Codes?
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From: Manchester NH
Codes?
My 92 coupe takes forever to start, keeps cranking, crappy idle, hiccups. From what ive read sounds like typical opti problems. I pulled codes 15,16 and 42....i read code 16 is optispark low pulse. Is code 42 (EST circuit grounded) also Opti related? sure sounds like it.
Please bear with me...ive had the car 5 days and it only ran good for about the first 2 hours of ownership
Please bear with me...ive had the car 5 days and it only ran good for about the first 2 hours of ownership
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From: Manchester NH
I cant keep the car running..it takes a few tries to get it running and when it does fire i have to feather the gas to keep it running. It runs for maybe a minute if im lucky. If I give it to much it dies, not enough it dies. . Its going in the shop monday( I dont have the facilities or practical knowledge to repair myself) I did not reset the codes and I cant see a leak.
Thank you for the reply
Thank you for the reply
Le Mans Master
Joined: Jan 2006
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From: Orlando FL
Before going off the deep end with the opti, I agree to verify the current codes. If you were really missing the low resolution pulse, I wouldn’t think the engine would even run because it times the whole ignition as well as the injectors.
My first thought is that it could be a fuel delivery problem. I would at least get the fuel pressure checked to eliminate (or not) that factor. Then if the pressure is good you could look toward the ignition system.
Sounds stupid but a gas gauge problem might make you think there is gas in the tank, but its empty. Just a thought, seen it happen.
Off hand the symptom does not sound like a classic opti problem. Any chance you knocked off a connector or plug somewhere while checking. I would also check for a good spark and see if you can pull about a ½" spark from a plug wire or coil wire.
My first thought is that it could be a fuel delivery problem. I would at least get the fuel pressure checked to eliminate (or not) that factor. Then if the pressure is good you could look toward the ignition system.
Sounds stupid but a gas gauge problem might make you think there is gas in the tank, but its empty. Just a thought, seen it happen.
Off hand the symptom does not sound like a classic opti problem. Any chance you knocked off a connector or plug somewhere while checking. I would also check for a good spark and see if you can pull about a ½" spark from a plug wire or coil wire.
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From: Manchester NH
Thats interesting you mention the fuel gauge. when i picked the car up it had a half a tank. I drove it for 1 1/2 hours home with no problems. The next day it had 3/4 tank and my problems began. Now it says the tanks full...it also will start then die right away sometimes and other times it will just turn over and not fire
Last edited by jm22876; Jul 6, 2008 at 01:37 PM.
Le Mans Master
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From: Orlando FL
The fuel gauges do not work as the older cars from the 60 or 70s. A corroded or open sending unit would cause the gauge to read lower or just go to empty. On the newer cars like to corvette where the analog world meets the digital world, A lot of the cars electronics work digitally as so does the fuel gauge.
The gauge resistance works in reverse in regard to a full tank. Low resistance makes the gauge go lower and higher resistance makes it show a fuller tank. The sending unit normal operating resistance is approximately 20 to 110 ohms. The CCM sees this resistance and then drives the gauge indicator. When it does not see this resistance or a high value, the gauge reading can be anywhere.
The short of it is to add 5 gallons of gas and see if it runs. The long of it is to remove the sending unit and check it with a ohm meter.
The gauge resistance works in reverse in regard to a full tank. Low resistance makes the gauge go lower and higher resistance makes it show a fuller tank. The sending unit normal operating resistance is approximately 20 to 110 ohms. The CCM sees this resistance and then drives the gauge indicator. When it does not see this resistance or a high value, the gauge reading can be anywhere.
The short of it is to add 5 gallons of gas and see if it runs. The long of it is to remove the sending unit and check it with a ohm meter.
Last edited by pcolt94; Jul 6, 2008 at 09:44 PM.
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From: Manchester NH
It worked ...i put fuel in and it fired. It idled well, i took it around the block and sitting at a stoplight it wanted to die. I had to put it in neutral to keep it running. I pulled the negative side of the battery for 30 seconds to clear the codes. When i crossed a and b it came back with no codes. But when I crossed a and g i got:
Module 1 nothing
Module 4 nothing
module 7: Err
module 9:H35 LR wheel speed sensor error
H62 tachometer data error
I realize H means history...they stay in the ccm even if I cleared the codes.
Module 1 nothing
Module 4 nothing
module 7: Err
module 9:H35 LR wheel speed sensor error
H62 tachometer data error
I realize H means history...they stay in the ccm even if I cleared the codes.
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Safety Car
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From: :45 minutes from everywhere / E-I-E-I-O
It worked ...i put fuel in and it fired. It idled well, i took it around the block and sitting at a stoplight it wanted to die. I had to put it in neutral to keep it running. I pulled the negative side of the battery for 30 seconds to clear the codes. When i crossed a and b it came back with no codes. But when I crossed a and g i got:
Module 1 nothing
Module 4 nothing
module 7: Err
module 9:H35 LR wheel speed sensor error
H62 tachometer data error
I realize H means history...they stay in the ccm even if I cleared the codes.
