Maxx1

So I decided to change the spark plugs on my Gfs 2006 Mustang GT today and ran into an unwanted issue. Currently the car has 109k and I'm pretty sure they're the original plugs before changed then out.

Step by step what I did:
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-Went to car wash and put a little degreaser to cleanup engine as it was pretty filthy. Hosed it down with the high pressure rinse, and drove home (about 10 minute drive). Car ran perfectly with just the minor sputtering @ about 50-65mph when downshifting, which is the reason why I wanted to swap out plugs.
-with compressor blew out any debris and water from around the coil packs as I didn't want any of that to get into the motor/heads when removing the plugs.
-began by removing the coil packs. Removed Screw. Unplugged coil connection. Did all 4 on one side.
-sprayed " PB Blaster" into spark plugs port to help loosen plug. Let sit for about 10 mins and slowly worked them loose until removed. Soaked up all excess of blaster spray with shop towel before fully removing plug, then continued to remove spark plug.
- Continued removal and replacement of the rest of the spark plugs.
- Double checked to see that I reconnected both the coil pack connector and the connection above the coil packs as I disconnected them to have less of a hassle when removing the coil packs. But everything looked good and connections were good. Not sure if it mattered as I didn't do it, but I did all this with both battery terminals connected.
- started the car and left it on while I picked up all my tools which is where I immediately noticed after about 30 secs that the idling speed was off and began slowing as it continued to run so jumped inside and tapped the gas pedal to try and accelerate it and it then slowed more until it shut off. The check engine light turned on before it shut off. When trying to restart it would turn on, turn over but wouldn't stay on.
I disconnected the battery with the intention of the computer resetting. After continued attempts to restart the car finally started and stayed on, BUT when I would step on the gas pedal no response. The motor would not go passed idling speed. I checked connections such TPS sensor and other connector in the inlet tube of the intake, and they were good.
I disconnected the battery again and restarted and same issue. There is no response from the gas pedal even when putting in drive or in reverse, it will not go passed idling speed.
Went online and checked to make sure the plugs were the right ones and they're good.
I don't know what to do.
I would greatly appreciate any help as I need to take the car in on Tuesday for a recall plus it's my girls daily driver.

Dino Dino Bambino

Sounds like the water from the hose has damaged either the throttle position sensor or the throttle butterfly actuator.
Check the output voltage from the TPS while a second person slowly depresses the gas pedal with the ignition on and engine off. Also check if the throttle butterfly opens.

Maxx1

First, thank you for taking the time to help I do appreciate the info. I'll definitely take this advice and look into the TPS voltage. Only question I have is what sort of setting should I put the voltmeter at?

Dino Dino Bambino

0-10V.

Rocket Ray

I had a problem one time with the car not running after I took off my cone-shaped air filter and put the stock airbox on. Car quit on the way home and couldn't get it to start. Turns out some rodents had found their way into the airbox and left some small seeds in there, eventually they lodged in the mass air flow sensor. Cleaning that solved the problem.

Possible there is water in the MAF sensor?

Maxx1

Thank you as well for taking the time to respond to this.
That's what it seems like, but what gets me is the fact that it worked fine until I parked the car when I started doing the plugs. I'm guessing it settled after just sitting there. But I'm gonna disconnect some sensors and put them in this moisture extracting stuff we use for small windows so I'm hoping that will help along with a cleaning of the throttle body.
🤞🏽🤞🏽🤞🏽
I'm gonna rent and OBD-II scanner as well, maybe that'll help me pinpoint the issue.
Unfortunately I was doing this about 10pm when I came across this problem so I was unable to go get one earlier.

bl817

what plugs did you use? and welcome btw.

Maxx1

I used Motorcraft SP-547. The car doesn't have any bolt-ons or performance add-ons so that's the reason I went with OEMs.

jt1991!

You've got water sitting in one of your sensors somewhere, or you shorted something out when you used the high pressure rinse. The water sitting inside one of your sensors is absorbing the voltage that should be going "through" the sensor connections. Hopefully that's it, and you didn't short something out. Now the problem is figuring out which sensor the water is sitting in. The bad lesson about this is that you can't wash a car engine, like you could in the 1960's.

tw1234

Did you use dielectric grease in the coil boots? If so I hope you just smeared it into the sides of the boots and not filled them. It is a dielectric grease and won't allow voltage to pass through it. Again check to make sure you've hooked up all sensor connectors, Electronic Throttle, mass air flow sensor at intake hose, etc.