I've had some weird issues lately with my car (91 CRX HF with b16 swap). First I was having a weird sputtering issue on slight inclines or on highway at constant throttle POS. Replaced plugs, wires, TPS, dist cap, rotor, etc..Found out it was because I wasn't running a 2nd o2 sensor. Well, I went ahead and chipped the ECU myself and made a custom tune based on the stock PR3 tune and disabled the 2nd o2 so now it runs great. I noticed my fuel pump was making some weird noises when the tank was low... grinding, loud humming. Because I'm about to go turbo, I decided to go ahead and throw a new pump in now. So I dropped the tank, replaced it with a walbro 255 (come to find out that's exactly what was already in there from the prev owner...he told me it was a oem/stock fuel pump.. ha..).

Well, all is well and running great except it doesn't seem to pump once the tank has gone thru about 6 gallons of gas (so 4 should still be in the tank, right..?). I was cruising along at 55mph and had a light change on me so I slammed on the brakes. I did this really on purpose to test my brakes out since I have slotted/drilled rotors I wanted to see how well she would stop. STOPPED fast. I take off from stoplight and I notice the motor seems starved of fuel (sputtering, etc..) and resumes ok for a a few minutes and then completely dies. I turned it over a few times and it sounded like the pump was not getting fuel. I coasted backwards (downhill) on a side road and braked a few times to try to get the fuel to the back where the pump is. I was finally able to get it to prime and make it to the gas station where I topped it off with 6 gallons (so 4 was still in tank).

Was the slamming on the brakes the main reason for this? I could see the issue if it was very low on gas but why would this happen even with 4 gallons still in there? Also, I feel good about the way I installed the pump. I used a new pickup screen and made sure everything was very secure with good wiring, etc.. This just surprises me.

 

Either the fuel sending unit is out of whack and your empty or the fuel pick up is not sitting at the bottom of the tank. 94

 

Didn't the HF model crx's have a 7 gallon gas tank? My old 1990 HF had a small tank. I would always run it close to E and every fill up was between 6.5 and 7.4 gallons.

 

Hmm, not sure about the capacity. I had a 90 si that was 10 gallon so I assumed it was same. I know the sending unit is normal but it's true that I've never been able to get more than 7.5 gallons in there.. hmm

 

More likely your fuel pickup is not setting at the bottom. I have a similar problem but it sputter around 8 gallon mark. HF model has slightly smaller tank (10.6 gallon compare to 11.9 Si/DX model).
My fuel sending unit is also not working (indicate that my tank is empty after running about 150 miles) so I just use my mileage gauge when I fill up.

 

That's what I was thinking. I put the new pump in just like the other one that came out so I don't know what the deal is. I may carry an extra gallon of gas with me and drive it until it runs out (or see if it happens again below a certain ammount). The sending unit seems to accurately reflect where the gas is since it corresponds to the mileage.

 

Indeed the problem is with the pickup/strainer that comes with the walbro. It's just not low enough... ARG! The fact that I still have around 4 gallons in the tank that I can't get to ain't gonna fly. I'm going to drop the tank again and use a different pickup/strainer.

I'm told the solution is to use a strainer like this: An Airtex FS121

 

Just confirming this is typical.

 

Yeah, but GRRRRR! My shoulders, arms, back, and FACE are just now recovering from the dreadful tank drop. Now... hmmm, which one of my friends has a car lift?