320i fuel pump?

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Blanca
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Post Fri Dec 04, 2020 12:45 pm

I have a bit of a lazy fuel pump and it fails to prime on initial ignition on, no buzz, before I start so no start.
I looked at the tank unit under the seat and it seems to be a sender unit only with a pump under the car in front of the rear left wheel. is this normal as every reference I look at says the primary pump is in the tank?
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Lemon98
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Post Fri Dec 04, 2020 1:21 pm

Blanca wrote:
Fri Dec 04, 2020 12:45 pm
I have a bit of a lazy fuel pump and it fails to prime on initial ignition on, no buzz, before I start so no start.
I looked at the tank unit under the seat and it seems to be a sender unit only with a pump under the car in front of the rear left wheel. is this normal as every reference I look at says the primary pump is in the tank?
Should be the filter in front the rear left wheel, changed mine earlier this year.
1990 4-door 320i SE
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Blanca
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Post Sat Dec 05, 2020 12:47 pm

Lemon98 wrote:
Fri Dec 04, 2020 1:21 pm
Blanca wrote:
Fri Dec 04, 2020 12:45 pm
I have a bit of a lazy fuel pump and it fails to prime on initial ignition on, no buzz, before I start so no start.
I looked at the tank unit under the seat and it seems to be a sender unit only with a pump under the car in front of the rear left wheel. is this normal as every reference I look at says the primary pump is in the tank?
Should be the filter in front the rear left wheel, changed mine earlier this year.
Nope, that is in engine bay under servo. there is defo a pump under left rear, in front of wheel.
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Brianmoooore
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Post Sat Dec 05, 2020 4:51 pm

Early 320 has pump in front of wheel arch and filter at the rear of the engine bay. Later 320 has pump in the tank and filter in place of the pump, in front of the arch.
E30 pumps do not prime when you turn the ignition on. The pump starts when the crankshaft starts turning.
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Blanca
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Post Sun Dec 06, 2020 1:03 pm

Brianmoooore wrote:
Sat Dec 05, 2020 4:51 pm
Early 320 has pump in front of wheel arch and filter at the rear of the engine bay. Later 320 has pump in the tank and filter in place of the pump, in front of the arch.
E30 pumps do not prime when you turn the ignition on. The pump starts when the crankshaft starts turning.
So what's the 2 second 'buzz' coming from back there?
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Brianmoooore
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Post Sun Dec 06, 2020 1:41 pm

I've never heard a buzz from the rear. The noise a 6 pot makes when the ignition is switched on is from the ICV sorting itself out.