98 to 99 pcm swap question please help

[Adam Calley]

Ok ive decided to start swaping my 98 pcm to go to the 99 pcm and so far ive got 4 wires that the 99 have no spot for! Does anyone know where these wires are supposed to go??? On the 98 its labeled pin 24 Blk/wht-sensor ground jumper. Pin 55 DK GRN/WHT- VSS OUTPUT SIGNAL. Pin 69 BRN-EVAP PURGE VACUUM SWITCH SIGNAL. Pin 75 GRY-LEFT AND RIGHT FUEL TANK LEVEL SENSOR GROUND. These are the explanations that my 1998 manual gives me for these wires but i have a wiring diagram i bought for a 1999 corvette offline and i can't find a spot for them, please help me or call my if you wish. 336-225-7932. Thanks Adam Calley.

[driver456]

Ok ive decided to start swaping my 98 pcm to go to the 99 pcm and so far ive got 4 wires that the 99 have no spot for! Does anyone know where these wires are supposed to go??? On the 98 its labeled pin 24 Blk/wht-sensor ground jumper. Pin 55 DK GRN/WHT- VSS OUTPUT SIGNAL. Pin 69 BRN-EVAP PURGE VACUUM SWITCH SIGNAL. Pin 75 GRY-LEFT AND RIGHT FUEL TANK LEVEL SENSOR GROUND. These are the explanations that my 1998 manual gives me for these wires but i have a wiring diagram i bought for a 1999 corvette offline and i can't find a spot for them, please help me or call my if you wish. 336-225-7932. Thanks Adam Calley.

Pin 24 Blk/wht-sensor ground jumper(DISCARD)Pin 55 goes to red plug pin 50.Pin 69 not sure.Pin 75 goes to BLUE PLUG pin 23

[Adam Calley]

OK before i make a huge mistake here someone please clear this up for me. My 98 manual says c1(connector 1) is the red connector and c2 (connector 2) is the blue connector. and the 99 is totally opposite right? I think im thinking about this way to hard but just clear that up for me. thanks Adam

[ChipsByAl]

OK before i make a huge mistake here someone please clear this up for me.

You are correct. It sure makes it confusing.
Al

[Adam Calley]

Thank you man i appreciate it, im glad im not the only one gettin confuesed, do you have any idea where pin 69 goes its the evap control wire or am i not going to have the evap system working anymore after this swap?

[driver456]

Also on the 97-98pcm pin 44 on the BLUE plug"DISCARD"(Fuel level sensor's 5.0 volt feed)

[Adam Calley]

why do you discard pin 44, fuel sender 5 v feed, cause i found the spot with the right circuit number to put it?

[eurospec1]

why do you discard pin 44, fuel sender 5 v feed, cause i found the spot with the right circuit number to put it?

It is an extra 5 volt feed for the 97 fuel level sensor, now, you are retaining the 97 fuel sensors in your car but the way the new PCM will read your fuel level is different, so that 5 volt feed is no longer needed.

FWIW i did not hook that 5 volt feed up in my car, and my fuel gauge works perfectly

[driver456]

It is an extra 5 volt feed for the 97 fuel level sensor, now, you are retaining the 97 fuel sensors in your car but the way the new PCM will read your fuel level is different, so that 5 volt feed is no longer needed.

FWIW i did not hook that 5 volt feed up in my car, and my fuel gauge works perfectly

I was going to tell him to pm you because thats where I got my info from............Paul

[Adam Calley]

ok i see. well thanks for the info i really appreciate it thanks agian!!!