hard start video

[bastianshaw]

thoughts?
im thinking fuel pump?

[E30_fiend]

How does it run once its actually started?

[bastianshaw]

How does it run once its actually started?

ZERO issues

[E30_fiend]

if its a pre 09/87 325i, then it has the dual pump system. Usually what happens with those is the in tank lift pump fails leaving all of the work up to the external high pressure pump. It will work for a while but then eventually it will cause issues.

I think what you're experiencing is the high pressure pump struggling to get enough fuel to the motor. Then, after a few tries, it has enough pressure to get the motor fired.

My advice, get a new lift pump AND high pressure pump Although, you will probably be able to get away with JUST replacing the in tank pump.


Taylor

[bastianshaw]

if its a pre 09/87 325i, then it has the dual pump system. Usually what happens with those is the in tank lift pump fails leaving all of the work up to the external high pressure pump. It will work for a while but then eventually it will cause issues.

I think what you're experiencing is the high pressure pump struggling to get enough fuel to the motor. Then, after a few tries, it has enough pressure to get the motor fired.

My advice, get a new lift pump AND high pressure pump Although, you will probably be able to get away with JUST replacing the in tank pump.


Taylor

I have a in tank pump from a later model I will that work?

[E30_fiend]

In order to make it work, you will have to remove all of the outer pump components and install new soft fuel lines.

I assume you have the entire late fuel pump assembly to drop in? Not just the pump? Reason I ask is because if you have JUST the pump then you'll have to do some trimming to make it work but it WILL work.


Taylor

[bastianshaw]

I have the pump and sender assembly.
when you say new lines are you talking the ones that go from the pump on top of the tank and under the seat? cuz f that noise

[bastianshaw]

any other ideas?

[Albuquerque30]

He meant to remove the external pump and put new soft lines down there in it's place. It's all pretty simple, I did it in my old eta a few years back.

[bastianshaw]

He meant to remove the external pump and put new soft lines down there in it's place. It's all pretty simple, I did it in my old eta a few years back.

what would be the problem w not removing the external pump?
excessive fuel pressure?

[jlevie]

Before you start replacing parts diagnose the problem. The first checks would be to:

1) Have a smoke test done and fix the leaks it reveals.
2) Tee in a pressure gauge and see what the rail fuel pressure is/does when starting.
3) Check the ECT sensor, at the sensor and at the DME connector.

The in-tank pump from a later model can't be used as is because the assembly doesn't have the fuel return fitting. The in-tank pump could be bad, but I doubt it is the cause of this. When the tank is above 3/4 full (as it was in the video) a failed transfer pump usually doesn't cause any problems. The effect of a failed transfer pump becomes progressively more noticeable below 3/4 of a tank. But in any case you can test the pump to see if is working.

[bastianshaw]

Before you start replacing parts diagnose the problem. The first checks would be to:

1) Have a smoke test done and fix the leaks it reveals.
2) Tee in a pressure gauge and see what the rail fuel pressure is/does when starting.
3) Check the ECT sensor, at the sensor and at the DME connector.

The in-tank pump from a later model can't be used as is because the assembly doesn't have the fuel return fitting. The in-tank pump could be bad, but I doubt it is the cause of this. When the tank is above 3/4 full (as it was in the video) a failed transfer pump usually doesn't cause any problems. The effect of a failed transfer pump becomes progressively more noticeable below 3/4 of a tank. But in any case you can test the pump to see if is working.

so whats your guess?

[jlevie]

so whats your guess?

I avoid guessing as much as possible. Instead I do the diagnostics so I fix the right things the first time. Follow the list above.

[E30_fiend]

Jim is usually right. Only rwason I suggested what I did, is because I had this exact issue a few weeks ago.


Taylor

[bastianshaw]

Jim is usually right. Only rwason I suggested what I did, is because I had this exact issue a few weeks ago.


Taylor

word thats one of the reason I post, sometimes we have had the same exact problem and its reasonable to take a stab in that direction