02 3.9l lse hard start long crank smell

[dmeyung1]

I have a 2002 v8 lse with 92000. When i go to start it after it has been sitting for 20 minutes or more it cranks for a long tome before starting. When it does start it idles fine but has a strong fuel smell. There are no codes and no problems once it starts. However it starts up right away in cold weather. It seems like a flooding issue. The fuel pressure is within range but it does seem to bleed off quicker than most cars i work on when the engine is no longer running.. Unfortunately i dont have the specs on on fuel pressure runoff. I suspect the fuel pressure sensor/regulator. I dont believe it would be an injector due to the fact it never runs rough or misses once started and if it was the pump it wouldn,t give off a fuel smell in the exhaust once started. I was wondering if anyone has seen these sensors go bad or if there is another common problem with these vehicles. Thank you for your time.

[danielsatur]

Sounds like a BAD MAF sensor!
The MAF Heats the volume of Air,the Incoming Air Temp is measured,and
a signal is sent to The PCU for Air/Fuel control.

When you jump on the Gas pedal,is the car a little slow to react?

Wide open Throttle = Colder Air,the IACT sensor drops more voltage going to the PCU.
Closed throttle = Warmer Air,the IACT sensor drops less voltage going to the PCU.

Rob has a very good point!
Fuel filter,Air Filter,Air Box,and throttle body cleaning.
MAF sensor cleaner can be bought @ local parts store.

[shorod]

The MAF doesn't actually heat the incoming air. On hot wire MAF sensors there is a reference sensor element that is heated and the temperature rate of change of that element as the incoming air passes over it is used in the calculations, but the intent is not that it heats the air.

I've not yet replaced the fuel pressure sensor on my wife's 2002 LS V6, but at one point I suspected it as faulty due to a long crank and intermittant stalling issue. However, once I replaced the battery, that issue went away.

In addition to cleaning the MAF, you might consider cleaning the throttle body as well. When's the last time the fuel filter was changed? You may as well start with some typical tune up items, and check the age of the battery. If it is nearing 5 years of age, consider replacing it before tearing into the diagnostics too far.

-Rod

[dmeyung1]

The car does not stuutter when I get on the gas. It accels right away. It has a new battery and I an replacing the fuel filter today. I will clean out the throttle body today and the maf sensor. The reason I thought it was the pressure sensor is that when I disconnect the vacuum line from it to the intake it has fuel vapors in it and slight fuel deposits. Thanks for the input.

[Arjand]

Originally Posted by dmeyung1

The car does not stuutter when I get on the gas. It accels right away. It has a new battery and I an replacing the fuel filter today. I will clean out the throttle body today and the maf sensor. The reason I thought it was the pressure sensor is that when I disconnect the vacuum line from it to the intake it has fuel vapors in it and slight fuel deposits. Thanks for the input.

May have a regulator problem if fuel is getting into the vacuum line.

AD

[joegr]

Originally Posted by Arjand

May have a regulator problem if fuel is getting into the vacuum line.

AD

I assume that you have never worked on an LS? It doesn't have a return flow fuel system. Fuel pressure is regulated electronically. It does have a fuel pressure sensor that measures fuel pressure related to manifold pressure, so a leak from the fuel line to the manifold is possible, but it is very unlikely.

[sspruell77]

I am having the exact same problem with my 02 lsv8 and today when i started it up it seamed as if the engine was ideling high like racing I dont know anything about cars so im gonna take it to the dealer but would like to have an idea of what might be wrong. The car sranks slow and when it starts I can smell gas. Please help I am on a budget.

[shorod]

Since you mention the car cranks slowly have you checked the age of the battery? You may notice in post #3 above that similar issues (sans fuel odor) on my wife's LS went away when I replaced the battery. These cars are very sensitive to system voltage, and since the fuel pressure is electronically regulated I wouldn't be surprised if a weak battery could cause a fuel odor as well. Don't go by what a quick load test indicates, if the battery is 4 or more years old, you may as well just replace the battery now and see what happens. It won't be a waste of money.

-Rod

[GregA77]

Originally Posted by sspruell77

I am having the exact same problem with my 02 lsv8 and today when i started it up it seamed as if the engine was ideling high like racing I dont know anything about cars so im gonna take it to the dealer but would like to have an idea of what might be wrong. The car sranks slow and when it starts I can smell gas. Please help I am on a budget.

I've had what sounds to be the exact same problem as the original poster (temp making a difference on how long it cranks, gas smell, after 20 minutes of sitting, etc.). Brought it into the dealer and they couldn't figure out what the problem was. They replaced the fuel filter which did nothing and said the fuel pressure was fine. I'm going to clean the MAF sensor tomorrow and hope it makes a difference. I'll report back. Any tips to cleaning the MAF sensor I should be aware of? I just don't want to make any more problems for myself. thanks

[shorod]

Get the CRC brand MAF Sensor Cleaner and, if you don't already have them, the security Torx bits so you can remove the sensor itself from the housing. When spraying, be very careful not to let the straw touch the fragile elements.

And when that doesn't work, check the age of the battery as mentioned above. A new battery will cost you less than one trip to the dealer for diagnostics....

-Rod

[joegr]

If your LS is a 2000 - 2002 model, then you should also check your Idle Air Bypass valve when you have these symptoms. You can clean it, but if it is really gunked up, then you would be better off to just replace it.

[danielsatur]

The PCU needs the right signals for the air metering and fuel pulse during the cold start, or choking condition.

Turn the ignition key to the on pos for a couple of seconds befor startup!
This short time will also help clean keep the MAF sensor clean.

[joegr]

Originally Posted by danielsatur

...Turn the ignition key to the on pos for a couple of seconds befor startup!
This short time will also help clean keep the MAP sensor clean.

How the heck did you come up with that?
The 2nd gen (not sure about the 1st) doesn't even have a MAP. (It does have a BAP.)

[danielsatur]

Sorry! MAF sensor, not MAP sensor.

The MAF works like a self cleaning oven during initial startup for self cleaning.

[Jones006]

Lincoln LS hard start replace coil spark plugs still same problem .Found out it was the injector leaking fuel down into cylinder when car is off. whichever cylinder is misfiring Is the bad injector. this also can blow intake gasket when large amounts of fuel leak down into cylinder.