I have a fuel filter in my engine compartment, on the drivers side fender well were the fuel lines come off and head to the injectors. Is this something someone added on, or is there a stock fuel filter there as well as the one under the car in front of tank?

 

AFAIK, there is only one fuel filter in the back. That's wierd that there is one in front. I would assume that someone added it in there.

 

Here is a pic. Looks like a factory style filter not an aftermarket piece. What do you think. Is it stock? Should I replace or remove?

 

You know how the cliche goes...

In this case, I don't think it matters if you remove it or leave it there. Does it drive fine as it is right now? If it does, leave it alone.

If you want to experiment, remove it and make sure you have an adapter between the two hoses w/ good tight clamps because it's a high pressure fuel line. You don't want your engine bay to have a fuel shower.

Here is a check to see if it is not supposed to be there. If the two connecting hoses are stock and whomever put that filter on there cut the hose to put the filter in, then the writing on the hose (the letters in yellow) should match up. If that's the case, that filter should definetely not be there.

Better check the fuel filter near your gas tank, just in case.

 

I have been having some weird problems lately, so I am trying to take out all possibilities and one is fuel not flowing properly, I already changed my other filter then I ran across this. Looks like normal cheapo hose clamps on there now, I am pretty sure the factory would not use high pressure AN type fittings that you see on each side of that hose and then cut it in the middle and hose clamp a filter there. So I guess my choices are replace it with another filter or replace that whole section of line.

Heres a dumb question. Are both those hoses there feeding fuel one to each fuel rail, or is one a return line?

 

One fuel line is the return line. I believe the smaller hose/line that is coming off your fuel rail is the return line.

 

I am guessing you could go either way with it, I sorta like the idea of having 2 filters, but is it really worth it... Personally I would just replace it with another filter, see if it seem okay then.

Thinking back I remeber seeing that on your car when we met up in Vallejo. I thought to myself, that's pretty smart! I hated changing my filter, I was literally soaked in gas up to my sholders, even my t-shirt. Oh and when they say relieve the pressure, I learned they mean it!

Bottom line in my book says, If you replace the filter, and it doesn't leak or anything, then it's a good thing all the way around.

I believe the smaller line is the return line, going back to the tank, but I am not completely sure. BTW hows your fuel pressure look?

 

Just got my fuel pressure gauge haven't hooked it up yet. I will probably play around with it Saturday morning. I imagine I will just replace that filter with something a little shinier! I still have the stock filter in the rear which I have replaced twice without needing to in the last two years. Problem is now I want an AFPR but before I get that I need to get my Plenum and runners ported, sanded and ready for powder coating, so I can do the job all at once.

 

thats a regular replacement aftermarket filter.

someone spliced it in there....

having a 2nd filter probly wont hurt anything, but im pretty sure thats a CARB filter... and its not made for the 30+PSI of FI systems....

i would just replace the regular filter in the rear of the car, and repair the hose with a coupler

 

i know you can stick it on a fuel rail, but you could always get a coupler that has the threaded fitting for a fuel pressure gauge and put a gauge there.... :lala:

 

Things that make you go HHmmm! Thats not a bad idea MrDude, Wouldn't be as visible there, as on the fuel rail, and I would need to buy some fitings. Can anyone think of a reason it would be better there than on the fuel rail? Is it a pain to attach these to the fuel rail, or is the fitting on the rail pretty easy to get to? Is the fitting on the rail before or after the fuel pressure regulator? How would it be affected with an AFPR on the hose by the fender well? I guess I am not real clear on where the AFPR makes the adjustment to the fuel pressure, does it send a signal to the pump to pump more, or does it build pressure in the rail itself that would not be read from a gauge further up the line?

 

the only reason i could think of is if you've already tapped that fitting for another use... like a nitrous system or somthing...



but i was just throwing it out there since the line was cut anyway.

thats where TBI guys have to put their gauge since they dont have another fitting built in.

 

The gauge would be much more out of the way there, don't really know if that's a good thing or a bad thing to you.. I would assume it would also be there for good in the line.

I am not sure how easy the gauge is to attach to the rail, although I would think it would be easy, it's a schrader valve, you just screw the gauge on right? Seems easy to me. The valve is in a bit of an akward place, it's on the passanger side rail, about 2 inches from the rear of the rail.

I don't know what good a fuel pressure regulator by the fender would do, but thinking about it, it would only let you lower the fuel pressure, if you left the stock FPR in place, as the stock one would still do it's job. Not sure if that is how you were thinking of it, or if that's even how it works.

The stock FPR builds pressure in the whole system by sending less gas back to the tank, restricting the flow of fuel, therefore the pressure in the line would rise, inside the rail, then from rail to pump. The fuel pump just pumps.

 

I did what everyone else with a TPI set up did. Use the schraeder valve as a source for your fuel pressure gauge.

Do a search for fuel pressure gauge on the schraeder valve and you'll find mostly everyone used a 90 degree fitting with a steel braided hose to the pressure gauge and mounted the pressure gauge in a secure area.

You could use an electrical gauge to go inside cockpit, but it's more expensive.

Also, if you use the existing schraeder valve fitting, remove the valve inside. I think it's like a tire valve, I forgot the technical name.

 

Hooked up the fuel pressure gauge and I am only at 37 PSI. I looked closer at that filter and it definatly looks just like the basice carb style filter. Not good for fuel injection. I will be replacing that section with some new braided line and hope that brings my fuel pressure back to where it should be. Otherwise I am probably looking at fuel pump replacement.

 

I thought normal pressure was anywhere between 36 and 42. I could be wrong though.

 

For some reason I got it in my head it should be 42. But I have never had any reason until now to find out for sure. I started another post with this very question a few minutes ago.

 

First of all, I am shocked that the single worm clamps have held this long. Second, FI fuel hose is rated as FI for a REASON!

Replace it immediately...if it fails, the pressure will rip it apart immediately and the massive fuel spray could torch the car.

omcrider...you can find that previous owners hose up a LOT of wiring and plumbing



Good luck,

 

Instead of repairing the hose, you could just go to the junkyard and get that hose from any GM v6 car for like $1.

 

The stock filter fittings were prob rusted and a yahoo put that inline filter in there!! I would replace back to stock ASAPand our cars run between 38-42 PSI as there sweet spot!!