Car is running funny, threw some codes
Thread Starter
TECH Enthusiast
Joined: Sep 2009
Posts: 565
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From: Decatur, IN
Car is running funny, threw some codes short story car was running great, did a 70-120 pull on the highway late at night coming home from a car show
right has i was getting ready to let off, the SES light came on and i slowed back down to 70 mph, then the car hesitated and and felt like it lost a lot of power when ever i tried to accelerate, i kept my foot off the gas and made it home by driving very lightly on the throttle
scanned the car and thew both left and right 02 sensor codes, cleared the codes, now the car runs a TINY bit better, not as much hesitation and kinda (jerky) throttle responce but still seems like its running about 3/4 of the power it was making
since i cleared the codes the SES light hasnt came back on but like I said the car feels like its on about 75% power than it was a week ago
I was just going to order both new 02 sensors, and new spark plugs, and do an oil change
what would yall suggest may be the problem/solution?
right has i was getting ready to let off, the SES light came on and i slowed back down to 70 mph, then the car hesitated and and felt like it lost a lot of power when ever i tried to accelerate, i kept my foot off the gas and made it home by driving very lightly on the throttle
scanned the car and thew both left and right 02 sensor codes, cleared the codes, now the car runs a TINY bit better, not as much hesitation and kinda (jerky) throttle responce but still seems like its running about 3/4 of the power it was making
since i cleared the codes the SES light hasnt came back on but like I said the car feels like its on about 75% power than it was a week ago
I was just going to order both new 02 sensors, and new spark plugs, and do an oil change
what would yall suggest may be the problem/solution?
Could be just about anything... Do you have a scan tool?
Start with the basics:
- O2 performance (are the O2s moving quickly, or are they lazy?)
- Misfires (are you getting a report of misfire(s)?)
- Sensors (are any other sensors throwing codes, but not turing on the ses light)
Kinda pointless to do plugs if its just a bad or loose wire. Better of doing some diag before just replacing stuff. Once its fixed, or if you determine the plugs to be bad, then replace them.
Start with the basics:
- O2 performance (are the O2s moving quickly, or are they lazy?)
- Misfires (are you getting a report of misfire(s)?)
- Sensors (are any other sensors throwing codes, but not turing on the ses light)
Kinda pointless to do plugs if its just a bad or loose wire. Better of doing some diag before just replacing stuff. Once its fixed, or if you determine the plugs to be bad, then replace them.
Thread Starter
TECH Enthusiast
Joined: Sep 2009
Posts: 565
Likes: 0
From: Decatur, IN
Could be just about anything... Do you have a scan tool?
Start with the basics:
- O2 performance (are the O2s moving quickly, or are they lazy?)
- Misfires (are you getting a report of misfire(s)?)
- Sensors (are any other sensors throwing codes, but not turing on the ses light)
Kinda pointless to do plugs if its just a bad or loose wire. Better of doing some diag before just replacing stuff. Once its fixed, or if you determine the plugs to be bad, then replace them.
Start with the basics:
- O2 performance (are the O2s moving quickly, or are they lazy?)
- Misfires (are you getting a report of misfire(s)?)
- Sensors (are any other sensors throwing codes, but not turing on the ses light)
Kinda pointless to do plugs if its just a bad or loose wire. Better of doing some diag before just replacing stuff. Once its fixed, or if you determine the plugs to be bad, then replace them.
Were the code for the front or rear O2's? The front can effect A/F ratio & the rears are emissions only. If the O2's are going bad & not supplying the PCM with correct signals it can effect performance.
I'd say replace & upgrade to Vette O2's while your at it. Plugs might not be needed but for the cost & minimal amount of time it takes to change them might as well. Same thing with a oil change if it's needed.
If no other codes were showing then you should notice a good improvement after replacing the O2's. I'd also check your fuel pressure. Could also be a weak pump which could cause a lean condition which the O2's would pick up on as well. Grab a gauge & hook it to the rail & check pressure with the key "ON" and while running. If it's a gauge you can see from inside the car also take it for a drive & see what it does under load during acceleration. That'll tell ya if it's a pump or not.
I'd say replace & upgrade to Vette O2's while your at it. Plugs might not be needed but for the cost & minimal amount of time it takes to change them might as well. Same thing with a oil change if it's needed.
If no other codes were showing then you should notice a good improvement after replacing the O2's. I'd also check your fuel pressure. Could also be a weak pump which could cause a lean condition which the O2's would pick up on as well. Grab a gauge & hook it to the rail & check pressure with the key "ON" and while running. If it's a gauge you can see from inside the car also take it for a drive & see what it does under load during acceleration. That'll tell ya if it's a pump or not.
Thread Starter
TECH Enthusiast
Joined: Sep 2009
Posts: 565
Likes: 0
From: Decatur, IN
Were the code for the front or rear O2's? The front can effect A/F ratio & the rears are emissions only. If the O2's are going bad & not supplying the PCM with correct signals it can effect performance.
I'd say replace & upgrade to Vette O2's while your at it. Plugs might not be needed but for the cost & minimal amount of time it takes to change them might as well. Same thing with a oil change if it's needed.
If no other codes were showing then you should notice a good improvement after replacing the O2's. I'd also check your fuel pressure. Could also be a weak pump which could cause a lean condition which the O2's would pick up on as well. Grab a gauge & hook it to the rail & check pressure with the key "ON" and while running. If it's a gauge you can see from inside the car also take it for a drive & see what it does under load during acceleration. That'll tell ya if it's a pump or not.
I'd say replace & upgrade to Vette O2's while your at it. Plugs might not be needed but for the cost & minimal amount of time it takes to change them might as well. Same thing with a oil change if it's needed.
If no other codes were showing then you should notice a good improvement after replacing the O2's. I'd also check your fuel pressure. Could also be a weak pump which could cause a lean condition which the O2's would pick up on as well. Grab a gauge & hook it to the rail & check pressure with the key "ON" and while running. If it's a gauge you can see from inside the car also take it for a drive & see what it does under load during acceleration. That'll tell ya if it's a pump or not.
i dont think the car has rear O2 sensors? just the two that are on the longtubes? I could be wrong though
and yes the plugs havent been changed in a few years, and the oil needs changed anyways
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