superstock

I have a 98 Formula but its hard to find any type of upgrade for any electronics.
My question is can you switch to a 99 or newer PCM and what it would take to do so. Thanks for any information.

flanders

iTrader: (1)

it has come to my attention that you may loose TCS/ASR fuctionality with this swap
how to swap a 98 f body pcm to a 99 f body pcm....

what you will need:
1.this list of wire changes to follow

2.7mm socket

3.5/16 battery wrench

4.a pair of vice grips

5.very small headed flat head screwdriver

6.LOTS of electrical tape

7.some sort of label maker (not required but very much recommended)

8.10 mm socket with extension.

9.razor blades or a razor knife.

10. misc small gauge wire, solder, wire strippers.

11. a/m fuel gauge. the reason for the new fuel gauge is honestly a mystery to me. if you install the signal wire and the out put wire the cluster just defaults the fuel gauge to full. (see bottom of write up)

11. oh and obviously your new pcm. now you don't HAVE to get an f-body pcm. The part# for the one you want is 9354896. This is the pcm for a 99-00 corvette, 99-00 f0body, 99-00 full size pick up with a v-8. These are pretty easy to pick up used and generally you won't have the core charge to deal with. If you buy a new one from a dealer you will be out the core because the pcm is shaped different and a sharp parts guy will not take it back as a core. (but don't worry about it looking different it will still slide into the pcm bracket.) If you do use a non f-body pcm then you will not be able to drive the car without downloading a stock tune for the year of the pcm. I don’t know if you will be able to use a HP tuners .bin file because you will have to change the vin in the pcm to program. So a dealer may be your only choice here but they will only charge an hour labor you just have to provide a vin for them to put in.

To start the first thing you want to do is disconnect the battery. There are at least 2 live wires that you will be messing with and a ton of grounds and you don't want to ruin any sensors or have your fans just come on because you grounded out a wire.
Next make some room to work with by removing the passenger side hood strut. Just open the hood and put the vice grips on the drivers side hood strut and use your small flat head to take the passenger side one off. Next unplug the 3 connectors on the pass fender to get some slack on the wires. Also pull the large harness away from the fire wall to get some more slack. You may also need to pull the harness that comes thru the fender loose for some more slack.
As you have probably noticed by now the pcm is mounted on the passenger side where the wheel well starts to dip back towards the fire wall. It is in its own little pocket and held in by 2 10mm bolts.
To remove the pcm first you want to get the 2 huge connectors off the top. these are held on by 7mm bolts. Just loosen these bolts and it will force the conn most of the way off the pcm. Pull them off and move them off to the side. Loosen the 2 10's for the pcm bracket. You will have to do some coaxing to get it out and also be very careful because there are a couple of vacuum lines on the left side of the bracket that you want to make sure you put back on if they come loose while removing and replacing the pcm.
Now that you have all this done you should have plenty of room to work with. Start to carefully remove the tape and conduit off the harnesses so you can expose the wires. To start to remove the wires out of the pcm terminals you will need to get the grey caps off the back of the connectors by using your small flat head to pry at the clips on the grey covers. Don't break these taking them off. Next you want to label the connectors. The one with the red caps is referred to as C-1 in this guide and the blue one is C-2. After you have labeled them you can take the red and blue caps off the connectors. TO do this use your small flat head again and starting from the bolt side push the little white tabs in and pull the caps off. If you happen to break any of the caps I am sure that you can get replacements but I don't know the part#'s. Also while you are playing with the harness ends you will notice the numbers all along the tops. These are your new friend for the next couple of hours.
Here is the list of what terminals to move where. I can't stress enough to pay very close attention to these because if you screw them up and don't have access to a scan tool you will hate life. The first time I rewired this I didn’t pay close enough attention and the car would run and not set the ses light but after I scanned it I had a **** ton of the weirdest codes you ever heard of.
Before you start yanking wires here is where the label maker comes in handy huge. Instead of just swapping the pins into the new spots label them so you can make up your own harnesses. If you don’t you will end up with one impossible harness that won't be able to plug back in let alone make look nice. To remove the pins from the connector just push the wire up from the back until you see the pin start to protrude from the white base and use your finger nail to pry out the little tab and carefully remove the wire and pin from the connector.
Now the pin movements PAY CLOSE ATTENTION!!!!!!!1!!


