2017 Ford Expedition Acceleration Problem

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cranchy

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Hello,

I recently purchased a 2017 Ford Expedition Limited with 192k miles and am experiencing some issues. When accelerating past 56 mph, the RPM shakes when it exceeds 2000, triggering a flashing engine light and misfires in cylinders 5 and 6. I've replaced all spark plugs and coils with original Ford parts, but the problem persists.

Currently, I have error codes for both bank 1 and bank 2 catalytic converters,
after reset the codes and after 500 miles disappeared and recorded an O2 sensor code for bank 1, sensor 1. I also have a P0299 code for a turbo under boost condition and replaced the turbocharger intercooler valve. I can hear the turbos working, but pressing the accelerator past 60 mph still results in misfires and a flashing check engine light.

I suspect a clogged catalytic converter or a leaking exhaust manifold gasket, and I plan to check for leaks in the turbo air hoses and consider the fuel pump as well.

in the morning when starting the car it starts shaking but after 2 minutes when the rpm reaches 600, it becomes calm and not shaking.

Additionally, the transmission was functioning well initially, but after changing the fluids and resetting the learning tables (including a throttle body replacement), I'm now experiencing hard shifting from 1st to 2nd gear ( it happened before when resetting the tables and took about 2 months to shift normally and after changing the fluids I reset the gear again but still have the same issue after 1 and half month ), with shifts at 2500 RPM in lower gears and 2000 RPM in higher gears.

Any suggestions would be greatly appreciated! I can provide live data if needed.
 
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JasonH

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Did you check for codes? The vibration, misfires, and mileage make me suspect timing chain stretch. It's not really a stretch, just excessive wear in the links that makes the chain long. The P0299 code is a low boost code the vehicle throws to protect itself when other issues are present. I suggest checking the plug gaps first, because that's relatively easy. I think Forscan has a Mode 6 diagnostic that can check timing, but beyond that you have to pull the passenger side valve cover to check the tensioner extension. My exhaust manifold leak didn't throw any codes. If it's leaking, you'll know. Especially when cold, as you can hear the whistling from the exhaust gases escaping. It sounds like insect in the engine bay. Sometimes it seals itself when the manifolds get hot, but mine got progressively worse over time.
 
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cranchy

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Did you check for codes? The vibration, misfires, and mileage make me suspect timing chain stretch. It's not really a stretch, just excessive wear in the links that makes the chain long. The P0299 code is a low boost code the vehicle throws to protect itself when other issues are present. I suggest checking the plug gaps first, because that's relatively easy. I think Forscan has a Mode 6 diagnostic that can check timing, but beyond that you have to pull the passenger side valve cover to check the tensioner extension. My exhaust manifold leak didn't throw any codes. If it's leaking, you'll know. Especially when cold, as you can hear the whistling from the exhaust gases escaping. It sounds like insect in the engine bay. Sometimes it seals itself when the manifolds get hot, but mine got progressively worse over time.
thank you for responding
when I got the car the codes were
p420, p430, p0299, and when accelerated misfire code appears at cylinders 5 and 6 and then disappears ( it was in the summer and it was hot )
now after the weather started to be cold and after resetting the codes and after using the car for about 500miles ( never drive over 65mph) I only got the O2 sensor bank 1 sensor 1
the engine is quiet and can't hear any sounds happening when have a problem with the timing chain but I will check it too

I can't hear any whistling sounds from the manifold but will check if can see any signs of leaking at the manifold

I read this post, i think it looks like mine so I just ordered pcv valve and O2 sensor and will try them to check if there is any improve


thanks again for reponding
 

JasonH

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Also check the plugs and wells for oil contamination. The valve cover seals leak, which lets oil into the plugs wells and may result in fouled plugs. This can contaminate the cats with unburned fuel and oil, hence the cat codes.
 

sandbuster

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Just a thought that hasn"t been mentioned yet - a vacuum leak. Here's a (very) old mechanic's way to check for a vacuum leak. While at idle using a mildly combustible spray, like carb cleaner, spray around the top of the engine and along manifold gasket to see if you get a significant rise in rpm. It's normal to get a mild rpm increase but if you do have a vacuum leak big enough to throw those codes the spray will detect the leak. Good luck.
 

Catodechile

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Hi, I just bought a 2017 Limited with 100K and got misfires while stepping on it at full throttle. Went to the Ford dealer to get a scan and see the codes but didn´t get service unless I left the car for the day with them. I left and dived into this Forum. My previous Expy was a 2013 V8, and never had a problem with it. I am now planning the whole maintenance and I am learning a lot. Thank you guys!
 

tjwoyke

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I'm wondering if you ever got this fixed. I'm having the same issues and was going to take it in for evaluation. Any conclusions?
 
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cranchy

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Hi
I changed the pcv valve,i noticed improvement in the acceleration but still have the misfiring,
I noticed one stud of the exhaust manifold is broken but I can’t notice a leak,
I think the catalyst converter is damaged so i ordered another one and waiting to replace it.
I think to replace the fuel purge too because i feel the problem is there is a pressure in the engine that causes the problem may be from the bad converter or the fuel pruge
 

tjwoyke

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Sounds great...thanks for the update. There doesn't seems to be one cause for this problem, so it's a fun one to figure out. Hope the catalytic converter does the trick.
 

MidnightBruce

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When I first purchased my used 2016 with 41k on the clock, it would occasionally misfire and low power under WOT. After a lot of reading it felt like there was a massive ingestion of fluid from the intercooler. I did the 1/64th inch weep hole in the driver side lowest point of the intercooler to prevent oil and moisture buildup. There's a lot that comes out of that hole, but does not create a boost leak. I have a paper towel was that I shove under it and change that towel (diaper) every oil change. Never have had a misfire since I did that or low power. Plugs gapped at 0.027 as well. 16 mpg average. Also changed to Delo 5w40 full synthetic oil (I like the additive package) at 60k miles and it's helped keep the cold start rattle at bay. No other engine work has been done. Very reliable and consistent. I drive it like I stole it, and spray Lucas GDI cleaner before every oil change (5k miles). Due to the amount of idling my wife does for school pick-up I have changed my OCI to 150 hours. Best of luck finding the source of your misfire.
 
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cranchy

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Thank you for sharing your experience
I read alot about that, but it says it works with ford f150 from 2011 to 2014, for the expedition it spouses that issue solved but I will try
I bought catch can too some people say it may decrease the problem but waiting the weather to hot enough to install it
 

MidnightBruce

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Thank you for sharing your experience
I read alot about that, but it says it works with ford f150 from 2011 to 2014, for the expedition it spouses that issue solved but I will try
I bought catch can too some people say it may decrease the problem but waiting the weather to hot enough to install it
I thought our trucks had the same motor as the 2011-2014 F150's, which would make sense. I also removed the extra plastic shrouding the front of the IC to give a bit more cooling area. Since I drilled the weep hole I am no longer concerned about condensation building up.

Catch cans work best if they have the dual valve for when under vacuum and then under boost on these motors. Best of luck and hope you get warmer weather for installation time. Love these Ecoboost motors and I truly believe they have lots of life in them.
 
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