Possible Fuel Issue. Need Some Advise

[clacey]

I have had, what I thought was a "cold start" issue with my 91 LS400. I've tested many of those components and all is well.

I now believe it is a fuel issue. Here is the deal:

The time it takes to crank seems to be related to the amount of time the car has been sitting.

Example:

If the car sets overnight, it takes about 3-4 secs to start in the morning.

If the car sets several days, it might take 6 secs to start the next time.

Once you start it, for the first time in the morning, you can immediatly kill the engine and it will start immediately all subsequent times.

It seems as though the fuel system, very slowly looses pressure over time, as the car sits. There is no gas visibly leaking under the car. The only other thing I noticed is that the evap canister is rusting and it smell like gas. I'm not sure if that could have anything to do with it.

Anyone have a clue? I don't think the injectors are leaking. Is this something I can test? Does the fuel system stay pressurized when the engine is off?

Thanks,

CL

[90LS400Lexus]

Perhaps a weak fuel pump or clogged fuel filters?

[VMF]

i changed fuel filters and it didnt help in my case:) it is still takes around 1.5-2 secs to start mine:)

[jzz30]

i think thats normal.

[clacey]

I checked my injectors yesterday and they were not leaking. I wonder if it could be the fuel pressure regulator.

CL

[UCF3]

Has anybody changed their starter, alternator, and fuel pump. I know mine is getting old and it takes 1.5sec to start my LS on a cold day. During summer it's immediate. On the other hand, my SC takes close to 3secs and does that, even during summer.

[clacey]

You might trya good throttle body cleaning. Mine has 213,000 mi and everything was really gunked up, including the cold start injector.

CL

[MICKEYLEXUS]

I have had, what I thought was a "cold start" issue with my 91 LS400. I've tested many of those components and all is well.

I now believe it is a fuel issue. Here is the deal:

The time it takes to crank seems to be related to the amount of time the car has been sitting.

Example:

If the car sets overnight, it takes about 3-4 secs to start in the morning.

If the car sets several days, it might take 6 secs to start the next time.

Once you start it, for the first time in the morning, you can immediatly kill the engine and it will start immediately all subsequent times.

It seems as though the fuel system, very slowly looses pressure over time, as the car sits. There is no gas visibly leaking under the car. The only other thing I noticed is that the evap canister is rusting and it smell like gas. I'm not sure if that could have anything to do with it.

Anyone have a clue? I don't think the injectors are leaking. Is this something I can test? Does the fuel system stay pressurized when the engine is off?

Thanks,

CL

just a test :D

[91ls400]

Where is the throttle body? How do you remove and clean it?

[clacey]

The throttle body is the top part or layer of the engine. It proudly displays the Lexus badge. The air filter element connect into it. I bought some Carb and choke cleaner and some shop rags. I chose to remove mine. It takes about an hour. There is a post on here somewhere that shows how to clean it without removing it. I only removed mine to check the cold start injector which is in the bottom of the intake assembly.

CL