C-1 cavity 1 empty
C-1 cav 2 empty
C-1 cav 3 WHT goes to C-2 cav 45 evap canister vent sol valve control
C-1 cav 4 BRN/WHT goes to C-1 cav 73 cam pos sensor signal
C-1 cav 5-6 empty
C-1 cav 7 YEL goes to C-2 cav 21 VSS signal
C-1 cav 8 empty
C-1 cav 9 PNK/BLK goes to C-1 cav 3 inj #3 control
C-1 cav 10 empty
C-1 cav 11 DK BLU goes to C-2 cav 30 VTD fuel enable
C-1 cav 12 LT BLU/BLK goes to C-1 cav 44 inj 4 control
C-1 cav 13 RED/WHT goes to C-2 cav 67 ign control #2
C-1 cav 14 DK GRN goes to C-2 cav 18 a/c status signal
C-1 cav 15 BLK/WHT goes to C-1 cav 76 inj 5 control
C-1 cav 16-17 empty
C-1 cav18 YEL/BLK goes to C-1 cav 37 inj 6 control
C-1 cav 19-20 empty
C-1 cav 21 PPL goes to C-2 cav 57 IAT ground
C-1 cav 22 DK BLU goes to C-1 17 trans range signal B
C-1 cav 23 LT GRN/BLK goes to C-1 cav 4 inj 2 control
C-1 cav 24 BLK/WHT this is a ground jumper that is not needed the other end is C-2 cav 24 delete
C-1 cav 25 PNK goes to C-2 cav 63 trans range signal A
C-1 cav 26 empty
C-1 cav 27 RED/BLK goes to C-1 cav 43 inj 7 control
C-1 cav 28-29 empty
C-1 cav 30 GRY/BLK goes to C-2 cav 53 spark retard signal (this may not be there) I think that it is for traction control vehicles. don’t worry too much about it. if it is there move it.
C-1 cav 31 DK BLU/WHT goes to C-1 cav 77 inj 8 control
C-1 cav 32 ORN/BLK to C-1 cav 34 PNP switch signal
C-1 cav 33 BLK to C-1 cav 36 inj 1 control
C-1 cav 34 GRY for 6sp WHT for a4 to C-1 cav 79 skip shift sol or 2-3 shift sol
C-1 cav 35 LT GRN to C-2 cav 48 1-2 shift sol
C-1 cav 36 DK/BLU delete fuel gauge out put control
C-1 cav 37 BRN/WHT to C-2 cav 46 malfunction lamp control
C-1 cav 38 empty
C-1 cav 39 DK GRN/WHT to C-2 cav 43 a/c clutch relay
C-1 cav 40 WHT for 6sp YEL/BLK for a4 to C-2 cav 47 skip shift lamp or 2-3 shift sol
C-1 cav 41 BRN/WHT delete
C-1 cav 42 LT GRN to C-2 cav 44 6sp only reverse inhibit sol
C-1 cav 43 DK GRN to C-1 cav 42 engine cooling fan relay #1
C-1 cav 44 YEL to C-1 cav 12 crank pos sensor signal input
C-1 cav 45 DK GRN/WHT to C-2 cav 34 EVAP can purge valve control
C-1 cav 46 empty
C-1 cav 47 DK GRN/WHT to C-2 17 a/request signal
C-1 cav 48 YEL to C-2 cav 31 MAF signal
C-1 cav 49 PPL to C-2 cav 26 ignition 1 control
C-1 cav 50-51 empty
C-1 cav 52 PPL/WHT to C-2 cav 66 ignition 8 control
C-1 cav 53 RED to C-2 cav 27ignition 7 control
C-1 cav 54 LT BLU/WHT to C-2 cav 28 ignition 6 control
C-1 cav 55 DK GRN/WHT to C-2 cav 50 VSS output signal
C-1 cav 56 DK GRN to C-2 cav 68 ignition 5 control
C-1 cav 57 DK GRN/WHT to C-2 cav 29 ignition 4 control
C-1 cav 58 LT BLU to C-2 cav 69 ignition 3 control
C-1 cav 59 BRN/WHT to C-2 cav 61 ignition control ref low bank 2
C-1 cav 60 BRN to C-2 cav 60 ignition control ref low bank 1
C-1 cav 61 RED to C-1 cav 18 trans range signal C
C-1 cav 62 BLK to C-1 cav 41 EGR pintle position ground
C-1 cav 63 BLK this is a ground for the a/c refrigerant pressure sensor ground so you will just need to ground it out somewhere.
C-1 cav 64-70 empty
C-1 cav 71 PPL to C-2 cav 20 VSS ref low
C-1 cav 72 BLK to C-2 cav 1 PCM ground
C-1 cav 73-74 empty
C-1 cav 75 GRY to C-1 cav 23 fuel tank pressure sensor/ sender ground
C-1 cav 76 BLK to C-2 cav 40 PCM ground
C-1 cav 77 PPL to C-1 cav 33 TCC/brake switch signal
C-1 cav 78-80 empty

