check engine flashes on and off.. Bad mis
Thread Starter
Safety Car
Joined: Mar 2001
Posts: 4,383
Likes: 10
From: Kentucky
check engine flashes on and off.. Bad mis
Driving home in th erain tonight. Car was running fine.
Suddenly the motor has a mis. And the check engine light flases on and off...
Car has a terrible mis and hardly runs.
Codes P0153, P0803 C2120...
But I suspect that these codes are not telling me the problem as the car shoots them all the time.
I cleared the codes and the car still has a horrible mis but doesn't re-shoot the codes.
Anyone know whats up?
Suddenly the motor has a mis. And the check engine light flases on and off...
Car has a terrible mis and hardly runs.
Codes P0153, P0803 C2120...
But I suspect that these codes are not telling me the problem as the car shoots them all the time.
I cleared the codes and the car still has a horrible mis but doesn't re-shoot the codes.
Anyone know whats up?
Melting Slicks
Joined: May 2003
Posts: 3,494
Likes: 0
From: McKinney Tx
Cruise-In V Veteran
St. Jude's Donor '05
None of those codes have anything to do with your mis. I would definitely check your plug wires resistance levels and then check to make sure you dont have a cracked plug.
Good luck and let us know
Good luck and let us know
Safety Car
Joined: Sep 2001
Posts: 4,411
Likes: 1
From: Wilmington NC
Originally Posted by Red5
Driving home in th erain tonight. Car was running fine.
Suddenly the motor has a mis. And the check engine light flases on and off...
Car has a terrible mis and hardly runs.
Codes P0153, P0803 C2120...
But I suspect that these codes are not telling me the problem as the car shoots them all the time.
I cleared the codes and the car still has a horrible mis but doesn't re-shoot the codes.
Anyone know whats up?
Suddenly the motor has a mis. And the check engine light flases on and off...
Car has a terrible mis and hardly runs.
Codes P0153, P0803 C2120...
But I suspect that these codes are not telling me the problem as the car shoots them all the time.
I cleared the codes and the car still has a horrible mis but doesn't re-shoot the codes.
Anyone know whats up?
Thread Starter
Safety Car
Joined: Mar 2001
Posts: 4,383
Likes: 10
From: Kentucky
Originally Posted by Richin Chicago
These codes were for a bad skip shift reading, a bad O2 sensor reading, and a bad tire pressure monitor reading. Keep checking the codes to see if anything else shows up. Make sure you notice if the code has an "H" or "HC" suffix. With the current lack of codes I would start looking at spark plug wires. Do you have headers? They love to eat plug wires.
Thanks guys. It is nice that this many Corvette guys offer good advice.
All the codes ar HC.
It is still pouring down rain and do to a work in process I have going on in the garage, the vette is out in the rain.
So I will check the plug wires tom. It would be nice if this becaomes an easy fix.Only work on the vette has been a re-flash of the pcm via LS1edit yesterday. But I don't think that is realated either.
Team Owner
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From: Here
Pilot of Beer Force 1
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I believe in the Beer Fairy
either a plug wire went bad....arcing on a header...
or as in my case a plug actually backed out of the hole a bit causing a bad misfire, surging etc.
I have no idea how this happened but it did...I would recommend pulling each wire and plug individually and checking the wires for cracks etc..mine cracked thru the boot so...check the wires with an Ohm meter.....don't worry about specific values so much as making sure they are all consistent...trust me you will know which one is bad...just a little something I did last time I replaced my wires....save 2 of the best old ones....I just had a brand new wire fail and I was damn glad I kept an old one...at $60 a set I didnt want to be buying a set for 1 damn wire.
Good luck..
or as in my case a plug actually backed out of the hole a bit causing a bad misfire, surging etc.
I have no idea how this happened but it did...I would recommend pulling each wire and plug individually and checking the wires for cracks etc..mine cracked thru the boot so...check the wires with an Ohm meter.....don't worry about specific values so much as making sure they are all consistent...trust me you will know which one is bad...just a little something I did last time I replaced my wires....save 2 of the best old ones....I just had a brand new wire fail and I was damn glad I kept an old one...at $60 a set I didnt want to be buying a set for 1 damn wire.
Good luck..
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Melting Slicks
Joined: Jun 2004
Posts: 3,439
Likes: 6
From: Newark, DE
St. Jude Donor '06
From my '04 Owner Manual, re flashing Check Engine:
The following may prevent more serious damage to your vehicle:
* Reducing vehicle speed.
* Avoiding hard accellerations.
* Avoiding steep uphill grades.
