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Tomlouns

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Replace any fuel pickup filter/mat infront of pump inlet in case you got Alcohol “dandruff” from bad gas starving the pickup.
I checked it and it look very clean... only has 700 miles on that filter.
 
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I noticed that this issue doesn't happen when the motor is cold... Thoughts?
 

sigintel

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If the DW pump is designed for a return type fuel system and you run it non return, then you are stalling a pump not designed to be stalled. This may result in higher fuel temps and copper winding temps in the pump.
I would really go back to stock hat and fuel pump and wiring and retest lower rpm behavior and hot start.
 

turbofiveoh

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After watching the video my money is on the fuel pump.

When you depress the accelerator abruptly and the throttle opens quickly you'll get a large volume of air flowing past the throttle body and into the manifold. On a carburetor there is a mechanism called an accelerator pump that squirts fuel into the throat of the carb to address the sudden rush of air. On a fuel injected car there is a similar function in the software that delivers a bangshot of fuel when the throttle is opened quickly. If you have a fuel delivery problem you will get exactly the kind of symptom you are feeling when you quickly accelerate from a idle or low engine speeds. When you accelerate very gradually there isn't a huge rush of air that requires immediate fueling which is probably why the car feels fine when you are gentle on the accelerator.

Also, since the car is taking longer to start when it's hot that suggests that the fuel pump is failing. As a matter of eliminating the most likely problem you should put the stock fuel pump back in and bypass the boost-a-pump. I am almost certain this will solve your problem provided your stock fuel pump is still functioning normally.
 

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Tomlouns

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After watching the video my money is on the fuel pump.

When you depress the accelerator abruptly and the throttle opens quickly you'll get a large volume of air flowing past the throttle body and into the manifold. On a carburetor there is a mechanism called an accelerator pump that squirts fuel into the throat of the carb to address the sudden rush of air. On a fuel injected car there is a similar function in the software that delivers a bangshot of fuel when the throttle is opened quickly. If you have a fuel delivery problem you will get exactly the kind of symptom you are feeling when you quickly accelerate from a idle or low engine speeds. When you accelerate very gradually there isn't a huge rush of air that requires immediate fueling which is probably why the car feels fine when you are gentle on the accelerator.

Also, since the car is taking longer to start when it's hot that suggests that the fuel pump is failing. As a matter of eliminating the most likely problem you should put the stock fuel pump back in and bypass the boost-a-pump. I am almost certain this will solve your problem provided your stock fuel pump is still functioning normally.
Alright it is the last thing to try that seem like it may work... I went to do it today but I have to much fuel in the tank... it looked like if I opened it up it would spill all over the place... I think I need to get the tank down to 3/4 or less... before I can open it up ...
 
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Tomlouns

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Here is how I removed the gas ... does everyone see what’s wrong with the other photo ... the overflow isn’t hooked up and there isn’t even a clamp... I am not to happy with my installer right now....


So the big question do I connect it back up correctly and keep the dw400 or install the factory pump and use my voltage booster?
 
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Tomlouns

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FIXED! Now who gets the $50? A few of you pointed at the fuel pump... The car feels great! I would really like to thank everyone that took the time to help me out with this!
 

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FIXED! Now who gets the $50? A few of you pointed at the fuel pump... The car feels great! I would really like to thank everyone that took the time to help me out with this!
Glad you were able to solve the problem. It’s unfortunate that you spent good money for a subpar job. Definitely have a word with the installer.

The DW400 is a good pump and flows lots of fuel. The only complaint is that it doesn’t have a check valve. If you want to keep the DW400 my advice would be to do away with the boost-a-pump as the DW400 flows enough fuel to support gobs of horsepower. The next thing I would suggest is to install a one way valve in the feed line right after the pump. This way when you prime the system it will maintain pressure. If you choose not to install the one way valve the pump will still work just fine but you may need to crank the car for a little longer while the pump builds fuel pressure.

Have fun with the car.
 

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FIXED! Now who gets the $50? A few of you pointed at the fuel pump... The car feels great! I would really like to thank everyone that took the time to help me out with this!
Looks like it might be @sigintel who first said to pull the booster and pump. Go back to stock pump.

My thoughts on who got it first, and I have no replies in this thread prior to this one.

Glad you got it fixed.
 

sigintel

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C2F9A068-B9B3-4B87-AB2A-554C7F864022.jpeg
Pay it forward back to the community?
Someone will need your help one day.

Think Op actually had it in his data.

Because the fuel rail does not feed both sides evenly, when flow is corrupted with fuel vapor (stalled bypass type pump) or pressure drops, the differential short term fuel trim bank to bank comparison may show this non linear “flow load” vs “pressure” response.
 
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Tomlouns

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Pay it forward back to the community?
Someone will need your help one day.

Think Op actually had it in his data.

Because the fuel rail does not feed both sides evenly, when flow is corrupted with fuel vapor (stalled bypass type pump) or pressure drops, the differential short term fuel trim bank to bank comparison may show this non linear “flow load” vs “pressure” response.
If you don’t want it I will donate 100 to St. Jude’s children hospital... PM me if you change your mind... Thank you !
 

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If you don’t want it I will donate 100 to St. Jude’s children hospital... PM me if you change your mind... Thank you !
Wow!

That’s an awesome gesture! Much respect to you!

As a healthcare practitioner, I can promise you our third world “problems” are really insignificant to those with children needing assistance. Nothing is more difficult or more stressed.

Sorry sigintel, I vote St. Judes! This is certainly paying it forward as you suggested!

Well done!
 
 




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