View Full Version : Throttle response

07-24-2007, 12:16 AM
My 04 has just passed 15,000 miles. It feels like a little bit of snap has gone out of the throttle response....not bad, just a very slight hesitation. Maybe I am just getting used to the car's power. I went from a stock 04 GT to the Cobra....so it seemed like a rocket at first. At any rate, I was thinking of having my local Ford dealer check the plugs and put the car on the computer to see if there was any ignition or fuel mixture issues. Would the average Ford dealer have someone competent to do this, or should I consider a performance shop? The dealer "was" an SVT dealer at one time. Thanks.

07-24-2007, 07:04 AM
Things to inspect:
1. Air filter, replace it if you still have the original filter.
2. Cleaning the MAF sensor will restore the throttle response. Use either MAF sensor cleaners or Electrical parts cleaners only. Do not use a throttle body cleaner to clean the MAF sensor.
3. Instpect the throttle blades of the throttle body (back side that you cannot see when the throttle is closed). Recirculated gasses from EGR, PCV system and heat tend to form deposits and varnish on the throttle blades which inhibits air flow when applying slight throttle.
4. Replace PCV valve (low cost item).

Recommended item to have changed: fuel filter. Should be done every 16k miles.

Ford would probably recommend the MOTORVAC process. Not sure if this really works or is worth the high cost.

07-24-2007, 04:43 PM
Thanks Aussie,
I just washed and lightly re-oiled the K&N air filter, so I think that is okay. I would never have thought to clean the MAF or the throttle body blades. I think I can do that without screwing it up. Would your typical auto supply store have the proper cleaners?

I hate to admit this, but I don't know where the PCV is hidden on this car. Where will I find it?

07-24-2007, 09:51 PM

If you take that coating off of the blades you will hate life. It can cause idle and drivability issues if you do. If you clean the throttle body becareful.

Get rid of the k&n the oil from that filter can get on the maf and cause it not to read properly and can cause you to have a lean condition when you dont want one heh.

As for throttle response your just getting used to the car. Get a pulley and a tune :thumbsup:

07-24-2007, 10:05 PM
Take this for what it is worth...most people who re-oil the K and N filter will put too much oil on it and have the problem described above by Blue Blazes. It's worth the extra dollars to buy a new one where the oil is applied by a machine where the amount is almost always the right amount and no over oiling will occur. JMHO! :)

07-25-2007, 07:18 AM
I would agree about the K&N filter, over oiling will cause MAF sensor issues. That can be cleand with electrical parts cleaner since that will not harm varnishes used on motor windings and the special type of wire used on the MAF sensor without leaving an oil residue like most throttle body cleaners.

There is a special coating on the brass throttle body blades and proper care must be taken. Any of the solvents intended for use as a throttle body cleaner may be too agressive and most will remove paint. The worse thing you can do is to remove it and soak it in solvents (never do this). I would try the water first on a soft rag. I have found that Ether works extremely well and evaporates quickly if used sparingly. I have not suffered from drivability issues after cleaning the throttle body with Ether (starting fluid). I did this last year, and so far the throttle body has remained contaminant free. Best to avoid the harsh chemicals as much as possible since Ether will also attack paint and coatings as well as the common solvents used in throttle body cleaners (primarily acetone) but there are other compounds far more aggressive such as organic solvents which will remove everything.

07-25-2007, 07:24 AM
PCV valve is on the top side of the valve cover on the drivers side opposite that of the oil filler cap. Look towards the fire wall.