Log in

View Full Version : 2004 F-150 Throttle body


sackettjess
Jul 9, 2007, 10:00 AM
Hi, I made the mistake of pressure washing the engine in my truck and now it won't start. The throttle body I was told could be the reason because it probably got wet. When it is unplugged, my truck will start but the gas pedal does nothing. No matter what you do to the gas pedal it will not accelerate. Help! Thank you.

TxGreaseMonkey
Jul 9, 2007, 12:38 PM
Remove the Throttle Position Sensor (TPS) connector and allow it to dry out. It's very easy to short out sensors, alternators, and ECMs by getting things wet. If you want to clean your engine, it's best to spot clean it by hand. Otherwise, you risk big problems.

If allowing the TPS to dry out does not solve the problem, I would attach a scan tool and check for codes.

sackettjess
Jul 10, 2007, 06:17 AM
Thank you, I will try this. Do you think it should already be dried out since it has been a week since it got wet?

TxGreaseMonkey
Jul 10, 2007, 07:45 AM
Probably. I would check for codes. You may have to check/replace the TPS.

sackettjess
Jul 10, 2007, 12:36 PM
Thank you so much. Since everything else appears in order, I will take the chance of purchasing a new TPS. I have faith.

TxGreaseMonkey
Jul 10, 2007, 02:15 PM
You might also disconnect the negative battery terminal for a while (resetting the PCM) and force the computer to relearn certain things. It's worth a try.

Josiah
Jul 27, 2007, 04:25 PM
You might also disconnect the negative battery terminal for a while (resetting the PCM) and force the computer to relearn certain things. It's worth a try.
TXGreasemonkey. I too have a 2004 F-150.

My truck has a problem starting, I just replaced the starter, not the problem. When I start my truck the cylinders do not fire, it sounds like the gas has not reached the chambers. It takes forever to fire up, I feel like I'm driving a beater! I'm pretty mechanically inclined so any help will be tried. When it finally does turn over it almost stalls out then gets up to running. I've changed the fuel filter, maybe fuel pump? Maybe injectors?

TxGreaseMonkey
Jul 27, 2007, 05:50 PM
Josiah,

. Ensure battery is fully charged.
. Check all under dash and under hood fuses with a test light or multimeter. Here's how:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563-3.html#post252145

I recommend these first two simple steps, so you can establish a "baseline" of what is known-good.

. Check for codes--I suspect the solution will come from this effort (e.g. possible misfires, due to one or more bad coils on plugs).
. Replace platinum spark plugs, if they have 50,000 miles or more on them. Only use the exact Motorcraft plugs that came in the truck.
. Ensure the inertia switch to the fuel pump is connected--reset if needed.

Josiah
Jul 27, 2007, 05:57 PM
Josiah,

. Ensure battery is fully charged.
. Check all under dash and under hood fuses with a test light or multimeter. Here's how:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563-3.html#post252145

I recommend these first two simple steps, so you can establish a "baseline" of what is known-good.

. Check for codes--I suspect the solution will come from this effort (e.g., possible misfires, due to one or more bad coils on plugs).
. Replace platinum spark plugs, if they have 50,000 miles or more on them. Only use the exact Motorcraft plugs that came in the truck.
. Ensure the inertia switch to the fuel pump is connected--reset if needed.
As far as fuses go, what do you think could be blown? I'll check all fuses. I have an Edge Programmer which tells me codes as I receive them and what they mean, no codes. If you're talking about the fuel pump cutoff switch by the fuse box, I know if that was turned off it won't start period, I can get it started and it runs great when it finally starts. The spark plugs, that will be a problem. There is a HUGE without a recall or TSB on spark plugs for the 04+ F-150. Everyone is breaking plugs off in the heads, and it's costing everyone thousands in labor. 1 out of 15 guys seems to have no problem changing his sparks.

Let me know what you suggest, other than the fuses which I will go out and check.

TxGreaseMonkey
Jul 27, 2007, 06:49 PM
. How many miles do you have on your spark plugs?

Change them when the engine is "stone cold." I use a 15" flexible T-wrench to remove the plugs on my 2000 Taurus with a 3.0L Duratec aluminum head engine. This wrench gives you a good "feel." If needed, apply Kroil or PB Blaster to plugs and allow to sit for a while. Once you remove the plugs, apply half a pea-size drop of high temperature nickel antiseize compound (e.g., Motorcraft XL-2, 8 oz.) to the lower threads, allowing rotation to spread the compound as the plugs are tightened. Using too much antiseize compound allows plugs to "coke" in the holes. Torque plugs 20% less than specs, because antiseize compound is a lubricant and you don't want to strip the threads by torquing to specs. ASME convention is to assume dry, unless specified otherwise. Since antiseize is being used, adjust accordingly. Remove platinum plugs every few years, in order to keep them from seizing in the head.

. Check for spark.
. When you turn the ignition key to ON, do you hear the fuel pump run and the fuel rail pressurize? If not, check/replace the Constant Control Relay Module (CCRM), usually mounted next to the battery. It controls many functions, including fuel relay, on Fords. Disconnect negative battery terminal first. Fuel rail must be pressurized, in order for the injectors to work. Here's how you want to start any modern-day gasoline vehicle. Turn key to ON, allowing fuel pump to run and fully pressurize the fuel rail. Normally, a light on the instrument panel will go out after several seconds, telling you this has happened. Then, turn the key to START. It fires off much faster and easier this way.
. Check air filter and MAF Sensor.

My gut is spark plugs. Your truck is too new to have major problems and it's not throwing any codes and apparently not blowing fuses.