Dead Opti???
Thread Starter
8th Gear
Joined: Mar 2007
Posts: 8
Likes: 0
Dead Opti???
I have a 95 vette that left me walking one day. After I got it home I tried to run the codes. I got a 16 so I changed the distributor, and also the ignition module. I now have spark ,something that was lacking before. But--- it still fails to crank up. I can get it to fire maybe four no more than five times and after that it just turns over. I also checked the fuel pressure and it checked good. This thing is driving me crazy any help any one can give me would be greatly appreciated.
Thanx,
Rob
Thanx,
Rob
Thread Starter
8th Gear
Joined: Mar 2007
Posts: 8
Likes: 0
I appreciate your rapid response, I am currently trying to come up with a different way to download the trouble codes in the ECM. I was using software and a laptop but still telling me the same as it did before. So when I get that done I'll post them.
Thanx Again.
Bob
Thanx Again.
Bob
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Here you go Bob, get your paper clip out and follow my chart mate. The codes listed at the bottom are for Module 4
On a 94/95 you can check the codes with a paper clip as follows:
You short pin "12" to pin "4" and turn the ignition switch to "On" without starting the engine.
The speedometer will display any codes using the same protocol as the 1990-1993 model but there are some changes in the designation for the modules plus additional modules are added:
Module "1" is still the CCM module.
Module "4" is now called the PCM module (Powertrain Control Module) because automatic transmission computer control was added to Engine Control Module in 1994.
Module 7 (on the 1996 model only) is the RTD module. (This is the Real Time Dampening module which replaced the Selective Ride Control module in 1996).
Module 9 is the ABS/ASR module number from 1994 through 1996.
Finally, Module "A", the DERM (Dynamic Energy Control Module --- (the air bag control module) will be requested to show any codes.
Just like the 1990-1993 display, you read the codes on the speedometer (big) and read the module number on the trip odometer (small).
A series of dashed lines for instance “ - - -“ indicates no more stored codes for that module.
A code showing as “C12” for the CCM module (module #1) means no codes are stored. So C12 is a good thing to see.
Again, you can cause the codes to repeat by turning the ignition off for five seconds and then back on.
Turn the ignition off and remove the short to restore normal operation.
To clear the codes,
1. With ignition "off" ground terminal #12 of the DLC (use bent paper clip to connect pin 4 to pin 12)
2. Turn ignition "on".
3. Press trip/odo button on the DIC until 1.7 appears in the trip
monitor area of the instrument cluster.
4. Press eng/met button on the DIC & hold until "---" appears in the
speedometer area of the cluster, this will clear CCM DTC'S.
To clear PCM/ECM codes do the following:
1. Press the trip reset button on the DIC until the desired system is displayed. In this case it will be 4.0.
2. Press trip/odo button on the DIC until the desired diagnostic mode(4.7) is displayed on the trip monitor area of the cluster.
3. Press & hold the eng/met button on the DIC until "---" is
displayed in the speedometer area of the cluster, this will clear PCM codes.
To clear ABS/ASR codes do the following:
Same as above but you’re looking for “9.7” on the trip odo
And here are the codes
1994-1995: Diagnostic Trouble Codes
DTC #11: Malfunction Indicator Lamp Circuit.
DTC #13: Bank #1 Heated Oxygen Sensor #1 Circuit:
DTC #14: Engine Coolant Temperature Sensor Circuit Voltage Low.
DTC #15: Engine Coolant Temperature Sensor Circuit Voltage High.
DTC #16: Distributor Ignition System Low Pulse.
DTC #18: Injector Circuit.
DTC #21: Throttle Position Sensor Circuit Voltage High.
DTC #22: Throttle Position Sensor Circuit Voltage Low.
DTC #23: Intake Temperature Sensor Circuit Voltage High.
DTC #24: Vehicle Speed Sensor Circuit.
DTC #25: Intake Air Temperature Sensor Circuit Voltage Low.
DTC #26: Evaporative Emission Canister Purge Solenoid Valve Circuit.
DTC #27: EGR Vacuum Control Signal Solenoid Valve Circuit.
DTC #28: Transmission Range Pressure Switch Assembly Fault.
DTC #29: Secondary Air Injection Pump Circuit.
DTC #32: Exhaust Gas Recalculation.
DTC #33: Manifold Absolute Pressure Sensor Circuit High.
DTC #34: Manifold Absolute Pressure Sensor Circuit Low.
DTC #36: Distributor Ignition System High Pulse.
DTC #37: Brake Switch Stuck On.
DTC #38: Brake Switch Stuck Off.
DTC #41: Ignition Control Circuit Open.