flanders

iTrader: (1)

C-2 cav 1 TAN to C-1 cav 25 O2 sensor signal low bank2 sensor2
C-2 cav 2 TAN/WHT to C-1 cav 28 O2 sensor signal low bank1 sensor2
C-2 cav 3 TAN delete
C-2 cav 4 RED to C-2 cav 39 cam position sensor B+ supply
C-2 cav 5 TAN to C-1 cav 26 O2 sensor low bank2 sensor1
C-2 cav 6 TAN/WHT to C-1 cav 29 O2 sensor low bank1 sensor1
C-2 cav 7 RED/BLK to C-2 cav 14 a/c refrigerant pressure sensor signal
C-2 cav 8 TAN to C-2 cav 25 IAT Sensor Signal In Pin B (added by mrvedit)
C-2 cav 9 BRN to C-1 cav 55 EGR printle position sensor signal
C-2 cav 10 PPL leave loose to hook to a/m gauge
C-2 cav 11 RED to C2 cav 15 Alternator "F" Turn On (added by mrvedit - may depend upon your Alternator type)
C-2 cav 12 DK BLU to C-2 cav 24 TP sensor signal
C-2 cav 13 YEL/BLK to C-2 cav 51 trans fluid temp sensor signal
C-2 cav 14 ORN/BLK to C-1 cav 53 trans fluid temp sensor ground
C-2 cav 15-18 empty
C-2 cav 19 PNK to C-1 cav 19 PCM IGN 1 feed
C-2 cav 20 ORN to C-1 cav 20 PCM battery feed
C-2 cav 21 BLK to C-1 cav 40 PCM ground
C-2 cav 22 YEL/BLK to C-1 cav 21 crank position sensor ref low
C-2 cav 23 BLK to C-1 cav 60 TP sensor ground
C-2 cav 24 see C-1 cav 24
C-2 cav 25 BRN to C-1 cav 80 engine coolant temp sensor ground
C-2 cav 26 ORN/BLK to C-1 cav 54 MAP sensor ground
C-2 cav 27 empty
C-2 cav 28 DK BLU to C-2 cav 33 cooling fan relay 2 and 3
C-2 cav 29 empty
C-2 cav 30 BRN to C-2 cav 36 AIR pump relay control
C-2 cav 31 PPL to C-2 cav 4 AIR solenoid relay control
C-2 cav 32 TAN/BLK to C-2 cav 42 TCC enable solenoid
C-2 cav 33 BRN to C-2 cav 2 TCC sol control valve
C-2 cav 34 GRY to C-2 cav 41 EGR valve ground
C-2 cav 35 WHT to C-2 cav 10 engine speed (tach) output signal
C-2 cav 36 LT BKU/WHT to C-2 cav 8 trans fluid pressure control solenoid control low
C-2 cav 37 DK GRN/WHT C-2 cav 9 fuel pump relay control
C-2 cav 38 LT BLU to C-2 cav 7 EGR control
C-2 cav 39 RED/BLK to C-2 cav 6 trans fluid pressure control solenoid control high
C-2 cav 40 empty
C-2 cav 41 PPL to C-1 cav 65 O2 signal high bank2 sensor 2
C-2 cav 42 PPL/WHT to C-1 cav 68 O2 high bank1 sensor1
C-2 cav 43 GRY to C-1 cav 8 TP sensor 5v reference
C-2 cav 44-45 empty
C-2 cav 46 PPL to C-1 cav 66 O2 signal high bank2 sensor1
C-2 cav 47 PPL/WHT to C-1 cav 69 O2 signal high bank1 sensor1
C-2 cav 48 LT GRN to C-2 cav 32 MAP sensor signal
C-2 cav 49 YEL to C-1 cav 74 engine coolant temp sensor signal
C-2 cav 50-51 empty
C-2 cav 52 DK GRN to C-2 cav 64 fuel tank pressure sensor signal
C-2 cav 53 empty
C-2 cav 54 LT GRN/BLK to C-2 cav 77 IAC coil B low
C-2 cav 55 LT BLU/BLK to C-2 cav 78 IAC coil A low
