Whats Wrong with my engine, trouble code p4133

[HERSHEY10]

I have a 1996 ford ranger v6 4l. A few months back my check engine light came on, so I read the code and it came back as (p1443 evap emission contol valve). I also have a loud vacumm noise coming from the engine bay when im idleing, as well as poor gas mileage (~10mpg city). Anyone know what the problem is (the gas cap is fine). Ive done research on the code but all the info I find leads to a multitude of things, not just one issue. Also this may or may not be related, but when Idling after driving (ie. at a stoplight) the engine revs to 2500-3000 rpm and then back down to the normal 1500, thn back up again.

Thanks for anyhelp you can bestow upon me...

Hershey

 

[tad]

Check idle air controller, clean MAF, see if that helps. Sounds like you have a vacuum/exhaust leak too, check your hoses/manifold.

 

[armadillon]

^^This

 

[adsm08]

Check idle air controller, clean MAF, see if that helps. Sounds like you have a vacuum/exhaust leak too, check your hoses/manifold.

Not this. Not yet anyway.


This is a guess, but an educated one based on the information, codes, and symptoms you have posted.

Replace your evap canister PURGE valve. There are two evap valves, the purge valve is on the engine side and opens to allow vapors that were caught in the canister's carbon matrix to be drawn into the engine and burned.

The vent valve (you aren't interested in the vent valve right now) opens at the other end and allows fresh air in to displace the fuel vapors.



When the purge valve gets stuck open and the vent valve is closed it can allow vapor to be pulled from the top of the tank, it can even pull a vacuum on the tank and make the fuel vaporize faster, and draws all that into the intake manifold causing all sorts of fun issues like erratic idle and bad fuel economy just to name a few. It's almost like putting a carb in front of your fuel injection system.

 

[HERSHEY10]

@adsm08

Ah then that would explain all the problems I have, but does that include the vacuum noise (which only occasionally) sounds when idling, but goes away as I drive?

 

[adsm08]

Yeah, it can explain that as well. It basically opened a dime-sized hole in the side of your manifold.

The manifold is under vacuum because the pistons create a low pressure area with their movement. The throttle plate closes off the intake and creates a pressure drop. That creates vacuum. When you get into the throttle it lets the manifold start to equalize to atmospheric, but more importantly to your noise it opens a much bigger hole in the manifold, meaning any noise generated by air movement through the smaller hole will be greatly reduced.

 

[HERSHEY10]

Ahhh well ok then, Thank you so much! Appreciate it

 

[jasonbeck0818]

Not this. Not yet anyway.


This is a guess, but an educated one based on the information, codes, and symptoms you have posted.

Replace your evap canister PURGE valve. There are two evap valves, the purge valve is on the engine side and opens to allow vapors that were caught in the canister's carbon matrix to be drawn into the engine and burned.

The vent valve (you aren't interested in the vent valve right now) opens at the other end and allows fresh air in to displace the fuel vapors.



When the purge valve gets stuck open and the vent valve is closed it can allow vapor to be pulled from the top of the tank, it can even pull a vacuum on the tank and make the fuel vaporize faster, and draws all that into the intake manifold causing all sorts of fun issues like erratic idle and bad fuel economy just to name a few. It's almost like putting a carb in front of your fuel injection system.

Hey I am having to replace my vent valve on my 04 4.0 and was wondering if you knew where it was located. I have found that canister at the back above the spare tire but I cant seem to find the vent valve. Is it more near the gas intake filler neck?
Thanks for your help