What will cause my car not to start. I'm getting a 1720 code

What is your question?

I bought the car and the owner said it used to die but start back up but it got worse and won't start at all. Gauge Says empty but it has gas in tank. Only runs on external fuel

What makes this problem better or worse?

Nothing. It doesn't start only cranks. When I run the fuel pump to a gas can I starts but runs sluggish

How long has your 2002 BMW 745Li had this problem?

A while

dukejs66 in Houston TX

Apr 28, 2018

Popular Answer

What are the best BMW repair shops?

RepairPal Certified shops can diagnose and repair your 2002 BMW 745Li. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.

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What is your question?

Popular Answer

What will cause my car not to start. I'm getting a 1720 code

What is your question?

I bought the car and the owner said it used to die but start back up but it got worse and won't start at all. Gauge Says empty but it has gas in tank. Only runs on external fuel

What makes this problem better or worse?

Nothing. It doesn't start only cranks. When I run the fuel pump to a gas can I starts but runs sluggish

How long has your 2002 BMW 745Li had this problem?

A while

dukejs66 in Houston TX

Apr 28, 2018

1 Reply

Popular Answer

DaveJMon Apr 28, 2018

Hello, if you have a loss of fuel pressure at the engine, it is likely you could have a fuel pump issue or something in the wiring to the pump. Keep in mind that the sending unit that makes the gauge work is associated with the fuel pump in the tank. Also keep in mind that this vehicle has 2 pumps - one in each side of the tank. They work to keep fuel balanced in the fuel tank, as well as provide fuel to the engine. One or both could have wiring or internal issues. The P1720 code indicates a problem in the networking of the vehicle, but could be due to low battery voltage from cranking it so much. Good testing is needed on this car to diagnose the concern.

dukejs66on Apr 28, 2018

Ok the shop said it runs on external fuel but when trying to run from tank it won't start

DaveJMon Apr 28, 2018

Yes, I understand this. This is why my response was what it was. Please read it again carefully. I am speaking of a fuel supply problem since it starts with fuel supplied externally at the engine.

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Join the conversation!

Popular Answer

What are the best BMW repair shops?

RepairPal Certified shops can diagnose and repair your 2002 BMW 745Li. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.

2002 BMW 745Li auto repair 2002 BMW 745Li estimates 2002 BMW 745Li questions 2002 BMW 745Li problems 2002 BMW 745Li recalls

1 Reply

Popular Answer

DaveJMon Apr 28, 2018

dukejs66on Apr 28, 2018

Ok the shop said it runs on external fuel but when trying to run from tank it won't start

DaveJMon Apr 28, 2018

Yes, I understand this. This is why my response was what it was. Please read it again carefully. I am speaking of a fuel supply problem since it starts with fuel supplied externally at the engine.

Reply in Thread

Join the conversation!