DebbieRX

Still looking for a fix.
I replaced the fuel pump...still not starting.

salimshah

Are you familiar with the fuel hose clamp and the quick-connector at the bottom of the engine bay, below brake booster [check the DIY thread on knock sensor]. Disconnect it see if you have built in fuel pressure.

Next step requires 2 people, on in the cab to insert and turn the key while the second observes fuel spewing out ... so exercise caution .. engine cold, no naked flame etc. Do not move the ignition to start.

Insert key and turn it to ON and the fuel pump should kick in and fuel should be pumped out. If you get fuel then move down stream to injectors. If not then apply +12v and gnd directly to the fuel pump. If the fuel starts to flow then check the following

Fuseable link
Fuses (AM2 30A, IGN 5A)
EFI main relay
Fuel pump
ECM
Wiring connections.

If not, then replace the fuel pump.

I have not worked on the Lexus fuel system, but my experience with Honda fuel delivery is that the electrical pump only runs when you have consecutive spark (this tells the engine is running). There is safety built-in, where in case of accident the fuel pump is shut off. I suspect that is what the ECM does in Lexus.

Lexus also has a hand held tester which can activate the pump ... shade-tree mechanic can directly feed +12v and gnd to the pump.

Salim

salimshah

[QUOTE=DebbieRX;8807372]Get Lexus Repair Manual ... no substitute, worth it weight in gold.

Salim

DebbieRX

This is a newly purchased fuel pump and the fuel pump is pumping fuel. I had two people with me yesterday to double check. Two in the back seat while I operate the ignition switch. Directly applying the 12v from the battery to the fuel pump wire harness in the back seat the fuel pump pumps fuel. With the key in the on position nothing happens, but with the key in the starting position the fuel pump kicks on and pump fuel but...the fuel will not travel to the engine. So there is fuel spewing from the fuel pump itself but, there is no fuel reaching the engine.

I will double check the fuses, fuseable link and relays...not sure if checking the ecm is something I can do myself, I will be back to post my findings.

salimshah

To the engine means to the quick connector ... then there seems to be blockage in the fuel pipe from the pump/tank to the connector.

Salim

supra_trd

iTrader: (3)

Change your fuel filter before? Im thinking about the ecu might be bad.

DebbieRX

Yes, It was changed when I replaced the fuel pump. Is there more than one fuel filter on this vehicle?

salimshah

I am totally lost.

If with a new pump and without using a jump of 12v to the pump, your fuel pump is pumping gasoline but you are not getting gasoline at the union/quick_connector [at the bottom of the engine drive side] then you have a blocked delivery pipe.

The instruction I posted clearly state how to check the electrical relay signal to the pump.
Then there are instructions to bypass the control and directly feed the pump 12v
One those are eliminated then it is the delivery hose.

Salim

DebbieRX

I was able to located the fuel connector underneath the brake booster. I disconnected the connector and there was fuel present in that connector. I also had someone attempt to start the vehicle as I watch to see if the fuel was indeed traveling to the connector and it was.

Two questions:
1. Does anyone know how to disconnect that fuel line from the the fuel rail?
2. Is it possible that the connector or the line that connect it to the fuel rail is clogged?

salimshah

Clogs are very unlikely.

You may like to check the pressure of the fuel.

The next choke points are the injectors ... just like the pump side, we have a electromechanical device.

You need to make sure the electrical signal is there and the injectors have been serviced.

Talking about possibilities ... more than one injector going bad at one time is low ... so I would expect some firing up of cylinders even if you were unable to hold idle.

Also there comes a time to rethink and not go too far down one path.

If you could get starter fluid* (not my preferred way) past the throttle butterfly, your engine should show some signs of life ... assuming the spark is timed right.

Salim

* check if the fluid is safe for your engine

Bobster999

I have told her that several times and in a PM, i think shes having trouble making that connection. When you remove the air tube from the throttle body and spray a shot of starter fluid, then she better at least try to start if not actually run for a second or two. If not, fuel is NOT your problem... or should i say, Not your only problem.

jsmith27

It there is a problem with the transponder in the key, you will have the no start condition.

DebbieRX

I replaced the timing belt and that fixed issue...thank you for sharing