Hard Start Cold Weather

[watkd25]

Hello,

I have a 2006 Police Interceptor.

I have had the car since last May and everything was fine until it started getting cold out.

Early November, I started to get a cold hard start condition. Since then, I took the car to the Ford Dealership who was unable to duplicate the problem when the car was in but recommended changing the fuel pump as it lost quite a bit of pressure conducting a leak down test.

The day after getting a fuel pump, I still had hard start and there was a fuel leak. They replaced the gasket between the pump and the tank.

I then requested that the Battery be replaced and the original spark plugs be replaced and it didn't help.

I don't have any codes which makes this hard to figure out. But I have cleaned the MAF and that helped improve how the engine starts. But I still have a cold start issue that has now become a problem with the car sitting a few hours.

Also, when reviewing my code reader in Key On Engine Off (KOEO), I see that the fuel pressure will reach about 53 PSI and the slowly start to come down. In one instance it came down to 44 PSI.

When the car starts, I get a smell of fuel from the exhaust.

Any thoughts on what this could be?

Living in Arizona, the weather was in the 70s today and I noticed a little bit of a rough idle.

Mileage 123K

Fuel Filter replaced at 120K miles.

I have driven the car for 13,000 miles and I only use Top Tier Fuel.

Thanks.

[65comet]

I would say you have a dirty injector that is stuck open.

[watkd25]

Thank you for your response.

So is the resolution flushing the injectors?

I have most of the service records and I don't see that this has been done.

[65comet]

There are many things that can be done. I will tell you what I would do for my car and you can research what you will do. First, I'd put in a couple bottles of injector cleaner and some BP, Shell or other gas that is rated with good cleaners in it to see if that takes care of it after running a complete tank. Then if it is no better, I'd pull the injectors and clean them followed by bench testing how they are working. Replace any that are bad and use new O-rings. There are plenty of YouTube videos out there on how to do that.

[watkd25]

Originally Posted by 65comet

There are many things that can be done. I will tell you what I would do for my car and you can research what you will do. First, I'd put in a couple bottles of injector cleaner and some BP, Shell or other gas that is rated with good cleaners in it to see if that takes care of it after running a complete tank. Then if it is no better, I'd pull the injectors and clean them followed by bench testing how they are working. Replace any that are bad and use new O-rings. There are plenty of YouTube videos out there on how to do that.

Thank you for your response.

Just an update.

Car still has hard start on cold mornings.

I have scheduled the car for service at an affiliate dealer as I don't believe I am getting the service I am supposed to be getting.

Earlier this week, on the day that I set the appointment, I drove the car to a parking lot to check under the hood. It was in the upper 70s that day and when I got back in the car, with the engine running, I check the code reader and there was 55 PSI for Fuel Pressure. This tells me that the Fuel Pressure Regulator is not working the way its supposed to.

Today it was in the upper 70s and the car started on the first try.

I will update you in the coming days.

[watkd25]

One more update:

I took the car to the affiliate dealer earlier this month and the replaced the fuel pump. For three days everything was fine and the same thing started re-occurring.

Later in February, I took the car back and the problem ended up being the throttle body being dirty and also the Mass Air Flow Sensor was cleaned.

They also checked the fuel injectors and they tested good.

Thank you for your help.

[silicon212]

Did anyone ever replace the fuel filter? If the pump was replaced, one would hope they replaced this as well. Another possibility is the fuel pump driver module - this is in the trunk area on the rear seat bulkhead.