Check engine light came on with P0700 and P0738 codes

Hi:

I don't think the transmission is the issue. The P0738 indicates an issue between the transmission control module and the output speed sensor. Can you tell me what is happening? Was there only one time something happened?

As far as the P0700, it indicates that an emission related transmission DTC set in the Transmission Control Module (TCM).

Let let me know if the problem is continuing. Also, if you haven't, delete the codes and see if they come back.

Joe

It's not the first time or only time it does the jerking while driving. It does it all the time and it jerks 3 times when it does. I did delete the codes and those were the only two that came back on. When the car began to jerk that's when the check engine light came on. Everything else is good only when I drive the car all of a sudden jerks 3 times then goes back to normal. It will do it at random times too.

Hi:

Your description sounds like an issue with ignition. For example, a bad coil pack that allows a misfire and starts working again. A misfire does affect the emissions, but an additional code should have been present, too.

At this point, this is what I would do. If you have a live data scanner, you need to have a helper hold and watch the scanner to see if there is a temporary cylinder misfire. Also, if you have freeze frame capability on the scanner, see if anything shows up.

Do me a favor, if you have a live data scanner, let me know what the short term fuel trims are.

One last thing. You mentioned that these are the two codes which returned after you cleared them. What other codes were present originally?

Joe

I don't have a live data scanner but I do have the freeze frame capability on the scanner. I checked on the freeze frame for the short term fuel trims and it is showing 3.9%. The code that was present before was P0138 along with the P0700.

Hi:

The trims, although indicate the computer is adding fuel to compensate for a lean mixture, are within the acceptable parameters. A perfect case would be 0.

I have to say that I don't see how the transmission is causing what you described. If I had the vehicle, I would throw a live data scanner on it and drive it until the problem happened. I would most likely have a helper drive so I could watch the ignition and fuel system.

Since you still have a P0738, there could be an issue with a speed sensor, but I still don't see how that would cause the symptoms.

How often does the skip happen?

Joe

The car does this every time I drive at random times. And it always does it in set of 3 (it will jerk or skip 3 times) and then nothing. Oh, and if I let go of the gas pedal when it jerks after it stops and I try to press the pedal to accelerate it would not go (it would just be like if it is on neutral). I will look into getting the live data scanner. Thank you I appreciate all the help.

When you let of the throttle and then try to accelerate and it acts as if it's in neutral, what would happen if you manually shifted it to second gear? If you try it, make sure you are not going too fast.

Joe