Originally Posted by MrBooby

If I cycle the key, it doesn't start right away. But it does help to shorten the cranking time.

Originally Posted by mdbrown

Leaky fuel injectors are not likely to be the issue here. The check valve is part of the fuel pump. Best indicator without going into the system is to turn the key to on but do not start the car, wait 5-10 seconds. Start the car, if it starts up right away every time (and has extended crank everytime you don't do this) then fuel pressure is the problem and the fuel pump is the most likely cause. If you wish to take it a step further then put a pressure gauge on the system. If pressure drops more than 1-2 psi then same conclusion. Replace the fuel pump.

Originally Posted by MrBooby

You were dead on.

I had it finally looked at today. The guy said that the fuel is leaking back into the tank, most likely due to a bad check valve. They measured my fuel pressure and said that it's reading at about 20 when it should be 60-something. Another thing they noticed is that cycling the key doesn't build any pressure, which he said was odd - so that's why it barely helps when I start the car. I would definitely like to get it fixed, so he's going to get back to me with the prices.

Only thing is that I would like to get the parts myself since I know a very good OEM dealer. Do you guys know what other little things I need to get besides just the pump? I understand that I need the filter as well, but what else? Please be as detailed as possible.

Originally Posted by mdbrown

Take a good look at everything before you start. If the fuel lines appear dry/cracking then plan on replacing the flexible fuel lines. The pump should come with a fuel sock. I'd probably replace the gasket at the same time. I don't have access to my repair books at the moment but I'm rather certain that you can get access under the rear seat.

You will need a very long screwdriver or, better yet, a very large set of channel locks or monkey wrench. Typically they are held in place with a large locking ring that will be tight and possibly brittle if it's plastic.

Originally Posted by MrBooby

How hard is it to do yourself? This is considering that the most labor intensive thing I've done was dealing with the valve cover gaskets.

I would like to get it done with no issues, since this is my daily driver and I can't afford to not have a car when I need it. What I mean by that is that I need to be 100% sure that I have all the required tools/parts on hand before I start. I ran into a bunch of little issues when I was doing the valve covers, so the job stretched out to over a month.

Originally Posted by mdbrown

Well, if you can access the pump underneath the back seat then I'd figure 3 hours or so. If you can't get to it under the seat (or trunk) then you have to drop the fuel tank, that's not a job you'll want to do.

Originally Posted by MrBooby

Went through the service manual and it seems like a pretty straight forward job, and the pump is accessible under the back seat.

Now about the safety precautions, do I need to do anything before I try to remove the pump? Such as running the engine dry with the relay disconnected? And is it better to have a full or an empty tank of gas?

Originally Posted by Hayk

Ever since I bought the car, it always took a while to fire up on cold starts. I put in a new battery(Lexus), since the previous one was dead, and it seemed like it helped, but the problem is in something else. It cranks hard and turns over, but it takes a few seconds to fire up. And it seems like it got worse ever since the weather got colder.

I also had a few rough idles in the first few weeks of driving, I haven't experienced one in over a week (possibly two). The car starts up fine if it's still hot and it hasn't sat for too long. I believe it gets bad after about an hour.

I've had a couple of CEL's. One was for an O2 sensor(P1153) - it popped up when I was already on my way with the engine warmed up, but it hasn't reappeared since I cleared it. Another one was for a misfire at idle with cylinders 2, 4, and 6 (P0300, P0302, P0304, P0306). I got another one today while on the highway and with the engine warmed up, but I'll only be able to scan it tomorrow morning.

Here are some things that I knew prior to the purchase

-I am the fourth owner
-The car had about 175,400 miles and is 13 years old
-Previous owner just recently put in a new alternator (possibly aftermarket)
-Had some minor engine work to pass inspection (replaced a valve of some sort)
-Both valve covers were leaking and had quite a bit of dirty oil built up around the seams
-Camshafts seals were leaking
-The front brakes were shot (seized calipers)
-The owner said that he used to get a CEL when the gas needle was below the half way point
-The car threw out some blue smoke on my first start up (it sat at the PO's house for a while), but I haven't noticed it ever since I started driving it.
-The previous owner doesn't know when and if the timing belt has been changed


Here are some things I found and/or fixed after the purchase

-Replaced the valve cover and spark plug gaskets
-Replaced spark plugs
-Replaced spark plug wires
-Replaced Intake Manifold Gaskets (manifold to head)
-Replaced Intake Plenum Gasket (manifold to plenum)
-Replaced all 3 coolant hoses
-Completely drained and filled the cooling system
-Replaced Engine Oil and Filter
-Overhauled the front brakes (calipers, hoses, pads, and rotors)
-Replaced the Brake Fluid
-Noticed a lot of gunk in the throttle body and the intake plenum
-Cleaned up the butterfly valve with some Brake Cleaner but the IAC might still be gunked up
-Replaced the PCV valve, grommet, and hose
-Replaced the Battery
-The three front ignition coil connectors have been replaced

-The rear sway bar links and bushings are shot and need to be replaced (the bar is loose and the rear end clunks over bumps)
-Noticed some old gas stains around the tank, especially around the rear sway bar
-The rear sway bar was corroded right under the gas tank stains
-Front sway bar links are on the way out, but are not as bad as the rear.
-The heat shield for the catalytic converter was hanging loose due to rust - removed.
-The car remote is still weak after replacing its battery and the car battery


Here are my guesses:

Idle Air Control Valve
Crankshaft and/or Camshaft Position Sensor
Low Fuel Pressure/Fuel Pressure Regulator

What do you guys think? I understand that I need some professional diagnosis, so I'll try to get somebody to look at it this week. I don't want to get stranded...

Originally Posted by Rushard

nk
Did you ever figure out what was your problem I have a 2010 lexus ls460 its now doing the same thing after having it almost 3 years now