NA Fuel Problems

[P_Bazz]

To start off with source of the problem, about a month ago my NA just died on the highway. A lack of fuel to the engine, I was towed to the local Mister T and they told me the Pump control Ecu was the problem. So I went ahead and did the 12V mod on it thus bypassing said ECU. My problems were gone for about a week. Then one day the GE started juddering heavily above idle, almost like a misfire but with absolutely no power left in the engine. I had already driven quite a bit and the engine was warm. When I came home (it started shaking at the beginning of my street) I turned the car off but noticed that the fuel pump was still running. I could hear the pump in the back buzzing and petrol flowing in the engine bay. So I disconnect the battery and replaced the EFI relay. Went for a test drive the following morning and everything was ok again.

 

I decided to drop off some rims that afternoon and the car was warm when I arrived at the garage. But then as I was about to leave 5 minutes later it started and idled normally but it was doing the harlem shake again above idle. I restarted the car and the problems were gone. Then I had to pick up some groceries for my grandparents so I headed to the shop and later to their house and after both stops I had to restart the car about 5 times for it to run normally so I could get home.

 

Today I replaced the fuel pump with another stock pump. Again I warmed up the car with some driving around the block and returned home with no problems. I started the car again a few minutes later and still no problems. I went inside for diner and returned to the car about 90 minutes later. I turn on the ignition and I'm hearing the petrol flowing but when I start the car it judders even at idle this time, I turned it off again and decided to call it a day.

 

I was hoping maybe one of you guys had the same problem or has an idea what the heck is going on in my car? Because I do not know where to look anymore as I was convinced that it was the pump.

 

The car has fairly new plugs and leads, the rotor and distributor looked OK when I replaced the leads but I will check them again tomorrow. Another thing I found strange was the sound of petrol flowing through the engine I had never heard that before but I think that is because of the 12V mod for the pump?

[Guest Roger NE]

Firstly, what exactly was the 12V Pump ECU by-pass Mod you did?

 

Need to know that to diagnose the other symptoms you describe (for example - you may now have the fuel pump being powered all the time the ignition is on, whereas the Pump ECU only powers it when the engine is running or cranking)

Edited November 11, 2013 by Roger NE (see edit history)