Code P0401
#1
03-11-2005 | 01:14 AM
Thread Starter
Joined: Mar 2005
Posts: 1
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Code P0401
Need help diagnosing P0401 on wife's 99 Sebrng JXi...2.5L
Code is for an EGR flow problem but where should I start testing? I found a vac leak(not egr related), reset CEL and light stayed off for a couple days but is back on now. I have not had a chance to get out the Mighty Vac to test the egr valve movement but will do so this weekend. Any way to test the flow sensor thingymajig on the front of the engine that the egr vac liine goes to? I do not have a shop manual. I have searched this sight and many other but have found a single case of an egr problem on the 2.5L.
All suggestions welcome.
Code is for an EGR flow problem but where should I start testing? I found a vac leak(not egr related), reset CEL and light stayed off for a couple days but is back on now. I have not had a chance to get out the Mighty Vac to test the egr valve movement but will do so this weekend. Any way to test the flow sensor thingymajig on the front of the engine that the egr vac liine goes to? I do not have a shop manual. I have searched this sight and many other but have found a single case of an egr problem on the 2.5L.
All suggestions welcome.
#2
03-19-2005 | 09:54 PM
Joined: Oct 2004
Posts: 32
Likes: 0
RE: Code P0401
Is there any chance your EGR valve is clogged or carboned up? Also, check the oxygen sensor. My 1989 Spirit 2.5L SOHC threw a CEL once because evidently it occasionally tested the EGR by opening it slightly and reading the impact on the oxygen sensor (because of a shift in air/fuel mixture). It failed the self-test and lit up a code which indicated an EGR blockage, but a new oxygen sensor solved the problem, instead.