Mechanics

ROUGH STARTING

2003 Lexus SC 430

Engine Mechanical problem
2003 Lexus SC 430 V8 Two Wheel Drive Automatic 57000 miles

I bought my Lexus SC430 used in 2008 with 53k miles. Stored both winters. Took out of storage in March. Ran perfectly until early May 2010. Began to start very rough - crank for 6-8 seconds. Sometimes would start then, other times only on the 2nd try. Once started, no problems. Took to Lexus dealer and they diagnosed low pressure from the fuel pump - suspected check valve - had it replaced. Took home and brought it back since it was not fixed. They diagnosed 3 leaking injectors so those were replaced along with a fuel dampener. Did not fix problem. Now they say that 4 of the remaining 5 injectors - which were not leaking when tested last week - are now leaking. Want to replace injectors saying that there is a lot of sediment in the gas tank that has caused this problem, so they will also clean the gas tank, replace the fuel screen, the fuel pressure regulator and fuel filter.
They say that the sediment could have been in there before I bought it since these are typically stored for half the year.
This is getting very expensive. Does this diagnosis make sense? It is hard starting about 25% of the time.
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Jangregg
June 30, 2010.




Hi jangregg,

Thank you for the donation.

The diagnosis does makes sense to a certain degrees. I believe not all the injectors are faulty but the dealer ship is not taking the risk and recommends all to be replaced.

There is a possibility some injector cleaner can solve the problem of the injectors leaking.
Leaking injectors would cause uneven running at idling, does that happen after starting?

The difficult starting due to low fuel pressure is what I believe to be the real cause for the difficult starting. I would suggest rechecking the fuel pressure. There is apossibilioty there is a leak in the pressure line and if it is inside the fuel tank, it would not be noticeable.

When vehicles are stored for long periods, sediments can build up over time. The sediments could be brough in by fuel so you need to be careful where you fill up.
Cleaning the fuel tank should be the first priority.

KHLow2008
Jul 2, 2010.
It only occurs during starting, runs perfect once started.
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Tiny
Jangregg
Jul 6, 2010.
If there is any fuel pressure leak, starting would be difficult. After starting, the engine would run well but once you turn the engine off and wait a while, starting becomes difficult again. If that is the case, then the cause would most likely be pressure leaks.

KHLow2008
Jul 6, 2010.

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