DTC #42: Ignition Control Circuit Shorted.
DTC #43: Knock Sensor Circuit.
DTC #44: Bank 1 LF Heated Oxygen Sensor #1 Circuit Lean.
DTC #45: Bank 1 LF Heated Oxygen Sensor #1 Circuit Rich.
DTC #47: Knock Sensor Circuit Or Module Missing.
DTC #48: Mass Air Flow Sensor Circuit.
DTC #50: System Voltage Low.
DTC #51: EPROM Programming Error.
DTC #52: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #53: System Voltage Low.
DTC #55: Fuel Lean Monitor.
DTC #58: Transmission Fluid Temperature Sensor Circuit Low.
DTC #59: Transmission Fluid Temperature Sensor Circuit High.
DTC #62: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #63: Bank 2 RF Heated Oxygen Sensor #1 Circuit Open.
DTC #64: Bank 2 RF Heated Oxygen Sensor #1 Circuit Lean.
DTC #65: Bank 2 RF Heated Oxygen Sensor #1 Circuit Rich.
DTC #66: A/C Refrigerant Pressure Sensor Circuit Open.
DTC #67: A/C Pressure Sensor Circuit Sensor or A/C Clutch.
DTC #68: A/C Relay Circuit.
DTC #69: A /C Clutch Circuit.
DTC #70: A/C Clutch Relay Driver Circuit.
DTC #72: Vehicle Speed Sensor Loss.
DTC #73: Pressure Control Solenoid Circuit Current Error.
DTC #74: Traction Control System Circuit Low.
DTC #75: Transmission System Voltage Low
DTC #77: Primary Cooling Fan Relay Control Circuit.
DTC #78: Secondary Cooling Fan Relay Control Circuit.
DTC #79: Transmission Fluid Overtemp.
DTC #80: Transmission Component Slipping.
DTC #81: Transmission 2-3 Shift Solenoid Circuit.
DTC #82: Transmission 1-2 Shift Solenoid Circuit.
DTC #83: Torque Converter Solenoid Voltage High.
DTC #84: 3-2 Control Solenoid Circuit.(Auto Only).
DTC #84: 2nd And 3rd Gear Blockout Relay Control Circuit.
DTC #85: Transmission TCC Stock On.
DTC #90: Transmission TCC Solenoid Circuit.
DTC #91: One To Four Upshift Lamp(Manual Only).
DTC #97: VSS Output Circuit.
DTC #98: Tachometer Output Signal Voltage Wrong.
On a 94/95 you can check the codes with a paper clip as follows:
You short pin "12" to pin "4" and turn the ignition switch to "On" without starting the engine.
The speedometer will display any codes using the same protocol as the 1990-1993 model but there are some changes in the designation for the modules plus additional modules are added:
Module "1" is still the CCM module.
Module "4" is now called the PCM module (Powertrain Control Module) because automatic transmission computer control was added to Engine Control Module in 1994.
Module 7 (on the 1996 model only) is the RTD module. (This is the Real Time Dampening module which replaced the Selective Ride Control module in 1996).
Module 9 is the ABS/ASR module number from 1994 through 1996.
Finally, Module "A", the DERM (Dynamic Energy Control Module --- (the air bag control module) will be requested to show any codes.
Just like the 1990-1993 display, you read the codes on the speedometer (big) and read the module number on the trip odometer (small).
A series of dashed lines for instance “ - - -“ indicates no more stored codes for that module.
A code showing as “C12” for the CCM module (module #1) means no codes are stored. So C12 is a good thing to see.
Again, you can cause the codes to repeat by turning the ignition off for five seconds and then back on.
Turn the ignition off and remove the short to restore normal operation.
To clear the codes,
1. With ignition "off" ground terminal #12 of the DLC (use bent paper clip to connect pin 4 to pin 12)
2. Turn ignition "on".
3. Press trip/odo button on the DIC until 1.7 appears in the trip
monitor area of the instrument cluster.
4. Press eng/met button on the DIC & hold until "---" appears in the
speedometer area of the cluster, this will clear CCM DTC'S.
To clear PCM/ECM codes do the following:
1. Press the trip reset button on the DIC until the desired system is displayed. In this case it will be 4.0.
2. Press trip/odo button on the DIC until the desired diagnostic mode(4.7) is displayed on the trip monitor area of the cluster.
3. Press & hold the eng/met button on the DIC until "---" is
displayed in the speedometer area of the cluster, this will clear PCM codes.
To clear ABS/ASR codes do the following:
Same as above but you’re looking for “9.7” on the trip odo
And here are the codes
1994-1995: Diagnostic Trouble Codes
DTC #11: Malfunction Indicator Lamp Circuit.
