[SSgtjrobertson]

Just swapped in a new throttle body. Car idles fine then same thing. Limp mode right after I give it gas

So we are running out of 12 VDC inputs to the PCM.
First start with pulling fuse 32 (10 amp) and then test to see if 12 VDC is on the pin. If it's still there replace it and try fuse 34 (10 amp) and test again.

Let me know. Water damage is extremely difficult to trace.

 

[Kendall.RHD]

So we are running out of 12 VDC inputs to the PCM.
First start with pulling fuse 32 (10 amp) and then test to see if 12 VDC is on the pin. If it's still there replace it and try fuse 34 (10 amp) and test again.

Let me know. Water damage is extremely difficult to trace.

Okay, good news. We got some changes. I pulled fuse 34 and the voltage dropped to 5+VDC!!!!!

 

[SSgtjrobertson]

Okay, good news. We got some changes. I pulled fuse 34 and the voltage dropped to 5+VDC!!!!!

Ok good, now we are narrowing down the path of voltage.

The first two Items to throughly inspect will be the Sound symposer plug for water / corrosion (everyone just unplugs it and allows it to hang freely or worse stuff it into a plastic bag) and the other it the canister vent valve under the vehicle (which I believe I pointed you towards earlier due to an emissions related code)

Check the sound symposer plug and unplug the canister vent plug. Reinstall the fuse and test again.

Sorry if it seems like I've been slow to respond but I haven't forgotten about you.

J

 

[Kendall.RHD]

Ok good, now we are narrowing down the path of voltage.
View attachment 413641

The first two Items to throughly inspect will be the Sound symposer plug for water / corrosion (everyone just unplugs it and allows it to hang freely or worse stuff it into a plastic bag) and the other it the canister vent valve under the vehicle (which I believe I pointed you towards earlier due to an emissions related code)

Check the sound symposer plug and unplug the canister vent plug. Reinstall the fuse and test again.

Sorry if it seems like I've been slow to respond but I haven't forgotten about you.

J

Okay, I will get that done today. Do you happen to have a photo of exactly where and what the canister vent plug looks like. I crawled underneath but didn't see a connector when I first looked over that area. And also a photo of what the sound symposer plug looks like? Mine was deleted from the previous owner so I will have to locate it in the engine bay.

 

[SSgtjrobertson]

Okay, I will get that done today. Do you happen to have a photo of exactly where and what the canister vent plug looks like. I crawled underneath but didn't see a connector when I first looked over that area. And also a photo of what the sound symposer plug looks like? Mine was deleted from the previous owner so I will have to locate it in the engine bay.

The canister itself may have been contaminated if it pulled water into the vent, unlikely but anything is possible.

Or

This is the sound symposer plug.

 

[SSgtjrobertson]

The turbocharger wastegate solenoid is also low and on that circuit as well.

Just a heads up.

 

[Mzdrati]

Sorry if it seems like I've been slow to respond but I haven't forgotten about you.

J

Apologizes for lack of adequate response. LOL! This guy is just too much... I know nobody likes to see this picture, but this is the AGS plug on my relatively babied 2017 ST3 that was stored in a balloon. All that did was keep the moisture that collected in the plug, which eventually grew a layer of corrosion and turned on my "battery" warning light. If any of your plugs look like this- you'll have to either remove them, or clean them gently but thoroughly with a wire brush, blow them out with compressed air, and keep them dry.

 

[SSgtjrobertson]

 

[Kendall.RHD]

I come back to the forums with amazing news. I removed the evap canister and wiggled the connection while a friend watched the multimeter reading. It bounced between 5 volts and battery voltage. I found a bit of exposed wire. Removed and repaired. Car now runs and not in limp mode!

 

[SSgtjrobertson]

Glad to hear you got it figured out.

Stay Safe
J

 

[rob99rt]

I come back to the forums with amazing news. I removed the evap canister and wiggled the connection while a friend watched the multimeter reading. It bounced between 5 volts and battery voltage. I found a bit of exposed wire. Removed and repaired. Car now runs and not in limp mode!

And this is another example of why @SSgtjrobertson is an invaluable asset to the forums. Thanks again for figuring out what's wrong with another guy's car and helping us through the troubleshooting process.

 

[SSgtjrobertson]

 

[Kendall.RHD]

Glad to hear you got it figured out.

Stay Safe
J

Really, I can't thank you enough. I have beginner knowledge with electrical systems but your experience with the Focus ST platform is outstanding. It has been greatly appreciated.

 

[Mzdrati]

Really, I can't thank you enough. I have beginner knowledge with electrical systems but your experience with the Focus ST platform is outstanding. It has been greatly appreciated.

I work in the commercial nuclear power gen industry in the Northeast and Mid Atlantic states in the US and I've been a member of many technical and automotive forums. It's not often that I see anyone with the technical knowledge (and interest in sharing it) that SSgtrobertson has. His should be a paid position on these forums.

 

[SSgtjrobertson]

I work in the commercial nuclear power gen industry in the Northeast and Mid Atlantic states in the US and I've been a member of many technical and automotive forums. It's not often that I see anyone with the technical knowledge (and interest in sharing it) that SSgtrobertson has. His should be a paid position on these forums.

 

[SSgtjrobertson]

LMAO, I'm just an old cop. Self taught and severely dyslexic (no BS). The fact that I'm a former crayon eating jarhead is also a factor. Red is my favorite flavor BTW. All this alleged knowledge is from growing up poor & too stubborn not to fix my own stuff. In fact, and I can say this to be a completely true statement. Over my 47 years on this planet I have broken far more than I've ever fixed.

So it kind goes without saying that if a trained monkey like me can do this anyone can. In fact, I'm still waiting for someone much smarter to come along and read my posts like "wrong, wrong, all wrong. This guy's is a moron!"

But in till that happens I guess you're stuck with me.

J