Putting stock fuel pump back in car- questions

[leakyfaucet]

Hello, I'm on a serious budget with my 91 Tsi. Currently, it as a mystery fuel pump in it. I'm assuming its a walbro 190 or 255 because it whines so loudly. It has not been rewired, however. The car had the stock fuel pump sitting in the hatch when I got it.

My car has been getting less than great gas mileage- usually about 20mpg and I drive conservatively. Boost also has been coming on rather slow. I'm considering the possibility of the aftermarket fuel pump overrunning the FPR and causing the car to run rich, so I want to put the stocker back in.

I've never swapped fuel pumps before, but from what I understand, the biggest problem is getting the old fittings apart, which shouldn't be a problem since it has been done recently.


Are there any new parts I will need to put my stocker back in? Or will everything I need already be on the aftermarket pump that's inside of it?

 

[megadeth0]

Everything is already in there. Just set aside an hour and go to it.

 

[97EclipseGS-T]

I would definatley go for an aftermarket one. If that IS a walbro 190, keep it on there and just rewire it. I want to say that it whines like crazy because it depends on the voltage on the wire and wants to take advantage of it. I mean, stock will still be fine with a rewire, but for future mods, the 190 will be probably the best bet.

^^^^ yup, everything is there. I did mine and it took only about 1-2 hours. The pump comes with filter o-ring, and a small circle clip... don't loose that thing. I lost it and had to get a new kit for my walbro 255, pain in the ass.


-PAUL

 

[alex]

Rewire kits - $15+Shipping (Ebay)

Yes, if it is a Walbro 190, I would keep it in there and just run a rewire kit. For me, the first time I did a rewire kit, it was kind of tricky. After that, its pretty easy for the most part.

What you could do to determine if you are running rich or not is take out of the spark plugs. If they are white, you are running lean. Black, you are running rich.


If it is a Walbro 255, I would probley take it out and put the stock one back in. You'll need an aftermarket FPR, etc.

-Alex

 

[leakyfaucet]

Thanks for the advice guys. I probably will just rewire the stocker. The most boost I would probably ever run is 17-18psi on the 14b. A stock fuel pump rewired should be able to handle that with no problems, right?

If I ever decide to make more power, I can always put the mystery pump back in, once I figure out what it is.

Edit- I was poking around my Haynes manual and it said I needed to put in a new gasket for the opening of the tank. Do I really need a new one or can I just use RTV?

Thanks!

 

[femmeDSM]

Thanks for the advice guys. I probably will just rewire the stocker. The most boost I would probably ever run is 17-18psi on the 14b. A stock fuel pump rewired should be able to handle that with no problems, right?

NO!
If you're planning on that much boost, keep the Walbro. A stock (rewired) fuel pump won't be able to handle more than about 14psi. Running this much boost will fuel-starve your engine, and can lead to what they call "catastrophic engine failure" (a.k.a. "Engine No Work-y" syndrome)

If I ever decide to make more power, I can always put the mystery pump back in, once I figure out what it is.

There should be a model number stamped on the side, assuming it's Walbro.

Edit- I was poking around my Haynes manual and it said I needed to put in a new gasket for the opening of the tank. Do I really need a new one or can I just use RTV?

Honestly depends on the condition of the gasket. I know you should "technically" always replace every gasket if you take something apart, but amazingly, mine was in like-new condition, so I just RTV'd it. Use your best judgement.



And one more time, for emphasis: DO NOT RUN MORE THAN ~14psi ON THE STOCK PUMP! Please

 

[leakyfaucet]

^^^
Okay, I won't =)

Thanks for the advice!

Edit: Wait, won't it reach fuel cut before it hurts the engine? I don't plan on doing any tuning mods so the factory fuel cut should save my ass if I decide to push the motor too far, right?

 

[femmeDSM]

^^^
Okay, I won't =)

Thanks for the advice!

Edit: Wait, won't it reach fuel cut before it hurts the engine? I don't plan on doing any tuning mods so the factory fuel cut should save my ass if I decide to push the motor too far, right?

You might reach fuel cut, and you might not. Fuel cut is the ECU's last line of defense before the aforementioned "Engine No Work-y Syndrome". Turning up the boost and using Fuel Cut as a failsafe is no good, for many (obvious?) reasons.

You're doing things backwards, it seems. The best way to tune your way out of reaching Fuel Cut is to increase fuel (by way of larger injectors, SAFC, and fuel pump), not DEcreasing fuel and INcreasing airflow at the same time. That's just..............Not right............

If your goal is running 18psi safely, you'll need at a MINIMUM a rewired Walbro 190, SAFC and larger injectors. Anything less than that would be risky. The setup you're describing (stock fuel, stock turbo) would be devastating to your engine. To say the least.

 

[leakyfaucet]

I was just wondering, wasn't seriously going to rely on it. I'll just run stock boost with the stocker, and maybe rewire it while I'm at it, just for an extra margin of safety.

I'll decide what to do with the mystery pump once I figure out what it is. So you say if the pump is a walbo it will say right on the side if it is a 190 or 255?

Thanks again