305 tbi to 350 tpi computer/key problem
 

I had a 305 tbi in my 92 rs Camaro and I swapped it to a 350 tpi. I also switched brain out so now my key wont work. any ideas?:hmmm:

Re: 305 tbi to 350 tpi computer/key problem
 

well the key is for the computer for the 305 and I changed computers. is there a way to trick it?

Re: 305 tbi to 350 tpi computer/key problem
 

https://www.thirdgen.org/forums/tech...formation.html



More info on how you did the swap would help
Is the orginal VATS wiring connected to the new ECM ?

Re: 305 tbi to 350 tpi computer/key problem
 

The computer for the 305 has 4 numbers on it, the first one is marked Serv. No. 1227165, the second is 868461, the third is M712724017, and the last one is 18068461. The computer that was with the 350 harness is an aftermarket remanufactured module, not sure exactly where from, the label says ASE Engine Control Computer. There is a Number: 7-8746 and a DC Code: 1005YG. I am not sure what a DC code is. The label also has a number on the bottom corner, which may just be a label number: WMA1003, not sure if that would be useful at all. Both harnesses/computers have 2 connectors, one of them labeled A-B with 2 rows of 12 pins, the other marked C-D with two rows of 16 pins.

Next to the computer connectors in the harness is another connector that connects to the harness under the dash. This conector is where the biggest issue is. The harness under the dash in the car and the engine harness are not wired for the same functions in the same places. I am having trouble finding good info that tells me what each of the wires function is, and where they go specifically. I know the connector is called the C207 connector, and have found some somewhat vague pin-outs for it. I think it would really help if I knew what year Camaro the motor and harness came out of, I am guessing '87-'89.

The other issue that crossed my mind is that the car has a Theft Deterrent system. The Key has a chip in it, and I know that this system requires the computer to see the correct signal from the chip in the key to allow the injectors to fire. I am not sure if the replacement computer has this same system, if it matters if it doesn't, or if things need to be "relearned" to each other somehow if it does.

Re: 305 tbi to 350 tpi computer/key problem
 

yes VATS

Re: 305 tbi to 350 tpi computer/key problem
 

Sure you have them the right way around?
That is a 86 - 89 TPI ECM ; not a TBI one

TBI used # 1228746

Open the ECM's up and see what the 4 letter code is written on the silver disc on the memcal (blue chip ) inside each

http://i171.photobucket.com/albums/u...trical/ECM.jpg

Re: 305 tbi to 350 tpi computer/key problem
 

computer is a slave to the vats module I have changed my 91 from tbi to tpi and then to ls and now back to tpi never changed keys had lots of different computers as long as it a vats style computer and the module in the car matches the key you should not be having a issue

Re: 305 tbi to 350 tpi computer/key problem
 

:iagree:

From what he implies above I suspect the VATS wiring to not currently connected to the ECM ?

Re: 305 tbi to 350 tpi computer/key problem
 

the 4 letter code for the 350 tpi computer
: axkt

Re: 305 tbi to 350 tpi computer/key problem
 

if its not a vats style computer is there a way to disable vats?

Re: 305 tbi to 350 tpi computer/key problem
 

Like I said you are looking at the wrong ECM (unless you have swapped memcals ? )

AXKT is a TBI program (chip ) ; came in the # 1228746 ECM

See
http://www.3rdgenformula.com/92/promcodes.htm

Check out the other ECM

Re: 305 tbi to 350 tpi computer/key problem
 

Once we work out what you actually have

Re: 305 tbi to 350 tpi computer/key problem
 

is there a place to find wire diagrams for this? thanks for the help, I cant wait to hear those horses sing!

Re: 305 tbi to 350 tpi computer/key problem
 

Yes
Once you have the correct chip in the right ECM ;
you should be using the # 1227165 ECM you think is a TBI ECM for your TPI

Re: 305 tbi to 350 tpi computer/key problem
 

the help has got me pointed in the right direction.

Re: 305 tbi to 350 tpi computer/key problem
 

Couple of items here, first is that the '8746 ECM harness is not pin compatible with the '7165 TPI ECM. They will plug together, but not all of the terminals/wires are in the correct location.

Another thing is that the '7165 TPI ECM requires a MAF sensor, not MAP as the TBI '8746 ECM uses. Would also need to install the MAF power and burn off relays.

RBob.