C-2 cav 56 LT BLU/WHT to C-2 cav 79 IAC coil A high
C-2 cav 57 LT GRN/WHT to C-2 cav 76 IAC coil B high
C-2 cav 58 PPL to C-1 cav 58 serial data
C-2 cav 59 empty
C-2 cav 60 BLK to C-1 cav 1 PCM ground
C-2 cav 61 ORN to C-1 cav 57 PCM batt feed
C-2 cav 62 LT GRN to C-1 cav 2 crankshaft position sensor B+ supply
C-2 cav 63 empty
C-2 cav 64 GRY to C-1 cav 48 MAP sensor 5v reference
C-2 cav 65 GRY to C-1 cav 47 EGR pintle position sensor 5v reference
C-2 cav 66 GRY to C-1 cav 45 a/c refrigerant pressure sensor 5v reference
C-2 cav 67 GRY to C-1 cav 46 fuel tank pressure sensor 5v reference
C-2 cav 68 LT BLU to C-1 cav 11 knock sensor rear
C-2 cav 69 DK BLU to C-1 cav 51 knock sensor front
C-2 cav 70 PNK/BLK to C-1 cav 61 camshaft position sensor low reference
C-2 cav 71-75 empty
C-2 cav 76 BRN to C-1 cav 70 oil level sensor signal
C-2 cav77-80 empty
Now you should have a whole **** ton of wires with flags. It is best to group them in C-1 and C-2 fashion so you have 2 separate harnesses. You will also notice that a few wires are really short. You need to lengthen them, preferably with the same color wire so you don't mix them up. I also strongly suggest that you solder and shrink wrap these splices (butt connectors and tape is not gonna get it).
Once you have 2 separate harnesses and are happy with the length of the wires star stabbing them in.
When you are done stabbing the wires in find your blue and red caps. Put the blue one on the connector you labeled C-1 and the red on C-2. Now before you go plugging the connectors on the PCM double check your work with the following list.
C-1 1 black
C-1 2 Lt green
C-1 3 PNK/BLK
C-1 4 LT GRN/BLK
C-1 5-7 empty
C-1 8 GRA
C-1 9-10 empty
C-1 11 LT BLU
C-1 12 YEL
C-1 13-16 empty
C-1 17 DK BLU
C-1 18 RED
C-1 19 PNK
C-1 20 ORN
C-1 21 YEL/BLK
C-1 22 EMPTY
C-1 23 GRA
C-1 24 EMPTY
C-1 25 TAN
C-1 26 TAN
C-1 27 EMPTY
C-1 28 TAN WHT
C-1 29 TAN'WHT
C-1 30-31 EMPTY
C-1 32 EMPTY if you have a 6sp you will set a code for P0704 clutch switch circuit. You need to shut this code off and put a grounded wire in the terminal.
C-1 33 PPL
C-1 34 ORN/BLK
C-1 35 EMPTY
C-1 36 BLK
C-1 37 YEL/BLK
C-1 38-39 EMPTY
C-1 40 BLK
C-1 41 BLK
C-1 42 DK GREEN
C-1 43 RED/BLK
C-1 44 LT BLU/BLK
C-1 45 GRA
C-1 46 GRA
C-1 47 GRA
C-1 48 GRA
C-1 49-50 EMPTY
C-1 51 DK BLU
C-1 52 EMPTY
C-1 53 ORN/BLK
C-1 54 ORN/BLK
C-1 55 BRN
C-1 56 EMPTY
C-1 57 ORN
C-1 58 PPL
C-1 59 EMPTY
C-1 60 BLK
C-1 61 PNK/BLK
C-1 62-64 EMPTY
C-1 65 PPL
C-1 66 PPL
C-1 67 EMPTY
C-1 68 PPL/WHT
C-1 69 PPL/WHT
C-1 70 BRN
C-1 71-72 EMPTY
C-1 73 BRN/WHT
C-1 74 YEL
C-1 75 EMPTY
C-1 76 BLK/WHT
C-1 77 DK BLU/WHT
C-1 78 EMPTY
C-1 79 GRA 6sp WHT a4
C-1 80 BRN

