2002 Lexus GS300 cranks but wont start.
 

Hey guys i have a 2002 gs300, and a couple weeks ago i went to work car was fine. When i left work my car wouldnt start it would crank and crank but not turn over. So i had it towed home and didnt mess with it because i was busy. Now i have some free time so I've had time to look at it. Right so first thing i did was change the starter. That didnt work still did the same thing. So i took some starter fluid and spayed into the intake, still didnt start but it poofed and caught fire, so im guessing i have spark but no fuel. So i changed the fuel pump, fuel pressure regulator, fuel strainer and put it back on. Nothing again. I can't hear the fuel pump turning on either when i turn the key. Im not sure whats going on. What else could it be? Also when i put my key in the security goes off so its not that. Im thinking it might be like the ecu/ecm or maybe fuel delivery. Also checked the fuses, all look fine. Any ideas? Thanks *Edit* Also my fuel gage says half a tank, but when i pulled fuel pump out it was like a quarter tank. I put some gas in so now its about halfway but the fuel gage didnt change

If it was cranking, the starter was clearly not the issue. Would have left that alone. Not sure how it sounds cranking though. Is it a normal cranking sound or is it kinda fast and flat sounding? As easy as it is to remove the upper timing cover, Id take it off and make sure the cams are turning with the crank. Then its also easy to line up the timing marks and verify timing. If thats fine, use a spark checker to verify spark. Sounds like it probably does since you heard a change when spraying fluid. Is there coolant in the radiator? Had a 97 SC300 in the shop a week ago that was a no start. Sounded like no compression. First went to the belt, but saw the belt turning and timing was fine, but then saw it was empty on coolant. Fried the engine.

Check those basics first and let me know what you see. Then we can get into testing igniters and fuel controls, etc.

Ok so its like a normal cranking sound, it also dims the lights when cranking thats what made me think it was the starter. Timing belt is fine, all the belts are tight. Its definitely getting spark there just seems to be no fuel getting to the engine. Coolants fine i top it off once a week. Oil is fine too just had that changed on the 3rd of January. I check that at least once a week.

Since you already had the FUEL pump replaced and know how to access it,
Let's start here:

--- Check if you have power going to the FUEL pump. (CRANKING and/or KEY ON)
--- It's gets it power and ground from the FUEL pump ECU.

it doesnt make any sound when i crank the car, nor just turning the key i dont think its getting any power

Quick easy look before checking for loss power/ground on the FP.
Check the 15 AMP EFI FUSE if its good. (should have power w/ KEY ON) <-- i know you said it looked "good" but you need to check if there is power flowing thru that fuse.
Then check the EFI relay
Location same as the EFI 15 AMP fuse.
See if its energizing. (When key is put in ON position, relay should click)
The ECU energizes this relay which then sends power to the FUEL pump ECU.
Swap it with a know good relay if in doubt, maybe the HORN relay if it works.

checked all the fuses for fuel and starter. They are all in order and have power

The GS has a fuel pump ECU... it only pressurizes when told to. Static will have no pressure, you have to turn to START for the pump to pressurize, or be running under a low/medium/high load.

There's another thread on the fuel pump, and fuel pump ecu. The easy way is to measure fuel pump voltage while the key is in the START position (should be battery voltage).

The long version is, while the ignition is in the START position...

* is the ECM outputting properly on the fuel pin, telling the FP ECU what to do?
* is the FP ECU hearing the signal, and telling the fuel pump what to do?
* is the fuel pump hearing the signal, and producing pressure?

If while you have the ignition in the START position, and the fuel pump is receiving 12v, and the fuel pump is outputting 45-50psi of fuel... it's not the fuel pump.

If the EFI fuse was bad the security light will continue to flash during cranking.

If you are getting no fuel pump pressure at all I would suggest checking your Fuel pump ECU, cam and crank sensor. preferably with an oscilloscope.
The cam and crank sensors may or may not be within resistance tolerance per service manual but they become weak over time.
Cam and Crank sensor signal is required for the Engine ECU to turn on the fuel pump ECU circuit. The Main ECU sends signal to the Fuel Pump ECU to adjust it's output speeds.
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Ok sorry for the long response. I had a big job come through. Yesterday i fixed it. After checking all fuses and power going to everything i determined the problem was at the fuel pump. So i decided to take a look. Turns out they gave me the right pump but missing pieces. I took a look at the old one and used the O ring on it and put it on the new one plugged her in and wala it starter. Thanks so much for the help guys!