service engine soon light

[pria222]

I have a 2000 Xterra, and just recently my "service engine soon" light came on. I took my car in for service and the service techs found code po325: knock sensor circuit malfunction and code po1401: Manufacturer specific dtc. Not sure what any of this means, but I need a second opinion before I am charged outragous prices for something minor. Because I read up information about the "check engine light" coming on and found that many people reported that the problem for the light coming on could not be found or was due to really minor problems.

Any input you can give me about the codes that the service techs found would be really helpful.

Thanks!

[DAEDALUS]

I don't know how different your car is from mine. I have an OBD I '90 Q45. Your car's an OBD II. A very common thing is for one problem to cause 2 error codes, and very often one of the error codes is the knock sensor. For example, if I have a bad injector, it'll cause the car to run very rough. The bad injector will give one error code, and the rough-running engine will create an error code for the knock sensors. If I replace the injector, it fixes the rough idle and both error codes disappear. Again, not sure if this is entirely relevant, but I would investigate the po401 error first. They should give you info a little less cryptic IMO. That's like paying them to tell you that you've got an error light on. Duh!

[ricebike]

P1401 EGR Temperature Sensor

geez, I agree, they should have told you what that code meant if you paid $ for it... time to look for another dealership.

[pria222]

Thanks guys for the input.... I think I was given the least bit of info possible, because they probably wanted me to pay more to get repairs I didn't need done. They told me some main oil seal was leaking and it would cost $950 and it was leaking pretty rapidly and I should get it done soon........well guess what I got some second opinions and it turns out it wasn't leaking after all......strange huh!?!? could it be since I was female that these additional repairs needed to be done.

On another note... how often should someone get their power steering fluid flushed?

thanks!

[Q45tech]

Depending on how long you want the part to last, you compare used fluids to brand new: color and smell on a white paper towel.

ATF and PS fluids contain temperature sensitive RED DYES when these lighten [red washes out] they have been subjected to overheats.

If you want +200,000 miles you just change all the fluids every year [ANNUALLY] including the Brake, ATF, PS, traction, differential and the engine oil every 90 days.

Sure you can defer changes but without lab analysis you don't know for how long and what the effects are.

Remember the whole US economy is predicated on selling 16 million new cars per year. If you [and 10 million others] don't abuse your car and keep it just a year longer the economy could collapse.

Fluid color and smell will tell you everything!

[punkblackS14]

that knock sensor going off means you need to stop using the crappy gas and use 91-93 gas like the dealer reccomends.

[drjohn]

If the egr temp sensor is not seeing any temp change or to much change when it isn't needed then the ecm sets a code. If the egr is inop then it causes pinging in the eng. and you get the knock sensor code.The knock sensor code will be stored in ecm memory but by itself will not cause a check lamp to light.Possibly a clogged egr port or broken vac. hose.