Scotty,
I have a 2014 Ford Focus Titanium with Flex Fuel and about 85k miles. I'm having an issue right after startup and warmup. Right after putting the car in drive after either starting it up or letting it warm everything is fine until I let go of the gas and the tach goes down a little to like 700rpms from usually hovering in idle or 1st w/brake at 850rpms. When it drops that little amount the car starts to put like it's dying out but it catches itself. After the car has been driven for a while it doesn't happen anymore. I was using regular gas but switched to e85 and it seemed to help a little bit but my MPGs are like 40% less. However using e85 the car feels like it has more power. I thought maybe it was bad gas so I ran it through a bunch of tanks to no avail. It's not throwing any codes as of yet. What can I do here and what should I look for? The other day it got a little dangerous and I pulled out of where I lived as I misjudged how close a car was and the rpms dropped and I gave it a lot of gas and it bucked really hard. I've watched every video you've done on my car. Please help, thanks in advance.
God Bless,
Brandon
The thread wouldn't let me edit but I bought the car with like 75kiles and the previous owner said some engine mounts are bad as it does vibrate like crazy. But it gets almost 40MPG with regular gas on the highway and like 25 to 29 in the city. With e85 I get wayyyy worse. I've never had any error codes and otherwise it drives nice. I love the hatch and it can really move in sport mode and handling is decent also. I'm just a little worried about this idel slash stutter issue. Thanks
You're supposed to get way worse mileage with E85, that's not an issue.
@chucktobias make sure you put your answers down below. Thanks.
Holy moly! After changing the sensor the car drives like a new car! How could that stupid coolant temp cause so many issues? It must have been failing for years. When I bought the car it shook like crazy and the last owner said it was bad motor mounts. But after changing the sensor it only vibrates a little bit, kinda like a car with almost 90k miles. The hesitation is gone and it runs so much better. I'll update after some long term use but this is amazing! Scotty have you ever seen anything like this before? I never had issues on the highway and I would get almost 40MPG so maybe the system was running super lean? I'm curious to see how it does now on MPG. I just can't explain how different it's running now. No more every plastic part (which is a Focus is everything) vibrating to death. Just wow! Super easy to change also.
Okay first just check for vacuum leaks could be a vacuum leak. If not that try my video make your car run better with a little spray cleaner where you can clean the meth sensor and the throttle that often fixes it
Scotty,
Thanks, I'll check for vaccum leaks and I'm sorry what's a meth sensor? I searched Google but didn't find anything on that. I bet autocorrect changed what you wrote, lol. I'll report back once I check. Thanks again.
MAF sensor.
How could that stupid coolant temp cause so many issues?
the stupid engine temperature is only one of the most important pieces of information the computer uses to control your engine.
700 rpm’s at warm idle is still ok. Ford does have a lot of a TSBs on motor mounts. Do you if the Mount was replaced? Bad mounts can make your car feel like a rough idle. Easy thing to do to check if it’s a bad mount is to slightly jack up the engine by the oil pan, make sure to use a block of wood on the jack first. Start up you car and put it in gear. If the rough idle goes away your issue is your motor mounts.
OK, I checked for vacuum leaks as in your video scotty, nothing found. A new wrinkle has appeared. I got a hard code via the check engine light. It was P0116 which says online engine coolant sensor failure. OK, so could what I've experienced above be related to this or is thus a new code altogether? It seems like an easy thing to change so I'm going to do it. I'm just worried that this has nothing to do with the stutter?
I bought the sensor and im waiting till my engine is cool later this afternoon to change it. I also want to thank everyone who has chimed in, I really appreciate what everyone does here. Thank you thank you thank you.
Aside from codes, live data may shed more light on what's going on if that sensor doesn't help.
Scotty can that error code cause issues like I've experienced? Thank you
A bad sensor can tell the computer that the car is cold, forcing it to give it a richer mixture than necessary and run rough. Same thing if the signal is bad telling the computer it's warmed up when it's not. Hopefully, a new sensor will solve your problem.
We are glad it worked out for you.
