does a 91 have a spark control module?
Le Mans Master
Joined: Oct 2000
Posts: 6,362
Likes: 30
From: Oak Harbor WA
Re: does a 91 have a spark control module? (cesar)
On my 93 LT1 it is located on the passenger side head attached to the coil assy. Kind of tucked under the heater hoses and behind the power steering resevoir. Good luck...
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Yes, your L98 does. It is located underneath the rotor inside the distributor. Pop off the wires (note locations first), disconnect the 3 connectors, and grab a 1/4" socket. Remove the 4 holddown bolts on the cap and pull it off. The rotor can be removed by undoing the two screws on it. The control module is the small black thing with 3 connects on it (2 on one end, 1 on the other). There should be 7 pins on it if it is like mine.
If you install a new one remember remember remember to put the dilectric grease on the metal plate side of the new module to help dissipate heat.
If you install a new one remember remember remember to put the dilectric grease on the metal plate side of the new module to help dissipate heat.
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
43 is the knock sensor. Check to see if the wire has come off of it. It is located down on the block near the starter on the passenger side. Round shaped thing with a wire harness plugged into it.
Le Mans Master
Joined: Oct 2000
Posts: 6,362
Likes: 30
From: Oak Harbor WA
Re: (scorp508)
Thanks for correcting me Scorp. I should have remembered that from my HEI days.
Oh, if you end up removing the knock sensor, DO NOT put thread sealant on the sensor. It only has one wire because it grounds out to the block. Trace wire back to the source and once again, good luck.
Oh, if you end up removing the knock sensor, DO NOT put thread sealant on the sensor. It only has one wire because it grounds out to the block. Trace wire back to the source and once again, good luck.
Burning Brakes
Joined: Feb 2000
Posts: 824
Likes: 2
From: Camden SC
Re: (Goody)
The knock sensor is connected to the ESC, Electronic Spark Control module.
The item under the distributor cap is the electronic ignition module and works with the ECM to control spark timing.
The ESC module for the 91, I believe it's the same as the 90, is located on the passenger side below the A/C blower, faces outside, somewhere around there. Square looking thing and should have around five wires on a connector.
EST, Eletronic Spark Timing, is the 7 pin ignition module (thing under the cap) and ECM/computer controlled timing.
ESC DOES communicate with the ECM via one wire (8-10 volts), circuit 485, should be a black wire.
A code 43 is for the ESC, knock sensor/ESC. It means the ECM has read low voltage along circuit 485 for more than 4 seconds or ESC failed an operational check.
The factory service manual has an excellent discussion of this located on the Code 43 page. Look around section 6E3-A-62. If you do not have the factory service manaul, sell your spare tire, borrow some money, whatever, and you will be pleased. IF you are not happy, I will buy it from you.
Hope you get the car fixed.
dlmeyers 90 coupe zf6 3 speed shocks
[Modified by dlmeyers, 5:31 PM 10/27/2002]
The item under the distributor cap is the electronic ignition module and works with the ECM to control spark timing.
The ESC module for the 91, I believe it's the same as the 90, is located on the passenger side below the A/C blower, faces outside, somewhere around there. Square looking thing and should have around five wires on a connector.
EST, Eletronic Spark Timing, is the 7 pin ignition module (thing under the cap) and ECM/computer controlled timing.
ESC DOES communicate with the ECM via one wire (8-10 volts), circuit 485, should be a black wire.
A code 43 is for the ESC, knock sensor/ESC. It means the ECM has read low voltage along circuit 485 for more than 4 seconds or ESC failed an operational check.
The factory service manual has an excellent discussion of this located on the Code 43 page. Look around section 6E3-A-62. If you do not have the factory service manaul, sell your spare tire, borrow some money, whatever, and you will be pleased. IF you are not happy, I will buy it from you.
Hope you get the car fixed.
dlmeyers 90 coupe zf6 3 speed shocks
[Modified by dlmeyers, 5:31 PM 10/27/2002]
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Racer
Joined: May 2001
Posts: 252
Likes: 0
From: VillaPark,IL U.S.A. IL
Re: (cesar)
Disconnect the knock sensor and ohm it out. It should be 4.3k ohms.
Thier is no esc module on the 91 cars. It is controllered in the memcal.
Chuck MacTrinder
#72 http://www.tccracing.com
Thier is no esc module on the 91 cars. It is controllered in the memcal.
Chuck MacTrinder
#72 http://www.tccracing.com
Burning Brakes
Joined: Feb 2000
Posts: 824
Likes: 2
From: Camden SC
Re: (cesar)
OOPpppssss, big hit on me.
The 91 ZR1 has the module. The 91 L98 has the ESC function as part of the MEM Cal prom. Sorry about that. Spent some time with the ZR's at Carlisle, the box just sits right near the blower. It was just in my head. Sorry about that. Didn't mean to cause you a lot of heartache.
The code 43 for the VIN8 cars will set when voltage hits between 3.62 volts and 1.44 volts on circuit 496. Single wire out of the knock sensor, then off to the ECM.
The knock sensor is the most likely culprit unless you have problems with timing or some ESC module problems. Clear the code and note if it comes on during heavy acceleration or other times. Let us know. Did you reset any timing lately?
Once again, sorry I gave you the stuff for the ZR1.
Hope it gets fixed.
dlmeyers 90 coupe zf6 3 speed shocks
The 91 ZR1 has the module. The 91 L98 has the ESC function as part of the MEM Cal prom. Sorry about that. Spent some time with the ZR's at Carlisle, the box just sits right near the blower. It was just in my head. Sorry about that. Didn't mean to cause you a lot of heartache.
The code 43 for the VIN8 cars will set when voltage hits between 3.62 volts and 1.44 volts on circuit 496. Single wire out of the knock sensor, then off to the ECM.
The knock sensor is the most likely culprit unless you have problems with timing or some ESC module problems. Clear the code and note if it comes on during heavy acceleration or other times. Let us know. Did you reset any timing lately?
Once again, sorry I gave you the stuff for the ZR1.
Hope it gets fixed.
dlmeyers 90 coupe zf6 3 speed shocks
