Mechanics

P-71 BAD FUEL INJECTORS?

2003 Ford Crown Victoria

Engine Mechanical problem
2003 Ford Crown Victoria V8 Two Wheel Drive Automatic 125000 miles

Beside the LCM and multifunction switch troubles I have got another little problem:

When I bought the car about 2 years ago (100.000 miles) I realized that the engine sometimes started to sputter at about 30 - 50 mph when you press gently on the accelerator within this speed range but his didn ´t happen very often.

I also realized that the car engine doesn ´t run all round on sloping roads at 30 mph. This happens e.g. when you drive down a hill in the city without using the accelerator. But this was sometimes hard to sense.

I tried to solve the problem by changing the spark plugs, the ignition coils, the air filter and fuel filter. It didn ´t help. No problems when you push the pedal to the metal or under/above this speed range.

I also tried a fuel system cleaner and this seemed to
improve the driving ability for some time but I can ´t
say it for sure.

Maybe the California Highway Patrol used bad fuel? They put on 100.000 miles in 3 years on that Ford.

I kept on driving and ignored the problem. But after about 25.000 miles and during the last few weeks the problems have become bigger:

The Ford sputters now much rougher within the described speed range and this happens very often.

It seems that the idling is also slightly affected.

Are these symptoms for bad fuel injectors?

Your answers are really appreciated!!!


http://www.2carpros.com/forum/automotive_pictures/348741_Ford_Crown_Vic_bearb_2.jpg

Avatar
Frontpushbar
April 26, 2009.



I think if you solve the more serious issue of electricl circuit malfunctions, these symtoms will clear up. Have you scanned for codes yet? Do it even if the check engine light is off, it may have freeze frame data that can help. Also check this out.
You may have a vacuum leak, get a can of spray throttle body cleaner, spray the vac lines and maniflod area, when the idle changes, youve found the leak! You want the engine running and spray on the outside but do direct the stream onto the hoses, if it is a vacuum leak, the engine idle will change speed, then you have detected a leak, repair the vacuum leak and see how it runs! If that doesnt do it, you may need a new idle air control valve, it's bolted to the throttlebody.

Merlin2021
Apr 26, 2009.
Thanks for your fast answer!

Has my sputter problem within the speed range from 30 to 50 miles anything to do with bad fuel injectors or is it probably just a vacuum leak?

Tiny
Frontpushbar
Apr 26, 2009.
It could be a symptom of either, or a completely separate issue. Isn't car repair fun? Unfortunately shops are often in the same position--you don't know for certain if a component is an issue until you replace it. Merlin is absolutely correct--scan this system for trouble codes and freeze frame data. It sounds like you are pretty mechanically competent--if you took this problem into a shop, you'd probably spend as much as if you invested in a scan tool. I recommend buying OBDII cables and the software so you can use your laptop to communicate with your car. This stuff can be had fairly cheap, 200-250$. I just bought this software and am pleased with the results so far. I think you will go a long way to solving your problem when you can view data streams in real time.

Tiny
Atkaparking
Apr 30, 2009.
Repairing is fun thats for sure!

During my 8 hours highway driving time to The Tyrol
this weekend I have noticed the following symptoms: The first 3 hours driving were fine. The sputter
happend just once within a construction zone
at 45 miles.

I have to say that I went between 60 and 100
miles per hour (the speed limit is about 85 mph on
Austrian highways and I also drove through parts
of Germany - they don ´t have any speed limit).

I stayed most of the time at about 90 mph.

After 3 hours the sputter became heavier.

The engine sputtered from 40 to 100 mph during
acceleration phases with half throttle. At 40 mph
it did it really rough and it didn ´t stop until I reached
85 mph.

Even at acceleration phases with full throttle I noticed
an uneven acceleration movement. It didn ´t sputter
but the car didn ´t accelerate in a smooth way - it
seemed that it didn ´t accelerate with full power.

That was the first time that this happened between
50 and 100 mph.

The same on the way back to Vienna: The car sputtered just once during the first three hours and than the sputter became harder
during the speed range as described above.

It sputtered really hard at 50 miles when the highway
went up a hill.

I have read on the internet that the 2003 Ford
interceptors are famous for fuel pump failures.

Maybe it ´s the fuel pump?

OR

Maybe the PCV valve is blocked?

Ford recommends to exchange the PCV valve at
120.000 miles. I have not done it yet.

To be continued.

Tiny
Frontpushbar
May 3, 2009.
If no codes check the pump pressure, and hook up so you can drive it and watch the gauge. PCV isnt a bad idea either.

Merlin2021
May 3, 2009.
Thanks for your answer!

PCV valve is already ordered.

Fuel pump pressure is going to be tested as you
recommended.

Results will follow.

Tiny
Frontpushbar
May 3, 2009.
I'll be watching out!

Merlin2021
May 3, 2009.
I replaced the PCV. No improvement.

The engine started to sputter really rough yesterday
and it did it all the time. Suddenly the "check engine"
light came on for the first time.

I hardly managed it to drive to a mechanic who has
got a U.S. Ford code scanner.

It read: "engine misfire cylinder 1"

He erased the code and made a testdrive with
linked scanner. The code appeared again.

Then he put a professional fuel system cleaning fluid
in the tank and the sputter symptoms improved in a
way so I was able to drive home.

He said that he had the same scanner code
indication with a Pontiac Trans Am and after
the fuel injector replacement the problem was solved.

I have already changed igniton coils, spark plugs,
air/fuel filter and PCV valve.

So the problem seems to be the fuel injectors.

I have already ordered 8 new ones.

I ´ll keep you informed.


http://www.2carpros.com/forum/automotive_pictures/348741_Ford_Crown_Vic_bearb_3.jpg


Tiny
Frontpushbar
May 16, 2009.
I replaced the fuel injectors today and now the
engine purrs like a cat - no sputter anymore!

The problem is solved.

Tiny
Frontpushbar
Jun 3, 2009.


http://www.2carpros.com/forum/automotive_pictures/62217_Cop_Car_2.gif


On the road again, I just cant waitr to get on the road again! How about the other problems?

Merlin2021
Jun 3, 2009.
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