You are here:

Nissan Repair/2001 Nissan Altima


Car is hesitating when accelerating, almost seems to sputter, and engine appears to be running hot. (check engine light has been on since we bought the car w/00400 code garage said wasn't the problem). Oil was low. Seems to happen whenever it rains. Help???

Hi Barbara -

The code P0400 is EGR (Exhaust Gas Recirculation) valve malfunction. If I was the mechanic, I would not be so quick to discount this code, as a stuck or clogged EGR valve could cause performance problems in the advance stages of failure, which could be why your problem never surfaced til now.

If you have not done an OBD (checking for codes), recently, i would suggest you do it again, and let me know what the numbers are so i can assist with diagnosis. I think Autozone does it for free, if you have one in your area.

Other than that I would check or do the obvious for now, such as a tune up, including replacing plugs and wires. A lot of times these cause misfires, which will display a code. This is what we are looking for.

Hope this helps -

Nissan Repair

All Answers

Answers by Expert:

Ask Experts


Calvin Iwashita


All general car repairs for all models of vehicles, except technicals (overhauls) on A/C systems and transmissions.


16 years as a car mechanic from 1974 to 1990, and still repair cars on the side.


High School and college graduate

©2017 All rights reserved.