check engine light question

[79elcamino]

i have a 2006 nissan sentra and my check engine light is on and the two codes that keeps coming up are something with vent and pressure senor low. the mechanic said it has to do with the evap system so i started to replace that senors and parts like for the evap system, i changed the pressure senor, egr valve, charcoal canister, gas cap, purge valve sensor, and the light keeps coming back on so i am going to bring it to nissan but i would like to know what it might be before i go so they dont give me some b.s. story and charge me a lot of money.any suggestions?

alittle off subject but i bought the car privately and after driving the car and letting it sit for about 30min i go to start the car and the car doesnt start the first time i turn the key, i have to turn the key let the motor crank then stop and turn the key again and the car starts. any suggestions?

Thank you

[Nappers]

Re: check engine light question

Has it had at least 5 cold starts since the replacing the componets? If not, usually needs that many to reset the light.

The best thing to do is get the codes, post them or google the codes and usually you can find an answer. My Yukon gave up a P1416 code and after a little research narrowed it down to Secondary AIR injection valve and I reset the light with my scanner and no problems since. I bought that cheapo scanner that's around 100 bucks.

If you don't have a scanner, then Pep Boys or Auto Zone maybe will scan your car and if you replaced the parts already, then they can reset the light for you and see if it pops back on......


Dang new cars anyways!!!!!

I like my '64 Chevy C-10, a screwdriver and a timing light is all you need.....

[79elcamino]

Re: check engine light question

Each part wasn't replaced at the same time everytime a part was replaced I reset the light and drove ad the light would come back on and I would replace another part.

[Eddie6th]

Re: check engine light question

I know this might sound stupid. Did you remove the fuse for the ECU for at least 20 seconds,with the engine off? If not,that can leave the trouble codes still in the memory and that could be why they still appear.

I reckon you have already done this as you have changed quite a few items.

[79elcamino]

Re: check engine light question

no actually i havent..., i did remove the negative connection to the battery only once though, and at the time only one or two parts were changed.

[Eddie6th]

Re: check engine light question

no actually i havent..., i did remove the negative connection to the battery only once though, and at the time only one or two parts were changed.

Removing the battery connection does the same thing. Try it again,but leave it for 20 seconds or so,reconnect,and start your engine and see if they clear.

[ClarkWGriswold]

Re: check engine light question

If it is an evap system code that set it off, check around the air filter housing and make sure all of the small hoses are connected. Some vehicle process the fuel fumes to a solenoid attached to or near the air filter housing and if the hose becomes disconnected, it throws the code. Good luck.

[Alex C.]

Re: check engine light question

Pressure sensor/ switch (out of range) is usually vacuum related. Look over any and all vacuum lines running from the intake manifold. An easy way to check the accessible hoses is to wiggle them while the engines running. Any hissing or drop in idle will point to an air leak.

[Alex C.]

Re: check engine light question

The starting issue could be a couple things. Have you tried priming the fuel pump a couple times before actually firing the engine? When was the last tune-up?

[79elcamino]

Re: check engine light question

The last tune was about 2 months ago I bought a k and n air filter Bosch plugs the mechanic said the car didn't have a fuel filter , which I found hard to beloved but I looked aroud the motor and I didn't see one and I'll take a look around the hoses thanks guys

[Alex C.]

Re: check engine light question

I'm referring to your fuel pump (probably in-tank). You might not have a fuel filter.

So have you tried priming the fuel pump a couple times before actually firing the engine?

[79elcamino]

Re: check engine light question

no but i shouldnt have to,the car should start no matter temperature it is, the car cold starts fine, i actually had this problem with my el camino and it wound up being the starter

[Alex C.]

Re: check engine light question

the car cold starts fine

Knowing that now, it probably isn't the pump. Just trying to rule components out one at a time. Could be the starter getting heat soaked. How old is it? Your power and grounds good?

[79elcamino]

Re: check engine light question

Just got back from the dealer it was the fuel pump which was the pressure problem then the other code was egr valve was loose so $700 later I pull away and the check engine light comes back on so I go back and now I need a new ecu cause it's not accepting the reset but it's covered under the warrenty. Thank you all for ur help

[scott0999]

Re: check engine light question

whenever you get a check engine code you should then look it up on alldata. it has all the steps to troubleshoot it instead of just guessing...