codes?
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Before I went chasing any of these items and do any extensive troubleshooting, I would clear the codes and see if they return. Make sure they are in module 4. Make sure the connector is on the air temp sensor, resistance can be measured at a later time.
Thread Starter
Pro
Joined: Feb 2006
Posts: 543
Likes: 0
From: powhatan va.
yes i cleared the codes before i went out to drive itand those were the only two codes in it when i can back. i have been having this problem of the car cutting off while im going down the road. sometimes it refires right away then sometimes it takes a couple of tries. i sent my ignition box off to get checked because i thought it might be that, but they sent it back saying no defects found. the opti sound in line with the problem and code but i will do some more dia. before i change anything. is there anyway to check the opti without removing it? thanks for your help.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
I am going to guess that when you say your ignition box, you are referring to the ECM (big silver box, under hood drivers side, 4 connectors). ECMs have all kinds of weird problems and a bench test might reveal nothing. Substituting may be the only way to diagnose this problem.
The high resolution pulse from the opti can actually be measured with an oscilloscope if you tap into the right wire at the opti. Most people will not have the right equipment or know-how to pull this off and would not recommend it to most. However, loosing this pulse should not kill the engine. Pulse is used for timing advance and crank shaft position.
As far as the air temp code, you can check out sensor and wiring. Not a real common code. But ECM can be reading it wrong, or produce a code on its own.
No way to tell why car is cutting off going down road. But all these symptoms can be related back to a bad ECM.
A lot of this is opinion, not many hard facts to go on.
The high resolution pulse from the opti can actually be measured with an oscilloscope if you tap into the right wire at the opti. Most people will not have the right equipment or know-how to pull this off and would not recommend it to most. However, loosing this pulse should not kill the engine. Pulse is used for timing advance and crank shaft position.
As far as the air temp code, you can check out sensor and wiring. Not a real common code. But ECM can be reading it wrong, or produce a code on its own.
No way to tell why car is cutting off going down road. But all these symptoms can be related back to a bad ECM.
A lot of this is opinion, not many hard facts to go on.
Racer
Joined: Nov 2007
Posts: 449
Likes: 0
From: Warren, Michigan
these might help. read thru this thread.
http://www.c4guru.com/articles/CCMCodePull.pdf
Code Description
13 Left Oxygen Sensor Open
14 Coolant Temp High
15 Coolant Temp Low
16 OptiSpark Low Resolution (Fuel)
21 TPS Signal Voltage High
22 TPS Signal Voltage Low
23 Intake Air Temp Low
24 Vehicle Speed Sensor
25 Intake Air Temp High
26 Quad Driver 1
27 Quad Driver 2
28 Quad Driver 3
32 EGR (Valve and/or Circuit)
33 MAP Voltage High (Low Vacuum)
34 MAP Voltage Low (High Vacuum)
36 OptiSpark High Resolution (Timing)
41 EST (Knock Sensor) Error
Code Description
42 EST (Knock Sensor) Grounded
43 EST (Knock Sensor) Circuit Error
44 Left Oxygen Sensor Lean
45 Left Oxygen Sensor Rich
51 MEM-CAL (ECM Chip) Error
52 Engine Oil Temp Sensor (Low Temp)
53 System Voltage Error
55 Fuel Lean Monitor
62 Engine Oil Temp Sensor (High Temp)
63 Right Oxygen Sensor Open
64 Right Oxygen Sensor Lean
65 Right Oxygen Sensor Rich
66 A/C Pressure Sensor Error
67 A/C Pressure Sensor or Clutch Error
68 A/C Relay Error
69 A/C Clutch Circuit
72 Gear Selector Switch Error
http://www.c4guru.com/articles/CCMCodePull.pdf
Code Description
13 Left Oxygen Sensor Open
14 Coolant Temp High
15 Coolant Temp Low
16 OptiSpark Low Resolution (Fuel)
21 TPS Signal Voltage High
22 TPS Signal Voltage Low
23 Intake Air Temp Low
24 Vehicle Speed Sensor
25 Intake Air Temp High
26 Quad Driver 1
27 Quad Driver 2
28 Quad Driver 3
32 EGR (Valve and/or Circuit)
33 MAP Voltage High (Low Vacuum)
34 MAP Voltage Low (High Vacuum)
36 OptiSpark High Resolution (Timing)
41 EST (Knock Sensor) Error
Code Description
42 EST (Knock Sensor) Grounded
43 EST (Knock Sensor) Circuit Error
44 Left Oxygen Sensor Lean
45 Left Oxygen Sensor Rich
51 MEM-CAL (ECM Chip) Error
52 Engine Oil Temp Sensor (Low Temp)
53 System Voltage Error
55 Fuel Lean Monitor
62 Engine Oil Temp Sensor (High Temp)
63 Right Oxygen Sensor Open
64 Right Oxygen Sensor Lean
65 Right Oxygen Sensor Rich
66 A/C Pressure Sensor Error
67 A/C Pressure Sensor or Clutch Error
68 A/C Relay Error
69 A/C Clutch Circuit
72 Gear Selector Switch Error
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
Your code 36 and the car dying are probably related to the Opti. Check under the WP weep hole see if any coolant is leaking there. You haven't washed your engine have you? That is a sure Opti killer. There is no way to check the opti other than rule out other causes. Check the FSM for the proper diagnostic steps. Good luck
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Thread Starter
Pro
Joined: Feb 2006
Posts: 543
Likes: 0
From: powhatan va.
is there anything besides the opti that might through the opti code? just trying to narrow it down, like anything before the signal gets to the opti. other than the ecm. hope that makes sense lol.
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
Nope the opti has a circular plate in it with 360 slots for high resolution and I forget how many for low resolution (8 I think someone can correct me on this). The 360 is for timing purposes and equates to the rotation of the crank. I say this with a caveat though if the ECM does not see FOR ANY REASON the counts it will toss the code. I guess it could be a wiring issue but 99% of the time it is rust or contamination on the plate.
Racer
Joined: Sep 2007
Posts: 393
Likes: 0
From: Bartonville Illinois
The 36 code can also be set if the ECM doesn't see the right number of pulses when it counts the high res and compares it to low res. It needs to count 60 pulses between each low res pulse.
If you checked the pulses with an oscilloscope the only thing you can really see is that there are pulses there and their amplitude. It should be 5 volts.
I replaced my opti a while back. The rotor was dirty and the cap was corroded badly. I haven't checked the CCM yet but Datamaster is indicating a code 36 with the brand new opti. The books say if the counts aren't correct 5 times in a row it sets the code. This may be an indication that the counter circuits in the ECM are not functioning properly.
The Optispark is a very poor design but my car was running very good with the old dirty cap and rotor until I decided to wash the motor down a bit before reading the forum.
There is also a test connector between the ECM and the Opti, its under the fuel rail cover (Passenger side) you might clean this connector and the one at the opti itself.
Good luck.
If you checked the pulses with an oscilloscope the only thing you can really see is that there are pulses there and their amplitude. It should be 5 volts.
I replaced my opti a while back. The rotor was dirty and the cap was corroded badly. I haven't checked the CCM yet but Datamaster is indicating a code 36 with the brand new opti. The books say if the counts aren't correct 5 times in a row it sets the code. This may be an indication that the counter circuits in the ECM are not functioning properly.
The Optispark is a very poor design but my car was running very good with the old dirty cap and rotor until I decided to wash the motor down a bit before reading the forum.
There is also a test connector between the ECM and the Opti, its under the fuel rail cover (Passenger side) you might clean this connector and the one at the opti itself.
Good luck.