mad Maxwell, here is what you do.
First try your spare ign key as its pellet contacts aren't as worn like your everyday key AFTER you have waited at least 6 minutes after you attempted a crank. If no go, you might have a bad ign tumbler and you can prove it by dropping the hush panel above the drivers feet and find the two white wires from the steering column that go to a 2 pin connector. With the ign key in place, unplug the 2 pin connector and measure the resistance across the two white wires. It should measure the same value as the pellet. If over 13k ohms, you need a new ign tumbler which has new contacts that make connection to the pellet. Until you can schedule the repair, you can bypass VATS with a 1/4 watt or higher resistor from Radio Shack with the same value as your pellet and connected across the 2 pin socket (or/brn wires) that goes into the wiring harness (goes to VATS module). I recommend that you DO NOT permanently bypass VATS because 99% of thefts are done by bashing the column and jumping the ignition. This happened to the person I bought my 87 vette from to their 90 and the 90 stayed put!

 

jfb,

Thanks for the information. I may wire up a hidden switch to use in an emergency with a resistor.

This is the first time it's been a real pain. I actually had to leave it in the parking lot over night and I'm hauling it home on the car carrier today...

-Evan

 

My vote is for a resistor and switch. Take your key to a good electronics store and have them measure the resistance across the pellet. Then find the proper resistor and measure the resistance. You can find a perfect match if you check a dozen or two. The resistors vary a great deal. Wire in line with switch and you have the best of both worlds. Turn VATS on when you want it on. After new lock, new relays, hours of tracing, several modules, I should have bypassed vats years ago. I believe Vats is programed to shut your car down at the worsed possible moments. Like at the gas pump, in line at a funeral, just after you told a bunch of people how great your car is and you jump in and it won't start.