DTC #13: Bank #1 Heated Oxygen Sensor #1 Circuit:
DTC #14: Engine Coolant Temperature Sensor Circuit Voltage Low.
DTC #15: Engine Coolant Temperature Sensor Circuit Voltage High.
DTC #16: Distributor Ignition System Low Pulse.
DTC #18: Injector Circuit.
DTC #21: Throttle Position Sensor Circuit Voltage High.
DTC #22: Throttle Position Sensor Circuit Voltage Low.
DTC #23: Intake Temperature Sensor Circuit Voltage High.
DTC #24: Vehicle Speed Sensor Circuit.
DTC #25: Intake Air Temperature Sensor Circuit Voltage Low.
DTC #26: Evaporative Emission Canister Purge Solenoid Valve Circuit.
DTC #27: EGR Vacuum Control Signal Solenoid Valve Circuit.
DTC #28: Transmission Range Pressure Switch Assembly Fault.
DTC #29: Secondary Air Injection Pump Circuit.
DTC #32: Exhaust Gas Recalculation.
DTC #33: Manifold Absolute Pressure Sensor Circuit High.
DTC #34: Manifold Absolute Pressure Sensor Circuit Low.
DTC #36: Distributor Ignition System High Pulse.
DTC #37: Brake Switch Stuck On.
DTC #38: Brake Switch Stuck Off.
DTC #41: Ignition Control Circuit Open.
DTC #42: Ignition Control Circuit Shorted.
DTC #43: Knock Sensor Circuit.
DTC #44: Bank 1 LF Heated Oxygen Sensor #1 Circuit Lean.
DTC #45: Bank 1 LF Heated Oxygen Sensor #1 Circuit Rich.
DTC #47: Knock Sensor Circuit Or Module Missing.
DTC #48: Mass Air Flow Sensor Circuit.
DTC #50: System Voltage Low.
DTC #51: EPROM Programming Error.
DTC #52: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #53: System Voltage Low.
DTC #55: Fuel Lean Monitor.
DTC #58: Transmission Fluid Temperature Sensor Circuit Low.
DTC #59: Transmission Fluid Temperature Sensor Circuit High.
DTC #62: Engine Oil Temperature Sensor Circuit Voltage Low.
DTC #63: Bank 2 RF Heated Oxygen Sensor #1 Circuit Open.
DTC #64: Bank 2 RF Heated Oxygen Sensor #1 Circuit Lean.
DTC #65: Bank 2 RF Heated Oxygen Sensor #1 Circuit Rich.
DTC #66: A/C Refrigerant Pressure Sensor Circuit Open.
DTC #67: A/C Pressure Sensor Circuit Sensor or A/C Clutch.
DTC #68: A/C Relay Circuit.
DTC #69: A /C Clutch Circuit.
DTC #70: A/C Clutch Relay Driver Circuit.
DTC #72: Vehicle Speed Sensor Loss.
DTC #73: Pressure Control Solenoid Circuit Current Error.
DTC #74: Traction Control System Circuit Low.
DTC #75: Transmission System Voltage Low
DTC #77: Primary Cooling Fan Relay Control Circuit.
DTC #78: Secondary Cooling Fan Relay Control Circuit.
DTC #79: Transmission Fluid Overtemp.
DTC #80: Transmission Component Slipping.
DTC #81: Transmission 2-3 Shift Solenoid Circuit.
DTC #82: Transmission 1-2 Shift Solenoid Circuit.
DTC #83: Torque Converter Solenoid Voltage High.
DTC #84: 3-2 Control Solenoid Circuit.(Auto Only).
DTC #84: 2nd And 3rd Gear Blockout Relay Control Circuit.
DTC #85: Transmission TCC Stock On.
DTC #90: Transmission TCC Solenoid Circuit.
DTC #91: One To Four Upshift Lamp(Manual Only).
DTC #97: VSS Output Circuit.
DTC #98: Tachometer Output Signal Voltage Wrong.
Thread Starter
8th Gear
Joined: Mar 2007
Posts: 8
Likes: 0
Dead Opti?
I ran the codes like you said and got something like this:
Module 1 H41
Module 4 H74
Module 9 H64
After I wrote all that down I cleared the codes and now I have nothing. Boy this is tough! Where do I go from here. I had hoped one of the sensors was taking it out, but no codes. Thanks Again for all the help you don't know how much I appreciate it
Thanx,
Bob
Module 1 H41
Module 4 H74
Module 9 H64
After I wrote all that down I cleared the codes and now I have nothing. Boy this is tough! Where do I go from here. I had hoped one of the sensors was taking it out, but no codes. Thanks Again for all the help you don't know how much I appreciate it
Thanx,
Bob
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
No worries mate, ill just grab the service manual and tell you what the modules 1 and 9 codes are.