Have you ever seen a coolant sensor causing such a severe reaction. It must have been bad for years literally. I'm blown away.
OK, I changed my spark plugs and this is what they look like (see images below). Only one looks worn worse on the tip but that same one has bad rust on the hex. Well they all have rust on the hex which I don't understand but the tops look worn normally? Remember I also had a bad ECT I replaced yesterday. After changing the plugs the car even idles smoother now, which with the ECT change makes it feel like a new car, lol. But should I be worried about these old plugs and what does it say about the engine condition. Thank you in advance.
https://ibb.co/r00dvhJ
https://ibb.co/55325B0
It appears that water somehow got down into the wells the plugs sit in and corroded the hex portion of the plug, which really shouldn't affect the plug performance. I'd try to find a reason for the water, or heavy condensation, and try to mitigate it. Obviously, new plugs are in order. Did someone try to clean the engine bay with a pressure wash at some time in the past?
Doc, the car was sold in an estate sale, a guy bought it from the estate, kept it for like a year and then sold it to me. It had great records for maintenance (paperwork in the glove box). I'm thinking either the estate sale people or the guy himself when selling cleaned the engine bay. That is my theory anyway? How do the plugs look as for wear? I'm guessing they are the OG plugs as I looked through the glove box maintenance and I didn't see any plug changes. Also the plugs are Ford, the same exact ones I replaced them with also. Do the plugs tell you anything about the engine? There was no oil on any of them. I tried to look at those plug guides but to me most of the plugs look the same so I'm not sure if something was wrong via and image. You guys see this stuff more often and can maybe tell me the real deal. Thank you again.
I can't see the detail on the insulator very well but it doesn't look like much wear on the grounding electrodes. Looks OK to me.
Doc,
So they look good to you, meaning you think the engine was taken care of? Oddly, if you look at the far left sparkplug in the images (via the link above) the spark plug looks further worn down than the other 3. I think the rust was like you said and someone washed the engine bay with high pressure. The car runs better now since the sensor and new plugs so I'm happy. I watched a lot of videos on spark plugs and what they say about your engine but most of the types all look the same to me. I was watching a video from scotty about e85 and he said some customers get 20% less fuel economy but I'm seeing like 40% less. So I've been mixing it with regular gas to keep my engine clean plus it's cheaper, lol. If anyone can take a look at the old spark plugs below and let me know what they think, thank you.
https://ibb.co/r00dvhJ
https://ibb.co/55325B0
I am looking at the pictures again and it looks like the grounding electrode is hardly worn at all.
So what does that mean? Also did you notice how the first plug was worn more than the others, what could cause that? Thank you.
I couldn't see that.
Hello, I'm having really bad issues now. I changed that thermal sensor, the top engine mount, mass air flow sensor, Vapor Canister Purge Solenoid (was ticking). I had gotten codes p025A, P0103 and U0109 when he check engine light came on which is why I changed the mass air flow sensor. Right before the codes I noticed some rough idle which would come and go. Now when I checked my car with Oreilly's ODB scan tool a while back when I changed my engine mount I was getting fuel pressure at idle of 560 to 580 psi via the scan tool. Now when I checked I was getting 390 to 405 psi. Is that important? After I cleared the computer and cleared the transmission module the codes didn't come back. But now when I take off I get strong hesitation and stutters. When I first start pressing the gas it actually feels like all acceleration stops for a split second. Once I get up to speed it goes away. I drove it on the highway and it felt ok. Also it seems my MPG has gotten a lot worse. And I'm using premium shell gas for the past 3 fill ups. Please any help as this is making it hard to drive. The transmission also isn't the problem (i think) as when I floor it (scrubbing the clutches) it works fine. I just got a ELM ODB2 for Forscan to see more live stats. Thank you in advance.
Codes are:
U0109
LOST COMMUNICATION WITH FUEL PUMP CONTROL MODULE
P025A
FUEL PUMP MODULE CONTROL CIRCUIT / OPEN
P0103
MASS OR VOLUME AIR FLOW A CIRCUIT HIGH INPUT