p0300,p0700.p1781 2004 aveo

Hello working on a 2004 aveo with the 1.6 auto trans, I have code p0300, p0700,p1781


Anyone here mess with an aveo with these 3 codes..it drives good but no 4th gear.. engine is smooth and no shakes or vibes, it starts up fine, no stalls
think its the crank or cam sensor.. this is also what the dealership thinks..
but i have heard could be other issues.. any ideas?


P0300 DTC P0300

SYSTEM DESCRIPTION
The engine control module (ECM) uses information from the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor in order to determine when an engine misfire is occurring. By monitoring variations in the crankshaft rotation speed for each cylinder, the ECM is able to detect individual misfire events. A misfire rate that is high enough can cause overheating and damage to the 3-way catalytic converter (TWC) under certain driving conditions. The malfunction indicator lamp (MIL) will flash ON and OFF when the conditions for TWC damage are present. If the ECM detects a misfire rate sufficient to cause emission levels to exceed a predetermined value, DTC P0300 sets.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0300 Engine Misfire Detected

CONDITIONS FOR RUNNING THE DTC
- DTCs P0106, P0107, P0108, P0117, P0118, P0122, P0123, P0315, P0336, P0337, P0341, P0342, and P0502 are not set.
- The engine speed is between 600-6,500 RPM and steady.
- The ignition 1 voltage is between 11-16 volts.
- The engine coolant temperature (ECT) is between -7°C and 120°C (19°F and 248°F).
- The fuel level is more than 15 percent.
- The throttle angle is steady within 4 percent.
- The antilock brake system (ABS) and the traction control system (TCS), if equipped, is not active.
- The torque management is not active.
- The transmission is not changing gears.
- The A/C clutch is not changing states.
- The ECM is not in fuel shut-off or decel fuel cut-off mode.
- The ECM is not receiving a rough road signal.
- DTC P0300 runs continuously when the above conditions are met.

CONDITIONS FOR SETTING THE DTC
The ECM detects a crankshaft rotation speed variation indicating a misfire sufficient to cause emission levels to exceed a predetermined value.

ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.

DIAGNOSTIC AIDS
Excessive vibration from sources other than the engine could cause DTC P0300 to set. The following are possible sources of vibration:
- A tire or wheel that is out of round or out of balance
- Variable thickness brake rotors
- A unbalanced or damaged driveline condition
- Certain rough road conditions
- Worn or damaged accessory drive component or belt

p1781
DTC P1781

Conditions for Setting the DTC
^ Transmission control module (TCM) detects that malfunction of engine speed signal for 2 seconds
^ No DTC U2105

Action Taken When the DTC Sets
^ TCM will request the illumination of the malfunction indicator lamp (MIL) and store the DTC when the TCM detects a failure on the 1st ignition cycle
^ No engine torque reduction control
^ No lock-up
^ No engagement pressure control
^ No 4th gear
^ No self-learning control
^ No timing solenoid control for N-D
^ TCM judges the engine revolution is 0 RPM

Conditions for Clearing the DTC
^ The TCM turns OFF the MIL when no further failures are detected on the next ignition cycles.
^ The scan tool can clear the DTC from the TCM history.
^ The TCM clears the DTC from the TCM history memory after 40 consecutive ignition cycles without fault.

p0700

DTC P0700

CIRCUIT DESCRIPTION
This diagnostic trouble code (DTC) indicates that an emission related transmission DTC set in the transmission control module (TCM). The engine control module (ECM) receives the TCM DTC information over the serial data circuit. The ECM turns ON the malfunction indicator lamp (MIL) when the TCM sends a message over the serial data circuit requesting MIL illumination. The ECM will also store the freeze frame/failure records data for a transmission DTC. The DTC information for the ECM will only display DTC P0700, but the freeze frame/failure records data will display the transmission DTC that set.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0700 Transmission Control Module (TCM) Requested MIL Illumination

CONDITIONS FOR RUNNING THE DTC
DTC P0700 runs continuously

CONDITIONS FOR SETTING THE DTC
The ECM receives a serial data message, from the TCM, in order to illuminate the MIL.

ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.

TEST

anyoneout there, dealer says the valves are bad

i can see that is a really long thought out post.

i would suggest checking the coil pack.

a few ways to check it would be pulling the cover off the engine and misting the coil pack and wires with water while it is running.. and watch for a light show, it helps to do this in the dark/shade. If the dealership is doing it for you, tell them to try swapping it out.

I had these codes. I changed my plugs and wires.

I recently had my engine swapped from an 04 to an 07. Car feels great when driving but I am getting p1781, p0455, p0700. Had compression test and it came back good. Is it possible the the ecm is freaking out because of the engine swap?

|So what did you find out?

I had the exact same problem. Chevy Aveo 2004, 4'th gear won't shift, same error codes.

As I could not find an answer anywhere, I write here the solution (at least in my case), in an attempt help the next measurable guy. After more than a month of countless false attempts, it turned out that the problem was in the timing belt. It "jumped" two teeth away from its right position, in one of the camshafts sprockets.

The problem was just a weakening of the "automatic stretcher" of the timing (aka spring). Re-aligning the timing belt to its right place will not solve the problem as in the next steep hill it will jump again. The timing belt mechanism, especially the stretcher, must be replaced with a new one.

Pay attention aveo owners: (In my experience) the timing belt mechanism in chevy aveo (2004) is amazingly, unbelievably, poorly designed and poorly constructed. It’s a huge weak spot that could ruin perfectly good-condition engine. Frequent checks are recommended.

Sticking lifters will cause all 3 of these codes simultaneously and unfortunately intermittently as well. Changed a head from a broken timing belt and had these 3 codes stick around for a week.

Just put a reman engine in a 2004 aveo with 61000 miles (sat up over 15 years). Engine runs smooth but Now gets these 3 codes. Have not completed diagnosis on a good computer, but the dry rotted tires are bouncing bad (listed as possible p0300 cause in thread above). Will update when diagnosis is complete.