C-2 1 BLK
C-2 2 BRN
C-2 3 EMPTY
C-2 4 PPL
C-2 5 EMPTY
C-2 6 RED/BLK
C-2 7 LT BLU
C-2 8 LT BLU/WHT
C-2 9 DK GRN/WHT
C-2 10 WHT
C-2 11-12 EMPTY
C-2 13 EMPTY
C-2 14 RED/BLK
C-2 15-16 EMPTY
C-2 17 DK GRN/WHT
C-2 18 DK GRN
C-2 19 EMPTY
C-2 20 PPL
C-2 21 YEL
C-2 22-23
C-2 24 DK BLU
C-2 25 TAN
C-2 26 PPL
C-2 27 RED
C-2 28 LT BLU/WHT
C-2 29 DK GRN/WHT
C-2 30 DK BLU
C-2 31 YEL
C-2 32 LT GRN
C-2 33 DK BLU
C-2 34 DK GRN/WHT
C-2 35 EMPTY
C-2 36 BRN
C-2 37-38 EMPTY
C-2 39 RED
C-2 40 BLK
C-2 41 GRA
C-2 42 TAN/BLK
C-2 43 DK GRN/WHT
C-2 44 6sp TL GRN a4 EMPTY
C-2 45 WHT
C-2 46 BRN/WHT
C-2 47 YEL/BLK
C-2 48 LT GRN
C-2 49 EMPTY
C-2 50 DK GRN/WHT
C-2 51 YEL/BLACK
C-2 52 EMPTY
C-2 53 GRA.BLK
C-2 54-56 EMPTY
C-2 57 PPL
C-2 58-59
C-2 60 BRN
C-2 61 BRN/WHT
C-2 62 EMPTY
C-2 63 PNK
C-2 64 DK GRN
C-2 65 EMPTY
C-2 66 PPL/WHT
C-2 67 RED/WHT
C-2 68 DK GRN
C-2 69 LT BLU
C-2 70-75 EMPTY
C-2 76 LT GRN/WHT
C-2 77 LT GRN/BLK
C-2 78 LT BLU/BLK
C-2 79 LT BLU/WHT
C-2 80 EMPTY
After you are sure that the wires are correct plug the blue C-1 into the lower part of the pcm and the red C-2 into the upper end. Now you can slide the PCM into the bracket and fight the PCM and bracket back into its home.
Now it is just a matter of retaping all the harnesses you opened and putting every thing back.
This is a work in progress so don't call it a be all end all but I was very thorough not to make mistakes. The only code you should be left with when done is ( ) this is a generator L terminal code. It does not set an engine light and makes no difference. If you want to hear the long story PM me. Also don't forget the clutch code I already mentioned for the 6sp guys.
If anyone has any questions or suggestions please feel free to let me know.
Oh yeah don't forget to reconnect the battery for start up hehe.

