i have a 92 bird previos 3.1 we just swapped it to a speed density tpi system.. i have a brand new harness from gm a 730 ecm that is out of this car as well as the stock mem chip and a burned chip. both chips have the vats still in them and the car will not crank.. i bypassed the pass key module just to test the starter and the engine rolls over fine however it had no spark. when i hook the passkey back up the engine wont crank again.with or with either chips. i assume this is a vats probem.. but the key and the ecm are out of this car why wouldnt the passkey mod see that the key is correct?? would having the vats removed from the chip fix this??does the memcal chip affect the passkey?

 

If the car wouldn't crank then there is a problem in the PassKey system (a separate module). Best bet is the bit flip in the EPROM to prevent teh ECM from checking for the VAts signal. Or of course fixing the VATs progblem.

RBob.

 

Is your Security light coming on for two seconds and going out, staying on until you release the key, or not coming on at all.

 

how would i do this?? bit flip? i still am a little lost why all the sudden after the swap would the key just not work. the pass key does hook to the ecm correct? i was thinking maybee theres a bad ground or somthing but im not sure.

the security light stays on when the cars pass key is byassed but when the passkey is back in it comes on then i think it goes off.i will check again later.

thx

 

VATS input is F10 on the ECM.
I'm thinking theres a wiring error at the passkey module somewhere.
It controls the starter via an internal relay (pretty sure) and also outputs to the ecm to fire the injectors.
Removing VATS from the program may just leave the Passkey module dead and it may never crank or allow the injectors to put fuel in. I think I'm correct in that, if not someone chime in please.
I would bypass it and get it cranking so you can move on to the next issue. They may end up being related.
The "no spark" would be another issue that I think is unrelated.
You'll need to look into that once it cranks.

 

yea theres no power coming from the ecm to the distributor but the coil has power. i dont get it also if i check the red and black wire for ground its not grounded??? thats why i say maybee its a ground?? i dont understand all this considering this was pretty much just plug and play i didnt have to modify any wires i just plugged it all in.

symptoms that may help or may or may not be related.

wont crank.
no spark.
no ground or power at distributor wires/ but power to coil.
car only cranks if passkey is disable.
flashes code 12 so the ecm is working i assume.
security light stays on when key is on crank mode but shuts off when i let go.
................................................................................


what gives the ecm the ok to run the distributor?
what does it mean if the security light doesnt come on..comes on then off or just stays on?

 

If the light doesn't come on, there is the possibility that the key contacts and lock cylinder contacts are worn or a wire for the lock cylinder is broke. If the light comes on and goes off in two seconds or so, then the system is working normally. If the light comes on and stays on, then the VATS control module is not reading the correct resistance value in the key and you must wait 5 minutes before attempting to try again. This is because there is a time delay inside the VATS control module that must reset. Any attempt to restart the car before five minutes have elapsed will only extend the waiting period and the frustration. This could be caused by the use of the wrong key or a problem with the VATS control module. Since you are not getting a trouble code 46, there is the possibility that VATS is not the actual problem. Or if it is, then the problem would be in the lock cylinder wiring or the key. Have you checked to make sure that the VATS control module is properly connected in the circuit. Have you checked the purple wire at the starter solenoid to see if there is any voltage there with the key in the "start" position. Have you looked at the Clutch Start switch connector?

 

no security light comes on

 

there is no power to the purple wire at all and the car is auto but yes i check the complete starter circuit it stops at the bypass box no power comes out when its hooked up.. i wire a resistor in right at the box correct?

 

Do you have two keys for the ignition?

 

This may help with the distributor.
I put the ECM pin numbers on the left side.

The picture shows the wiring but mine has a reverse adapter on it.
yours probably will not.
Use the ground terminal as your reference.

 

nope just one set of keys.

it still makes me wonder shouldnt there be power coming from the harness tho for the dist wires you showed? because when i tested them none had 12v

also could i check to see with a multimeter the continuity of the key lock wires that are known for breaking???

