When accelerating the car jerks

Hi ASIAC,

This sounds like a misfire but that needs to be confirmed. Do you have a check engine light on or any codes in the system?

If not, it could be a vacuum leak. Here is a guide on vacuum leaks:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Let me know if you have any codes and we can go from there. There is a chance that this is a transmission issue but I would suspect one of the above reasons first.

Okay. You will want to diagnose the large evap leak but I don't think that is causing the jerking issue. I think your EGR valve code is the issue.

Attached is the test that you need to follow. Pay attention to where it says that your 0404 code is saying the the actual vs command position of the EGR are not the same. This means that your EGR is more than likely stuck. If this is the case then you will have performance issues when accelerating because the EGR is open during times it should be closed.

I would not just replace the EGR without running through the test because there is a small chance it is a module or wiring issue. However, I would take it off first thing and look for deposits as it states under diagnostics aids.

If you find out that it is the EGR then yes, that is pretty easy but again, you need to run through the test so you don't unnecessarily replace the part. Also, I do NOT think it is the transmission. The EGR valve is part of the engine and controls the amount of exhaust gases that get engine reuses to reduce the harmful emissions.