The answer for the fuel gauge. You can purchase an auto meter 0-90 ohm gauge and send it in to them to get it set up for our cars you need 40 ohm empty and 250 ohm full. They charge like $25.00 and shipping.


Flanders

5_02ls1

iTrader: (20)

so you dont need the 99-up tank and lines and other things...maybe i was misinformed..i know the 98s use a regulator on the rails and a return and the 99 up cars regulate the pressure in the tank by increasing pump voltage.someone enlighten me on this im confused...

slow

iTrader: (7)

sorry, 98 f-cars do not use a front mount regulator and the rails are the same as the 1999-2002 cars.

all 1998-2002 f-cars use a in tank mounted regulator, and a loop i the back, with a T after the fuel filter. The T feeds the rails with a single line.

(Fords use a voltage based returnless fuel system like your describing, but they run a IPS/FRPS sensor on the rails)

Ryan

5_02ls1

iTrader: (20)

its amasing on how much false info can read on the net.i went out and looked at my rails and lines and the line i thought was a return goes to some sort of ssolenoid and then to the front of the manifold.i remember seeing the
loop after the filter when i done my gears as well.
what is the thing on the rails that looks like a regulator?you can see it in my sig pic...

98turbls1

iTrader: (17)

Great write up... This should definitely be STICKIED... I really need to do this to mine but I'm going to see how far I can get with a 2 Bar SD tune first....

5_02ls1

iTrader: (20)

i have been told numerous time all the fuel components were different..i know the tank is but looks like the rest is the same.this will definately be a future modafter actualy seeing some one do it. i hope some of the guys thatr mis informed me read this thread...

flanders

iTrader: (1)

i need a favor from someone with a 98 pcm to figure out the fuel gauge. question. I need to see if someone can ohm out the purple wire in connector 2 (the one with the blue cap) cavity 11 and the dark blue wire in cav 36 on connector 2 (the one with the red cap) with the key on and the connectors on the pcm. And what level your fuel gauge is presently at. I am trying to narrow down what the pcm does to the ohm signal on the purple wire to send the signal to the blue wire to the gauge.
thanks to anyone who can do this for me.
I think that i can come up with a solution so that you can still use the factory fuel gauge on the cluster.

Doc

iTrader: (9)

Why not just swap calibration segments?

flanders

iTrader: (1)

i know that i sound dumb but i don't know what you mean by that. i do know that in 98 the cluster recieved the signal direcly from the level sensor to the pcm to the cluster. in 99+ it traveled on the class 2 serial data line so there is no output signal spot on the 99+ pcm.

Runn

subscribing..

slow

iTrader: (7)

it is a pulse dampener, there is a good thread on eflive about how to use a express van calibration segment to work with the 98 fuel sender.

Ryan

flanders

iTrader: (1)

the pulse dampener on the fuel rail??

Eurospec2

iTrader: (2)

Just to simplify any answer, yes the PCM swap can be done, without changing any parts other then the PCM. No, there is no way to make traction control work (on F-Bodies, corvette traction control will still work just fine) after this swap without re-wiring pretty much the entire car.

Vetal

iTrader: (3)

Really you need to rewire that much to make TCS work?

Runn

I´ve heard that you should change the knocksensors for the ones used 99up.

Is it possible to use a 02pcm?

Vetal

iTrader: (3)

That's with EFI Live. But I already have my car HPT tuned, so my fuel gauge won't work, if I understand correctly

Vetal

iTrader: (3)

When buying 99-02 PCM, does it matter if car was auto or manual?

Eurospec2

iTrader: (2)

No, the hardware is all the same, just have the correct program loaded into it and you will be fine