effects of an ESC module???

[dyeager535]

According to the Camaro manual, yes the ESC module is separate, but not something you can bypass, as the ECM tests it's operation.

Cars and trucks were both using the '7747 ECM, those did not have the onboard (part of the ECM) ESC. Neither did TPI until 1990.

 

[LEEREED123]

Uhh ... this module by the master ... does it, by chance, say "K-H" on it?

I'm thinking you have a 1990-91 truck, which has (lame) antilock brakes, which would be the module on the brake system.

Post up a pic... and also the code you're getting. Could be the antilock and they're crap ;D

-- A

no,no. not the abs..... (although, that doesn't work either, brake light stays on)
what I ment was mine is mounted on the master cylinder side of my intake....
it definately is the ESC module.

 

[LEEREED123]

Here's your info on the circuit and how to troubleshoot it: http://www.thirdgen.org/techboard/tech-general-engine/240876-need-know-where-knock.html?highlight=maf+esc

Pretty basic, it's the knock sensor control.

THANKS FOR THE INFO!

 

[Blue85]

From my understadning...an esc hei dist has a 7pin module...the way i did it was unplugged the harness for the coil from the 7pin module removed the 7pin module from dist and unhooked it from the pickup coil. (green and yellow wire)

Then in my case i have MSD, so i used their magnetic p/u thingy that replaces all of this, if you have, or can get a 5or 4 pin module simply plug the coil harness and the pickup coil into it and you've bypassed the ESC.

I can get pics too if anybody wants them...ive got a spare dist and harnesses...

someone correct me if im wrong though...

4-pin = full dizzy control of timing (no knock sensor)
5-pin = ESC - external spark retard line (trucks only)
7-pin = ECM timing control

The 5-pin can be replaced by a 4-pin to ditch the ESC system

 

[Thunder]

You can not bypass a TBI 7 pin module and still have the timing work right and not have trouble code(s) set.

The ECM looks for function of the ESC. First when you start up the engine and later after it has reached operating temp. The ECM checks for ESC operation by advancing the timing untill knocking is picked up by the knock sensor . The ESC should should then retard timing untill no knock is detected.
If timing is advanced fully and no knocking is picked up ( possibly bad knock sensor). Or pinging does not stop (Bad ESC?). The ECM sets a code 43. When that code is set the ECM will not allow the timing to advance fully to prevent pinging and engine damage.
The engine will run normally but will not get full advance timing. This condition will affect fuel milage and performance.

The only way to fully bypass ESC in TBI is to have it programed out of the chip.

If you do have a code 43 which means a problem with the ESC circut. Check to make sure all the wireing is plugged in right. Make sure the knock sensor is plugged in
A bad knock sensor will set a 43.
If you replace the knock sensor be sure not to use thread sealant or teflon tape. The KS needs a solid connection to the block.
Check above stuff before replacing the ESC module.
These things are why it is good to have a good scanner or winALDL to diagnose problems.
You would be able to see the knock sensor operating or not if you had a scanner.

 

[LEEREED123]

You would be able to see the knock sensor operating or not if you had a scanner.

yeah, but I have a tech 1 GM scanner, it won't show me that.( that I know of)

 

[dyeager535]

I believe the TBI ECM's (and early TPI) don't allow you to monitor spark timing very well. I know on mine, the scanner automatically bumps the idle to 1000RPM. I thought that it did something to timing as well, but I can't remember what. I don't think it "locks out" the knock sensor, as I could see knock counts in winALDL.