At this stage id check the terminals on your battery, make sure they are nice and clean, make sure your battery isnt dead, and check all the ground connections.
At this stage id check the terminals on your battery, make sure they are nice and clean, make sure your battery isnt dead, and check all the ground connections.
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Ok,
Module 1 DTC 41 is: Loss of PCM serial data comunications
Module 9 DTC 64 is: Throttle position signal malfunction
Id say youve got a bad connection there somewhere, either at the CCM or the PCM, a bad ground connection, or a bad connection at the battery.
Module 1 DTC 41 is: Loss of PCM serial data comunications
Module 9 DTC 64 is: Throttle position signal malfunction
Id say youve got a bad connection there somewhere, either at the CCM or the PCM, a bad ground connection, or a bad connection at the battery.
Thread Starter
8th Gear
Joined: Mar 2007
Posts: 8
Likes: 0
dead opti???
I have since checked all the terminals and the battery is being jumped off my Geo. What I did find was when you run a compression check the pressure bleeds down. Thats strange because when I brought it up on #1 it only had like 40 PSI. Ijust discounted it to an old guage but now I wonder. I tried it on my Geo and it doesn't bleed down. Please tell me what you think.
Thanx,
Bob
Thanx,
Bob
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Thread Starter
8th Gear
Joined: Mar 2007
Posts: 8
Likes: 0
Dead Opti?
Hi There, A friend at work told me it could be the timing chain jumped time so this week I will change the timing gears and see what that does. As soon as I find out anything I will post as to how it's going.
Adios for now,
Bob
Adios for now,
Bob
Thread Starter
8th Gear
Joined: Mar 2007
Posts: 8
Likes: 0
Dead Opti?
I have about 65000 on the clock. He said they still the old nylon edged timing gears and they fail at about that mileage. I'm about half done changing them so we'll see ifthat will make it run
Thanx,
Bob
Thanx,
Bob
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Yeah? Who told him that? Im just a shade under 100,000 miles and havent replaced mine yet, they aint failed or jumped either. Youll have to show us a picture of them when you get them out!!! 
Safety Car
Joined: Apr 2003
Posts: 3,793
Likes: 9
From: VA
All it takes is fuel, spark, and compression. You say you have spark, and compression may be bad. Do you have fuel at the plugs?
You also have failed components indicated by the trouble codes you pulled. Why are you throwing other parts at it instead of fixing those?
Thread Starter
8th Gear
Joined: Mar 2007
Posts: 8
Likes: 0
dead opti??
Welll, I have since checked the timing gears. They look brand new. I am getting really close to raising the white flag on this one. Maybe the ECM Throttle position sensor. I've got a friend with a shop and he wants me to bring it over there, but Ive done so much on it already I hate to pay somebody else especially to do something I can do if I just knew what it was
Thanx,
Bob
Thanx,
Bob
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
If you had spark and fuel pressure, I willing to bet you might have installed the spline gear on the opti wrong on the cam. Even if your off 2 teeth it may not start. The opti should almost fall on the gear with ease and hit the cover with a ting, and be flush. You should not have to tighten the bolts to bring it in to the cover.
It looks like it can’t be done but many have installed it incorrectly many times. Get the cam notch up, and match it to the gear and slide it on.
Then start the car with no water pump to make sure it runs. You need to put on MAF and attach water pump temp sensor. The wires will reach, just lay on top. After it runs, put it back together. Best of luck.
It looks like it can’t be done but many have installed it incorrectly many times. Get the cam notch up, and match it to the gear and slide it on.
Then start the car with no water pump to make sure it runs. You need to put on MAF and attach water pump temp sensor. The wires will reach, just lay on top. After it runs, put it back together. Best of luck.
Thread Starter
8th Gear
Joined: Mar 2007
Posts: 8
Likes: 0
dead opti??
This is for all the people out there that was so helpful. I just wanted you to know that I changed the ECM but the instructions said it had to be reprogrammed at the dealer. They did and I am now back on the road again.
One more thought I bought a rebuilt computer from Auto Parts Giant and one of the pins was broke and the dealer had to use my old one. I have contacted Auto Parts Giant for the last week and a half and nothing. Be advised before you deal with them.
Thanks Again,
Rob
One more thought I bought a rebuilt computer from Auto Parts Giant and one of the pins was broke and the dealer had to use my old one. I have contacted Auto Parts Giant for the last week and a half and nothing. Be advised before you deal with them.
Thanks Again,
Rob