If the light stops flashing and remains on steady, see "If the Light is On Steady" following. [Note: "steady" is an indication of emission control system malfunction. It can also be the result of wet ignition or bad fuel.]
If the light continues to flash, when it is safe to do so, stop the vehicle. Find a safe place to park your vehicle. Turn the key off, wait at least 10 seconds and restart the engine. If the light remains on steady, see "If the Light is On Steady." If the light is still flashing, follow the previous steps, and see your dealer for service as soon as possible.
This doesn't tell you much that you didn't already know... just offered FWIW. As for the codes...
P0153 = Heated Oxygen Sensor (HO2S) Slow Response Bank 2 Sensor 1
P0803 = 1-4 Upshift Solenoid Control Circuit (M/T)
C2120 = TPM System Malfunction (No Sensors Received)
HTH!
- Light Flashing — A misfire condition has been detected. A misfire increases vehicle emissions and may damage the emission control system on your vehicle. Diagnosis and service may be required.
The following may prevent more serious damage to your vehicle:
* Reducing vehicle speed.
* Avoiding hard accellerations.
* Avoiding steep uphill grades.
If the light stops flashing and remains on steady, see "If the Light is On Steady" following. [Note: "steady" is an indication of emission control system malfunction. It can also be the result of wet ignition or bad fuel.]
If the light continues to flash, when it is safe to do so, stop the vehicle. Find a safe place to park your vehicle. Turn the key off, wait at least 10 seconds and restart the engine. If the light remains on steady, see "If the Light is On Steady." If the light is still flashing, follow the previous steps, and see your dealer for service as soon as possible.
This doesn't tell you much that you didn't already know... just offered FWIW. As for the codes...
P0153 = Heated Oxygen Sensor (HO2S) Slow Response Bank 2 Sensor 1
P0803 = 1-4 Upshift Solenoid Control Circuit (M/T)
C2120 = TPM System Malfunction (No Sensors Received)
HTH!
Melting Slicks
Joined: Jun 2004
Posts: 3,439
Likes: 6
From: Newark, DE
St. Jude Donor '06
Originally Posted by Red5
I think I am going to buy a new set of wires and plugs...
GL!
P.S. When it's fixed, install a hood seal. If the problem is water related, it may prevent a recurrence (can't hurt, and only costs ~$12).
Thread Starter
Safety Car
Joined: Mar 2001
Posts: 4,383
Likes: 10
From: Kentucky
Originally Posted by BW1
Probably a good place to start.
GL!
P.S. When it's fixed, install a hood seal. If the problem is water related, it may prevent a recurrence (can't hurt, and only costs ~$12).
GL!
P.S. When it's fixed, install a hood seal. If the problem is water related, it may prevent a recurrence (can't hurt, and only costs ~$12).
Will do.
Racer
Joined: Oct 2001
Posts: 483
Likes: 0
From: Downingtown PA
Assuming you're running headers, I vote for the number 7 plug wire and yes, it's the one that's the biggest pita to get to. Even with the best fire sleeves, the heat generated at the track will eventually get to the #7 wire.
Melting Slicks
Joined: May 2003
Posts: 3,494
Likes: 0
From: McKinney Tx
Cruise-In V Veteran
St. Jude's Donor '05
Originally Posted by 01C5fan
Assuming you're running headers, I vote for the number 7 plug wire and yes, it's the one that's the biggest pita to get to. Even with the best fire sleeves, the heat generated at the track will eventually get to the #7 wire.
Racer
Joined: Dec 2000
Posts: 339
Likes: 2
From: West Hartford, CT, USA
Originally Posted by 01C5fan
Assuming you're running headers, I vote for the number 7 plug wire and yes, it's the one that's the biggest pita to get to. Even with the best fire sleeves, the heat generated at the track will eventually get to the #7 wire.
Thread Starter
Safety Car
Joined: Mar 2001
Posts: 4,383
Likes: 10
From: Kentucky
And the Survey Says:
BROKEN VALVE SPRINGS!
Just changed all of them. #1 and #3 had bad springs. #1` was broke in two places. These are the COMP 918 Springs.
Switched to Patriot Gold springs. Let's see how they do.
It was odd that the spring gave up when driving slow.
See if I ever drive the vette slow again. 
BROKEN VALVE SPRINGS!
Just changed all of them. #1 and #3 had bad springs. #1` was broke in two places. These are the COMP 918 Springs.
Switched to Patriot Gold springs. Let's see how they do.
It was odd that the spring gave up when driving slow.
See if I ever drive the vette slow again.
