'04 Aveo Engine Issues

[NYChevoo]

wow! thats seems so complicated. i wonder how when cars are built that the ecu's are programmed for a car that just came from being nothing but parts on a warehouse shelf to the completed vehicle being loaded for delivery.

[petrified.rabbit]

stuff like that is really an "american" car thing.. most cars nowadays you clear the codes and everything goes back to normal...

[Konstantine]

I've had the memory "flashed" and after driving for 5 minutes the light comes on again with codes P1781, P0300 & P0700

[mikedudley17]

new ecu?

doesnt a flashing CEL mean that the ecu is crap?

[07_aveo]

doesnt a flashing CEL mean that the ecu is crap?

A flashing CEL indicates a misfire. The flashing is supposed to get you to stop driving I guess.

[mikedudley17]

doesnt a flashing CEL mean that the ecu is crap?

A flashing CEL indicates a misfire. The flashing is supposed to get you to stop driving I guess.

U sure about that? Gah I wish i could remember where i read that a flashing CEL means there is something wrong with the ECU...

U could be right and prolly are but I coulda swore I read that somewhere.

[subachad]

doesnt a flashing CEL mean that the ecu is crap?

A flashing CEL indicates a misfire. The flashing is supposed to get you to stop driving I guess.

U sure about that? Gah I wish i could remember where i read that a flashing CEL means there is something wrong with the ECU...

U could be right and prolly are but I coulda swore I read that somewhere.

Both right...

http://www.roberthancock.com/efi/

[xiaogary]

I had a flashing ecu once. The idling is very rough (running only on 3 cylinders) and engine died everytime I stop. Struggled to a nearby car parking area (abt 2 km away) to check my car. Supposed to stop immediately when CEL flashes, but no choice, have to get my car away from the heavy traffic so as not to cause any road hazard. So I didnt really stop when it flashes, just hope my engine dont blast along the way I force it to the car park.


Ended up is a fuel injector clip (electric) never locked in place properly (my mechanic never lock properly, so it jumped out after some vibration), so there is misfires. After put back in place, delete the code with a scangauge, its perfectly ok again. Check your spark plug, injector, and electric cables (sparks) first before investing in a new ecu.

[Konstantine]

Light is always flashing, and if I drive less than 80kph it's fine, but it won't shift up to 4th gear.
I now have 2 mechanics completely confounded by the thing.
And the kicker is, they both say compression is just fine, only the stealership claims my compression is off, I'm starting to distrust GM.
I hope I can get this thing fixed soon so I can trade the damn thing in!

[luklyz]

hi
Your mechanics are vary bad if they cant diagnose you car.
This is the list of your codes.
P700- Transmission fault code exists.
P1781- Power problem with trans.
p2610- Lack of power to engine ECU
P0300- random engine misfire.

Ignore the P300 code for now since the other codes all relate to a transmission electrical issue.
If the cel light was not on before the engine replacement then return to the repair shop and have them check the transmission wiring and engine ground wires.

Code p300 it is random misfire. You need to talk to your mechanic. If the new engine comes as a short block(naked engine just head, block and oil pen) or long block (with everything). (it is very important cuz your misfire can be cause by some thing else)

If you have the obd scanner you can try relearn procedure for crankshaft sensor
1. After night when engine is cold. Turn off all of the accessories. erase all codes
2. Start the engine and let it idle in Park or Neutral for two minutes.
3. Accelerate the vehicle to 55 mph at part throttle. Cruise at 55 mph for 8- 10 minutes until the engine reaches operating temperature.
4. Cruise at 55 mph for another 5-6 minutes.
5. Decelerate to 45 mph without using the brakes, and maintain 45 mph for 1 minute.
6. Perform 4 deceleration cycles, without using the brakes, of 25 seconds each where no specific speed is necessary. Returning to 45 mph for 15 seconds in between deceleration cycles.
7. Accelerate to 55 mph and cruise for 2 minutes.
8. Stop the vehicle and idle for 2 minutes with the brake applied and the transmission in Drive (automatic trans.) or Neutral (manual trans.) with the clutch depressed.

Good luck
Lucas