I have some engine problems. Help!!

[UB2 SLOW]

Alright, I keep getting the 0132, 0152 and 0300 codes. They come and go as they please. The latest problem is that the car seems to buck and sputter above 40mph occasionaly and if I keep driving it keeps getting worse and seems like it wants to back fire. It dosent throw any codes when it does this either which I cant undertand.

Here is the Autotap for the codes.

Check Engine Light: ON

Time Since Codes Cleared: ---
Distance Since Codes Cleared: ---
Drive Cycles Since Codes Cleared: ---

Confirmed Diagnostic Trouble Codes:
Code: Description:
P0132 HO2S Circuit High Voltage Bank 1 Sensor 1
P0152 HO2S Circuit High Voltage Bank 2 Sensor 1
P0300 Random/Multiple Cylinder Misfire Detected

Possible Diagnostic Trouble Codes:
Code: Description:

--------: EMISSION TEST STATUS :--------
Emission Status: <SELECT DATE>
Vehicle Model Year: <SELECT>

OBD Compliant: Yes
Misfire Monitoring: Complete
Heated Catalyst Monitoring: Not Supported
Comprehensive Component Monitoring: Complete
Catalyst Monitoring: Complete
Fuel System Monitoring: Complete
Evaporative System Monitoring: Not Supported
Secondary Air System Monitoring: Complete
EGR System Monitoring: Complete
Oxygen Sensor Monitoring: Complete
Oxygen Sensor Heater Monitoring: Complete
A/C System Refrigerant Monitoring: Not Supported

--------: FREEZE FRAME DATA :--------
Generated by DTC code: P0300

Fuel System Status Bank 1: CL-1
Calculated Engine Load: 12.2 %
Engine Coolant Temperature: 181 °F
Short Term Fuel Trim Bank 1: 0 %
Long Term Fuel Trim Bank 1: -1.6 %
Short Term Fuel Trim Bank 2: 0 %
Long Term Fuel Trim Bank 2: -1.6 %
Manifold Absolute Pressure (MAP): 11.8 in Hg
Engine Speed: 2217 RPM
Vehicle Speed: 26 MPH
Mass Air Flow Rate: 3.948 lb/min
Throttle Position Angle: 6.7 %

 

[Hib Halverson]

Questions:
1) Has this problem existed since you installed the LT4?
2) If so, is the cal in the ECM for LT4 or LT1?
3) Have you attempted to solve the codes with the information in the factory service manual?

 

[UB2 SLOW]

Answers
1) No
2) Dont know? Jeff at Carolina Auto Masters did the tune. What would be the difference? I am going to buy the LT1 Edit or Tuner Cat. I have not decided yet. I am also worried that I mess something up.
3) So far no luck on using the manual. It seems like I try something and the codes go away, but eventually come back. My biggest concern is that the car has started bucking and stumbling. It starts above 40mph and 30 minutes.

Thanks for the quick reply.

 

[jmccloud]

Stumble warm at cruise speed

I've had similar symptoms on 3 GM cars (fortunately not the Corvette). They would buck and stumble only after warm up, especially in the 40-50mph range and really bad if in overdrive, cruise control on and beginning up a hill.
The first one cost me $100 at the dealer to find it was one bad plug wire. The load of high gear and uphill caused a slight misfire until the transmission kicked out of overdrive, then all was well. All of the cars were automatics but the same symptoms could occur with a manual in higher gear.
The other two GM cars got an immediate spark wire set for a lot less than $100. Problem gone.
My son had a Grand Prix that misbehaved similarly and it was a bad coil (that 3.8L uses 3 coils and 'lost spark').
Those cars also caused visible interference on my TV when it was tuned to a weaker analog antenna channel.
Hope this helps

 

[C4Tom]

I would definately check out all plugs and plug wires.

You would be amazed at the effects of 1 cylinder dropping out under load. One of which is a nasty bucking.

 

[UB2 SLOW]

I just did a test my told be about. He said to tune my car radio to a AM channel that was not playing music. He said then drive the car and if the static noise matches the revs of the engine I have a bad wire or wires. Well it matched. I just placed an order for some new MSD wires. I hope this fixes it.

 

[Robertwav1]

That seems like a great start...even if it doesn't solve the problem you can move on. Cheers