 

What chip are you using while you are doing this testing. Are you using the stock 3.1 chip that came with the car or are you using the custom burned chip. If you are using the 3.1 chip, it won't work with the V8 engine. If you are using the custom burned chip in the 3.1 memcal, it won't work either unless you have replaced all the chips in it with ones suitable for the V8.

 

i have two chips in a v8 memcal with the zif socket. the first one is the stock 350 tpi chip and the second one is the burned one.
thx
:hail:

 

forgot to mention a very important detail... the tpi setup was maf but we are using a speed density setup ecm and wiring. so maybee the maf distributors are different?

 

Have you converted the engine to MAP yet and as far as I know the distributors are about the same.

 

i believe so .. if your refering to having a map sensor setup.

 

I did find while doing the rewire of mine that the Corvette (LT1) distributor wiring is EXACTY backwards of the F L98 setup.
A recheck is really needed just to be sure where you are at on that issue.
Hope you find that VATS problem soon, sound like its really holding you up from getting everything going.

 

ok will it hurt anything if i get a connector and hook them up reversed? as far as the vats goes the hardest part is that i dont even know if thats what it is . i mean yea the passkey isnt working but that is probraly just a key issue i dont think the vats would stop the car from cranking because they are seperate.

 

I don't see any way that being backwards would damage anything, just wouldn't output pulses to the ecm.
The best way is to check for the ground terminal (either A or D) that will indicate the way the sequence of the wires will go.
You should be able to test this by jumping a wire from the positive terminal on the battery to the "REF Pulse HI" wire going to the ecm.
The fuel pump should turn on for two seconds each time you apply power to the wire.
That's how I figured out mine was reversed.
(aftermarket dist adapter harness, was from a Vette butI was rewiring from scratch and didn't realize the problem)

I would say screw the VATS module and bypass it so the car cranks. You've messed with it enough.
then move onto getting the spark and the engine running.
If you can burn a prom and remove VATS do it now, that way you are sure the injectors will be firing if they have power.
Even if you bypass the Vats module to get cranking, the injectors wil NOT fire unless Vats is satisfied.
If you can't burn a prom now, buy a VATS simulator on e-bay or something to give the ecm the signal to operate the injectors.

After the motor runs, go back and recheck the wiring of the key switch resistance wires, etc and fix that Vats module to be original again.
JP

One more thing I just thought of,
Could the new wiring from the key switch to Vats module have increased the resistance of the circuit?
That will kill the whole she-bang!
Measure the key with Ohmeter, then put the key in, disconnect the two wires at the module and measure again.
If there is a big difference, that's the problem.
I have a PDF file listing the ranges of resistances for each key.
I'll send it via e-mail to you as a ref.

 

got spark now,, , but still wont get fuel to fire. also the security light doesnt come on at all.. i believe the pass key resistance is 1,165.

 

That would be VATS key code #5 as listed by the dealership. Have checked the resistance of the key with it in the lock cylinder. What did you do that you got spark. Have you checked the wiring and connections for the fuel injectors?

 

ok ..i tested the pickup and it worked so i replaced the coil and cleaned some realy dirty connections on the inside of the distributor that hook to the pick up. and it had spark. it spuddered a little bit so i know it would run if it had fuel. i tested the injectors with my 12v test light and it looks like they have power on bith wires with the key on . not realy sure if that helps to know but i was just curious to see if there was power. next im gonna test the ignition to see what the resistance is in that but my multimeter isnt working for some reason i think some idiot was playin in the garage and stuck it in the wall or somthing. lol

thanks

 

who the hell would be dumb enough to stick that meter in a wall:lala: lol

 

make sure the timing is set at 6 BTDC.
Didconnect the bypass lead to the distributor and check with a timing light while cranking.
You can get a "noid" light at the auto parts store for $4 and put it on one of the injectors to see if they are actually firing.
The ECM switches the injectors to ground to operate them. Having power on both sides (without them flashing) indicates they are not being actuated.
VATS will disablethe function if the ECM is not getting the signal from the vats control module.
The ecm needs to get a 60Hz square wave signal from the vats module or you will not get fuel.

Can you burn a chip and disable VATS?
If you can, now is the time to do it.
JP