Check Engine Light
 

Hello,

I had to replace a faulty oil pressure sensor (it was leaking and casuing an oil light at low engine speed). The replacement was strightforward, but now my check engine light is on. I'm puzzled because my Hanes book indicates that an abnormal oil sensor voltage (hi or low pressure) will not trigger a check engine light. There really aren't any other sensors near the oil sensor so I'm pretty sure that I didn't affect anything else.

Any thoughts?

Regards,
Bill

RE: Check Engine Light
 

get it scanned and find out what it is

RE: Check Engine Light
 

More details. I checked the codes by turning the key on/off 3 times. Two codes came up: P0456 small leak in the evap system and 1684 battery disconnected in the last 50 starts. I didn't touch the evap system and have never disconnected the battery. Also, according to my Haynes book neither one should illuminate the CEL.

Any further thoughts?

RE: Check Engine Light
 

thats wrong the evap is a fed mandated system and that will turn on your light more then anything else. U have a leak in a line,seal,part. With out a scanner that can force the test or a smoke machine u wont find it easy unless its a visual crack in a line.

RE: Check Engine Light
 

Well, I cleared the light the old fashioned way; I disconnected the battery cable for 15 minutes. It's been off ever since(about 1 week). I think the computer just needed a reboot.Previously, I couldn't even clear the fault using Autotap.

While I was searching the evap system (it appears several parts are on top of the gas tank, impossible to get to), I noticed that my gas fill tube was extremely rusted and that the ground strap had rusted off. I was going to tryto paint this to save it (if possible). Anyone have a problem with the gas fill line rusting through? I can't believe that Chrysler would cheap out on this system and use something like stainless steel. If it rust through and gas leaks, then it become a severesafety concern.

Bill

RE: Check Engine Light
 

Correction: ...and NOT use stainless steel...

RE: Check Engine Light
 

u may have turned on the light for now untill your computer relearns the adaptive numerator and then in a list will retest what caused the leak the first time and fail again all u did was make it harder for some one to fins the prob untill it comes back.

RE: Check Engine Light
 

Could've been something as simple as a lose gas cap. But chrysler tech is right. If there is a leak, once everything is relearned, it will trigger the check engine light again.

RE: Check Engine Light
 

Guess what? It came back. Same code (P0456). I replaced a couple of bad rubber hose sections, but I can't clear the light.

Is there any potetntial problem if I PRESSURE test (approx. 1psi) the system at the test port? I have a small pressure pump but not a vacuum pump.

Also, is it possible to inspect the partson top of the gas tank without actually dropping the gas tank? That may prove to be too dangerous for me...

Bill

RE: Check Engine Light
 

the 456 is a small evap leak the size is .020 of an inch leak.ne idea how big that is?? about the size of this . If u want to find the leak it can also be a part not sealing all the way ,or a line leak. Look all over where the tubes go and look for cracked lines in teh system. U wont be able to see or hear a leak of that size with your pump. If u had a vac pump u could make a 29 inch vac and break the system up in parts and see where the leak is comming form that way . Or take it to a place that has a smoke machine and can correctly figure out the leak.