QuestionWith regard to the code, it was P0401. I was told that it is the EGR Valve, being faulty. I want to know if a vaulty EGR valve causes a Low Engine Oil light on. Because, the low engine oil light is on at times when I'm at a red light or at stop.
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I used to have a low oil light come when I sit at a light. I change to slightly heavier oil (5w40) Syntec and that seem to fixed it, but it still comes on, but not on a regular basis or as frequent. Now, the Check Engine light came on yesterday while in motion. What do this typically mean? Because, typically when a Check Engine light comes on, you supposed to take it to the repair shop immediately, which I am planning on doing.
Thank you,
Carter
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Hi Carter,
The check oil light situation sounds normal so I would not worry about that. The check engine light does not mean you have to go immediately to the repair shop, but rather to be aware that some aspect of engine operation is causing an increase in air pollutant release. It is desireable to find out why and correct it, but it is usually not an emergency.
The best thing to do is to seek the fault code that is stored in the engine controller memory and which will tell you why the light is "on". You may be able to get that youreself using the ignition key:"On-off-on-off-on and leave it on" doing this in 5 seconds or less elapsed time. Then watch the odometer window of the cluster to see if the mileage is replaced by any code numbers that begin with a "P" and then 4 digits. If so, let me know and we can consider what might be wrong. I assume that you have the 6 cyl. 2.5L engine, otherwise let me know. If no codes appear, then go to a shop to have them attach a reader to a 16-pin plug under the dash and get the codes that way. It should cost about $40 to get that readout; some auto parts stores, e.g. Autozone, will do a free readout. The code will tell you in what way the engine is malfunctioning but won't give the specific possible repairs. If you would like, write me back and we can discuss what to do.
Roland
AnswerHi Carter,
Yes, if the egr valve is sticking ajar that would cause the mixture to be too lean and the idle speed to be irratic which would lower the oil pressure at idle below normal. So dealing with the egr may help cure the oil pressure light. Here is an answer I gave to an owner of a 2.5L who had an egr issue:
"The first thing I would do is check the mechanical function of the egr valve which is located along a pipe that runs from the left exhaust manifold (on the side of the engine facing the front of the car) to the intake manifold area (where the incoming air in the large rubber tube enters the throttle). That valve is metal and has a round fitting with a vacuum hose attached, mounted on the top of the valve, and the round part is attached to the main body of the valve by a sort of saddle. Inside the open saddle you will see a metal rod (with a slot) that connects the round top fitting to to the valve body. That rod is a stem on the valve and it is supposed to go in and out in response to the engine vacuum which varies with RPM and throttle opening (gas pedal position). Take a spray can of WD-40 or other penetrating lubricant and spray the stem where it enters the valve body and then use a regular screwdriver blade tip inserted in the slot to lever the valve in and out to try and free up its motion. Also check all the rubber vacuum hoses associated with the valve and a nearby vacuum solenoid valve. If the valve seems to open (against the action of a spring) and close firmly by the spring action when using the screwdriver blade to facilitate the motion, then you should be able to now start the engine. You can, once it is idling, check that the valve stem moves when you rev the engine from idle to 2500 rpm and back to idle. If it still won't start, then removing and cleaning the interior of the valve, or buying a new one if it seems too crudy and corroded inside, is the next step to getting the engine to start."
If the stem seems to move well then it is probably an issue with the solenoid on the top or the wiring. But I would check the motion of the valve stem first.
Thanks for getting back to me with the code.
Roland
