CEL on the way home, questions

[fireguy12117]

98 with the 2.5...

apparently ive got p0133, p0402 and p0401 (pd) for codes.

did a quick search for the codes and it seems the 133 is an o2 sensor, the 1401 is insuffecient egr flow, 1402 is egr flow which seems strange to have both get thrown, but anyhow. are there any "usual" suspects with this motor? ive got more wrench time on a 4.0, but im not afraid to learn this 2.5. im going to start ASAP with the typical vacuum line/wire harness inspection and go from there, but id like to know if there are known trouble spots to keep in mind with this motor.

the 1402 looked like 1402pd on the scanner. no idea what pd is. also, changed the MAF last summer, thats about the only usual repair/change done to the truck.

 

[Hardwareman]

Usually when the EGR goes bad it will automatically throw codes for 02sensors. If you think about it, it's downstream therefore the 02's can't read conditions properly.




Allen

 

[fireguy12117]

oh yeah, i know the O2 and EGR componants are directly related, it all ties back to engine control through the pcm.....what i suppose i was really wondering was, is there a known few items that always come up as possible suspects with these engines? the 4.0 always has a leaky upper intake, or IAC's wreaking havock. in just surfing those forums, ive picked up some things. ive not spent much time on the 2.5, but basically once you know what different systems are and what they are for, it doesnt matter if its a 1.8L, 7L, GM, ford for chrysler IMOP....ill work my way through it, but this place always helps buku

anyhow, i put a vacuum pump on the egr and heard something lightly click/popping as i applied vacuum. this a good sign?

(i had promised to take the old lady out tonight, so im shooting in the dark with only having pulled codes and had 10 minutes before we went out for the night...)

 

[shadetree]

DPFE sensor. shady

 

[Wicked_Sludge]

you need to watch the EGR valve while you apply vacuum to it. you can see the valve move if you watch it. alternatively, you can apply vacuum to it while the truck is running. no vacuum should idle fine. full vacuum should idle like crapola.

DPFE sensor is a very good possibility..but dont rule out a bad EGR valve or plugged EGR ports...these 3 are the most common failure points.

 

[amar67]

I just got this CEL today P0133. This is the first time I have seen it and it is the only code. Has this been confirmed as the bank 1 pre cat 02 sensor? I have seen where the CEL goes away on some of the posts... should I just wait a few days and see if it goes away or should I blindly change the 02 sensor?

 

[97ranger xlt]

I just got this CEL today P0133. This is the first time I have seen it and it is the only code. Has this been confirmed as the bank 1 pre cat 02 sensor? I have seen where the CEL goes away on some of the posts... should I just wait a few days and see if it goes away or should I blindly change the 02 sensor?

holy thread hijack batman

i like to clear the codes and then drive it and see if the code re-appears or if the computer sets a different code....