2001 Lincoln LS fuel system issue w/ hard start

I have a 2001 Lincoln LS V8 that runs rich and no one can solve the problem that’s been going on for close to a year. The fuel sys pressure tests fine. The fuel regulator sensor has been replaced. First start in morning is normal but after that I need to give it gas to get it to turn over.

Also, car has a fuel smell. Any ideas?

So, first start in the morning, it start fine, idles fine and then drives fine? Then you park it and it will just crank and crank and crank without firing up? How long can it sit without having that problem? How long do you need to let it sit before it will start again?

And you smell fuel. When do you smell fuel? Only when you’re trying to restart it?

If the fuel pressure regulator was replaced then you’re probably looking at leaking fuel injectors. However, if there are signs that the car is running rich in general then you may new a new thermostat and/or coolant temp sensor.

Typically every start after the first one of the day, it will crank and crank and will only start when I give it gas. I’m not sure if I only smell gas at that time or even after it’s been running.

Just got the codes from the shop. P0133 and P0420

Earlier he said the pressure tests are fine but when I pressure him (no pun intended), he is telling me it should be at 35-55psi for my car and it is coming on around 32psi and ranges 27-33.

Now they are talking fuel pump.

Doesn’t rich mean it is using too much gas? (MPG are now terrible…@ 14) If so, how does a thermostat and/or coolant temp sensor cause fuel system issues?


Rich means too much fuel but it can also mean misfires. When referring to the smell do you mean a raw gasoline smell or an acrid smell coming from the tailpipe?

The fuel pressure is too low and I wondering if this low pressure is causing such a problem with the injector spray pattern and which in turn can affect mileage, performance, and so on.

When, if ever, was the last time the fuel filter got replaced? In the auto engineers infinite wisdom they put the filter inside the left front fender on the LS; out of sight and out of mind. The wheel must be removed along with the inner fender to access the filter.
If the filter is clogged it’s also quite possible for this to weaken and eventually kill the fuel pump.

The codes you were given point to an O2 and catalyst but this is unlikely to have anything to do with the problem with one exception. That would be if the converter is clogged to some degree. A clogged cat can cause poor mileage, acrid exhaust smell, lack of performance, etc. This could be checked with a vacuum gauge.

I have no idea why the fuel pressure issue hasn’t been addressed and hope some of this helps in some way.

As ok4450 mentioned, a new fuel filter would be an immediate first step, and if the fuel pressure is too low then the fuel pressure is too low. Someone should be watching what the fuel pressure does on a hot shut down and

How old are the plugs and wires?

The reason that the thermostat and coolant temp sensor are important is that the car has to run rich (higher than normal fuel in the mix) when it is cold. If the car never gets up to full temp or if the computer doesn’t know that the car is up to temp it will keep the mix rich. In other words, the coolant temp & temp sensor are crucial for fuel mix.


Just had all the plugs, etc. changed out due to misfires last month due to valve cover gasket leak. Was running on 5 cylinders.

As for the smell, I think it’s both. Smells like gasoline but also smoke comes out of exhaust from excess fuel, too.

I will pass on the rest of the info to my shop and see what they say. Thank you again.

Just wanted to mention that once it starts, it runs fine.

Mines doing the same thing what was causing the gasoline smell ?

My info says fuel pressure specs are 30 to 65 PSI depending on demand.