Module 1 nothing
Module 4 nothing
module 7: Err
module 9:H35 LR wheel speed sensor error
H62 tachometer data error
I realize H means history...they stay in the ccm even if I cleared the codes.
And I think also all codes get cleared when the battery is off - don't they???
ed.: if the ig module is suspect, you can have it tested free and Advance / Zone stores..........
Last edited by schrade; Jul 7, 2008 at 10:18 PM.
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From: Manchester NH
I should clarify
It was 90 degrees here today...around the block where i live is about 3 miles with 3 sets of lights and a rotary. The coolant got to 203...Is closed loop when the thermostat opens? i.e 195?
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From: :45 minutes from everywhere / E-I-E-I-O
Some codes actually would trip before closed loop - I was wrong about that part.
Melting Slicks
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From: 1993 Quasar Blue 'vert Scottsdale AZ
No, it will go into closed loop way before that (unless you're running long-tube headers without heated O2 sensors). Have your ICM tested. IMHO, that's what it sounds like.
Le Mans Master
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From: Orlando FL
It worked ...i put fuel in and it fired. It idled well, i took it around the block and sitting at a stoplight it wanted to die. I had to put it in neutral to keep it running. I pulled the negative side of the battery for 30 seconds to clear the codes. When i crossed a and b it came back with no codes. But when I crossed a and g i got:
Module 1 nothing
Module 4 nothing
module 7: Err
module 9:H35 LR wheel speed sensor error
H62 tachometer data error
I realize H means history...they stay in the ccm even if I cleared the codes.
Module 1 nothing
Module 4 nothing
module 7: Err
module 9:H35 LR wheel speed sensor error
H62 tachometer data error
I realize H means history...they stay in the ccm even if I cleared the codes.
It goes into closed loop at approximately 125*. One of 3 conditions for closed loop operation.
As for the idle problem, I would check out the IAC (idle speed control motor). They can cause all kinds of idle problems. If it runs strong probably not a fuel pressure or flow problem. So if this is true, then focus on the idling. Might want to clean out the throttle body, can cause weird idling also.
Also take a peek at the EGR valve when the engine is cold. Push the door with your fingers just to make sure it moves OK and it is not stuck slightly open.
Last edited by pcolt94; Jul 8, 2008 at 10:43 AM.
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From: Manchester NH
Ignition control module
I went to 2 different autozones to try to get the icm tested...one didnt have the right connector and the other one said they didnt do it. I called 2 other autozones but no luck. Should i just order one? It starts now but still takes a 5 seconds to fire. How does the ICM control ignition?
Le Mans Master
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From: Orlando FL
Here is the basic bare bones plain language of what the ICM does. It is basically an amplifier, that’s it. It takes a 5 p-p volt square wave pulse from the ECM and amplifiers it to approximately 70 volts p-p which drives the primary of the ignition coil.
The reason for the ICM is because the ECM can not put out enough AC (drive)voltage to drive the coil at the power required.
It is a solid state amplifier which runs hot and can quit, become intermittent or have a low output at any time. Hence the coil does not get proper drive and the spark suffers.
Then the coil which is a step up transformer (like any other I coil), steps up the secondary voltage to 25K volts.
Oh yes, the older cars with the points and condenser. This acted as a switch to pulse the coil which required less input by design. And the output was only about 15K volts.
“It starts now but still takes a 5 seconds to fire. How does the ICM control ignition?”
The ICM does not control ignition, the ECM controls it and it does what its told.
5 seconds to start could be a dozen things or nothing. I personally would not look to the ECM first as a cause. I would look at fuel pressure for starters, plugs or wires.
Sometimes mine spins for a few seconds also but runs real well
Happy Motoring
The reason for the ICM is because the ECM can not put out enough AC (drive)voltage to drive the coil at the power required.
It is a solid state amplifier which runs hot and can quit, become intermittent or have a low output at any time. Hence the coil does not get proper drive and the spark suffers.
Then the coil which is a step up transformer (like any other I coil), steps up the secondary voltage to 25K volts.
Oh yes, the older cars with the points and condenser. This acted as a switch to pulse the coil which required less input by design. And the output was only about 15K volts.
“It starts now but still takes a 5 seconds to fire. How does the ICM control ignition?”
The ICM does not control ignition, the ECM controls it and it does what its told.
5 seconds to start could be a dozen things or nothing. I personally would not look to the ECM first as a cause. I would look at fuel pressure for starters, plugs or wires.
Sometimes mine spins for a few seconds also but runs real well
Happy Motoring
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Have you confirmed any codes?
The advance auto machine tester didn't have any type of connector adapter. They use tiny alligator clips - red lead on pin 1, grey on 2, green on 4, and black on the mounting ground that the screw goes into. The diagram for the connector is U7 on their chart. There's 2 U7 diagrams too - watch!
The advance auto machine tester didn't have any type of connector adapter. They use tiny alligator clips - red lead on pin 1, grey on 2, green on 4, and black on the mounting ground that the screw goes into. The diagram for the connector is U7 on their chart. There's 2 U7 diagrams too - watch!