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lexpert
lexpert, Lexus Master tech
Category: Lexus
Satisfied Customers: 2100
Experience:  Master Certified with lexus, 8 years experience with Lexus
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2002 Lexus ES300. 200k miles. Car is running very poorly,

Customer Question

2002 Lexus ES300. 200k miles. Car is running very poorly, missing and lack of power. Engine Codes: P0174, P0171, P0330, P0776. Help.
Submitted: 1 month ago.
Category: Lexus
Expert:  Gunvir Singh replied 1 month ago.

Hello, let me review your request. Please stand by.

Expert:  Gunvir Singh replied 1 month ago.

Does the engine misfire at idle or when driving?

Customer: replied 1 month ago.
both, it seems like poor fuel pressure. It wants to die at idle but doesnt. Little to no power up a hill. Same problem cold and hot, idle and driving.
Expert:  Gunvir Singh replied 1 month ago.

Has any repairs been done underhood recently?

Customer: replied 1 month ago.
no, This is my friends car and he says no.
Expert:  Gunvir Singh replied 1 month ago.

The codes P0171 (system lean bank1), P0174 (system lean bank2), p0330 (knock sensor), P0776 (shift solenoid B performance). Out of all these codes P0171 and p0174 can make the engine run rough at idle. Need to start by checking for vacuum leaks underhood.

Customer: replied 1 month ago.
ok i will do a look over. Any areas that have common vacuum leaks?
Expert:  Gunvir Singh replied 1 month ago.

Since both the banks are affected check main air hose to the throttle body for cracks, booster vacuum hose and also aroung intake manifold area. IF no vacuum leaks found then next step is to check the fuel pressure.

Customer: replied 1 month ago.
ok, be about 30 mins or so.
Expert:  Gunvir Singh replied 1 month ago.

Ok.

Expert:  Gunvir Singh replied 1 month ago.

Hello, just checking if any updates?

Customer: replied 1 month ago.
I looked and found a few small leaks and one major one off the booster. I repaired all, disconnected the neg battery for a few hours. Started it and it is still missing. It runs better and I only ran it for a few mins.Should I take vac readings? Drive as is? Or test fuel pressure?
Expert:  Gunvir Singh replied 1 month ago.

If no more vacuum leaks are present then check the fuel pressure. Need to make sure that is with in specifications before you start driving.

Customer: replied 1 month ago.
How do I do that?
Expert:  Gunvir Singh replied 1 month ago.

On this vehicle the manufacture has not provided a fuel tester port. The fuel pressure will need to be tested at the fuel pressure line with help of a closed fittig and fuel pressure gauge. The pressure is supposed to be 44-50 psi.

Expert:  Gunvir Singh replied 1 month ago.

Hello, just checking if any updates?