'04 WJ fuel filter/regulator trouble

mcvayl · 11-03-2009, 07:25 AM

I have an '04 WJ and I resently changed the fuel filter/regulater at 53k miles. I followed the steps from WJJEEPS.com on how to release the pressure on the fuel system and how to change the filter. Now the 4.0 will not start on the first try, usually after I kick it over and then try the second or third time. When I drive it, it feels like I have no fuel pressure, especially after coming to a stoplight and then moving again. The RPM's get down to around 500 and it almost feels like the engine wants to die until I hit the gas. I am hoping it is not the fuel pump because I know what that entails. But everything was fine until I changed the filter and now these problems. Any help would be greatly appreciated, as this is my daily driver and I need it for college. Thanks

rm2001wj · 11-03-2009, 10:29 AM

I don't have first hand experience with this, and I'm not going to crawl under mine to check this out, but is it possible that a couple of lines were interchanged when installing the new one. Maybe the type of quick disconnects being used would make this impossible; I just don't know.

It's is hard to see how swapping a working regulator/filter for a new one would cause any kind of problem unless the new one was faulty to begin with. Any air that got into the fuel lines should have cleared out quickly.

**walter_da_jpr** · 11-03-2009, 11:28 AM

Any air should be out by now. Make sure you do not have any leaks, maybe your losing fuel pressure/flow.

georged · 11-03-2009, 11:51 AM

Are you talking about the filter on the fuel pump inside the gas tank? If not where is the filter/regulator you are talking about?

**walter_da_jpr** · 11-03-2009, 11:53 AM

It is above the rear axle mounted to the body.

mcvayl · 11-03-2009, 12:05 PM

The only thing I noticed with the new filter was that on the side that has 2 connections, one from the fuel pump and one for the fuel return, that they were backwards, meaning that on the one I took off the return was on the back and the pressurized (fuel line) was on the front side of the filter. I know I didn't mix these up in any way since those 2 connections have different connectors and the side going to the fuel rail only has one connection. And when bolting it back on, it only goes on one way due to the offset of the mounting holes. I read that air may have been an issue but it has been about a week since I changed it. It hasnt gotten any worse but its not getting any better either. Thanks again!

rm2001wj · 11-03-2009, 12:39 PM

You didn't keep the old filter/regulator by any chance did you? If you did, you should put it back on and see what happens.

mcvayl · 11-03-2009, 12:45 PM

I wish I had now. It just goes to show never throw anything away. I think I might just break down and buy another one and see if that changes things. It was the only one at my local Autozone, so if that tells you anything. Who knows what abuse it has taken and it did have a 2008 production date on the box. So maybe just a bad filter. I will pick one up at NAPA tomorrow and slap it on and see if that works. But keep up the posts if you think of anything else. I need all the help I can get. Thanks!

mcvayl · 11-05-2009, 06:41 AM

I also noticed after reading a few other threads that my tranny shifts high at acceleration. I just changed the fluid and filter to AMSOIL at the same time as the fuel filter. I dont know what is going on with my poor jeep. Makes me feel like everything I have done has just made it worse and worse. I need help ASAP. Thanks again!

rm2001wj · 11-05-2009, 07:17 AM

Chrysler recommends using only AFT+4 in WJ transmissions. It's not a good idea to use a universal transmission fluid like Amsoil. Most auto manufacturers recommend using a specific fluid for their transmissions, and the fluid is different for different manufacturers. You ignore their recommendations at your own risk.

**Ridin' Around** · 11-05-2009, 09:46 AM

The Amsoil fluid is just fine for the replacement of ATF+4, if not better.

mcvayl · 11-05-2009, 01:24 PM

Thats what I thought too... Plus I'm sure if AMSOIL was not recommended for your Jeep the AMSOIL website would not tell you to use it or give you the fluid requirements for the tranny you have... and it says on the bottle if I'm not mistaken ATF+4 equivalent. But just changing the fluid over should cause that problem.. I wouldn't think anyways.

rm2001wj · 11-05-2009, 02:48 PM

It's pretty much a waste of time to argue with Amsoil converts, so here is a another suggestion. Maybe when you were changing fluid and filter the throttle valve adjustment was changed a little. That could cause the problem I think you are having. Use this link to see how to check it and readjust it if necessary..

I have a 2002 jeep grand cherokee with the 42re ... - JustAnswer

mcvayl · 11-05-2009, 07:04 PM

Thanks for the link.. I just found out that I have a P0340 code that might be why my I have been having my fuel issues. I am going to replace it tomorrow and see if that will solve what has been going on. I am a recent Amsoil convert so I might be in the wrong as well with my tranny problem. But I appreciate the advice and will repost with the results. thank you again for all your help!

mcvayl · 01-02-2010, 06:52 PM

I found the problem. It was a bad fuel filter that caused all the ruckus. i cant believe it. I went to NAPA and bought another filter, put it in, and it started right up on the first crank. No more transmissions issues or anything. I think that was caused by lack of fuel, hence lack of power, when I accelerated onto the turnpike. And now my MPG has went from 14 to 20. (the best part 14 MPG was at 70MPH and 20 MPG was at 80 MPH) I am getting great gas mileage!!!!! So if anyone is having any issues like I had check your filter. And if you change it, check that its sealed properly. Thanks again for everyone's advice! If I have anymore issues I will be sure to ask! Thanks again everyone!