Running too Lean

[left3field]

Hi All,

I Just posted a problem with my cruise control, and have one more issue to request help on. I have an 2003, and have had the check engine light come on. I brought it in to have the code checked, and it showed that its a "running too lean" code. The symptoms are after driving it for say 30 plus miles and stop, attempting to restart, I have to pump the gas a little as if the "choke" is not working. I have been told it is probably a vacumm hose or an O2 sensor issue. Has anyone run into this before, and what did you check to fix the issue?

Thanks,

Terry

[JohnO]

I presume you have a P0171. This is usually a dirty MAF or a vacuum leak. If it occurs during cold weather it is usually the intake manifold gasket. A redesigned one is available because of the prevalence of the problem.

Have you cleaned your MAF recently? They should be cleaned when the air filter is replaced.

For the intake manifold gasket, see this thread:

viewtopic.php?f=17&t=40338&p=477082#p477082" onclick="window.open(this.href);return false;

[biodieselrabbit]

There are some pictures of replacing the intake manifold gasket on the following thread too.
viewtopic.php?f=20&t=33056" onclick="window.open(this.href);return false;

[Salsa Guy]

The MAF are tender devices and can be easily damaged if improperly handled or cleaned and recommend not cleaning. A lean code is normally caused by un-metered air getting into the system normally cause by a Vac leak. The intake manifold gasket is a likely culprit, followed by cracked or worn Vac hoses, then possibly a bad upstream O2 sensor.

The P0171 means the ECU needs to adjusts the fuel trim more than 20%.