Help me diagnose my problem

Synned

took tubgirl on a date and got banned
Mar 31, 2005
991
1
0
Philly
Okay I am having a power problem. After the car has heated up and has been running it runs like balls. It might even be the 2nd time I start it up but that doesn't make sense. The car will hesitate, say I'm trying to pull out of somewhere and give it a little throttle it will be really slow and hesitate. When the car is gold it feels amazing, I can burn out from a stop etc. So far I have done:
Plugs
Wires
Distributer cap and rotor
o2's
fuel filter
cleaned maf and iat.
What the heck can be the problem? Can my transmission be slipping? I also get horrible mileage and im pretty sure they are related. I really really want to get this fixed. Can it be the fuel pump? I heard when they heat up they get ****ty. I'm just about to take it to a mechanic, would they be able to solve the problem?

Thanks guys, any suggestions would be great.
 
Synned,

Since your symptoms are operating temperature related, it’s probably a combination of a bad ECT (Engine Coolant Temperature) sensor and a bad IAT (Intake Air Temperature) sensor.

Both are thermistors (variable resistors) and degrade over time in a high-temperature environment.

The ECT sensor performs the same function as a choke on a carburetor, and is located in one of the metal coolant lines that runs over the top of the engine near the distributor. It just screws in.

The IAT sensor is located in the intake air ducting after the MAF and before the throttle body, very near the passenger wheel well. It screws in as well, but needs to be indexed. Indexed means that it must be aligned so that the direction of air flow passes through the u-shaped housing around the sensor element, not at its side. You’ll see when you have one to look at.

The ECT is the most likely cause, but it could be a combination of both sensors.

Good luck.
 
I had a similar problem just about a year ago now. Ran like crap after warming up.

Mine turned out to be a loose spark plug wire. My theory is that it loosened up when hot because the connector expanded a little when it warmed up.

Does it ping at all? Have you checked to see if there are any codes?

Good luck and let us know your progress on figuring it out.
 
MLC Stang said:
Synned,

Since your symptoms are operating temperature related, it’s probably a combination of a bad ECT (Engine Coolant Temperature) sensor and a bad IAT (Intake Air Temperature) sensor.

Both are thermistors (variable resistors) and degrade over time in a high-temperature environment.

The ECT sensor performs the same function as a choke on a carburetor, and is located in one of the metal coolant lines that runs over the top of the engine near the distributor. It just screws in.

The IAT sensor is located in the intake air ducting after the MAF and before the throttle body, very near the passenger wheel well. It screws in as well, but needs to be indexed. Indexed means that it must be aligned so that the direction of air flow passes through the u-shaped housing around the sensor element, not at its side. You’ll see when you have one to look at.

The ECT is the most likely cause, but it could be a combination of both sensors.

Good luck.

This seems likely, because I know the car was in Florida it's whole life, never probably saw temperatures below 75*, so if those sensors wear out because the car was probably always running pretty hot down there.
 
Synned,

Here are the Ford part numbers:

Ford Part Numbers:

ACT sensor: F32Z-12A697-C
ECT sensor: F2ZZ-9G428-B

BTW, Ford calls the IAT sensor the ACT (Air Charge Temperature) sensor.

They are both about $50.00 at the dealer.

You can get them much cheaper at an auto parts place like NAPA, Auto Zone, etc. However, some on these forums have said that the cheap ones don't last.

I'd start with the ECT first and see if that makes the symptoms go away.
 
Thanks MLC i'll try those.
BTW, can it be the fuel pump? Someone told me that if the fuel pump is bad it'll act bad when its hot. I'll check fuel pressure I guess.
 
Synned,

Check the fuel pressure at the fuel rail B4 you replace the fuel pump. Replacing the fuel pump is a real PITA, because its inside the fuel tank.

If the pressure is OK, you don't need to mess with it.
 
So does anyone else have any suggestions? I went to get the sensors today but they were closed. >< I'll go back monday. Does everyone think that these are the problem? The car feels great on a cold start, but after warmed up it blows and hesitates to ****.
 
First, have you ran the codes?

Second, you are saying that once the car gets warm, it runs like crap? How long does it take for it to run like crap. a couple minutes, or until the temperature on the gauge gets to its normal spot?

I would lean towards your O2 sensors. They start working after appx. 2 minutes from initial startup.

But when the car starts running bad, you can get a gauge and check the pressure. That will tell you if it's the pump. Rev the motor while doing so and see if the pressure goes to 39.
Scott
 
mo_dingo said:
First, have you ran the codes?

Second, you are saying that once the car gets warm, it runs like crap? How long does it take for it to run like crap. a couple minutes, or until the temperature on the gauge gets to its normal spot?

I would lean towards your O2 sensors. They start working after appx. 2 minutes from initial startup.

But when the car starts running bad, you can get a gauge and check the pressure. That will tell you if it's the pump. Rev the motor while doing so and see if the pressure goes to 39.
Scott

The car runs like crap after it has been running for about 15 minutes. I already changed the o2 sensors, I think that it is actually when the engine gets hot. I was leaning towards the act/ect sensors because they measure the temperature of air coming in and someone advised me of this.