Fellow i am new to this group and wanted to see if I can get some help. I bought a used 2018 expedition XLT 4x4 with 104k miles. The vehicle idles rough and the transmission is jerky as well. The first start of the day is usually the roughest, if I dont start driving the vehicle right away it misfires so bad that i start getting the blinking CEL. I hooked up to a scanner, it shows a P0305 (cylinder 5) misfire. I have changed the spark plugs, moved the coils around and even the fuel injectors but the misfires stays in cylinder 5. I even done a compression test (results attached) which looks good to me and also did a borescope of the cylinder which looks fine too. I was hoping if someone in this group can help me guide what I can do next to identify the problem? Thanks
2018 Expedition Rough Idle and Jerky transmission
- Thread starter sikikh83
- Start date
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techdude99
Full Access Members
To confirm, there's a 20 PSI variance between the highest and lowest readings?
The two lowest readings are adjacent cylinders?
The two lowest readings are adjacent cylinders?
Did you swap the DI injectors? Or did you only swap port injectors? Cold starts rely solely on the DI injectors only until about 120 degree coolant temps are met. Once temps reach around 120, you’ll hear the HPFP shut off and it switch to port injectors. Very obvious on these engines.
FWIW you can’t swap DI injectors without replacing seals. With over 100k and unknown service history, I’d drop about $600 on rock auto and replace all 12 injectors, 6 plugs, and 6 coil boots and call it a day!
FWIW you can’t swap DI injectors without replacing seals. With over 100k and unknown service history, I’d drop about $600 on rock auto and replace all 12 injectors, 6 plugs, and 6 coil boots and call it a day!
And as far as trans, get up underneath and check fluid level with trans temps over 200. 17 and 18 models are known to have low fluid from the factory if never serviced before.
Wouldn’t hurt to drop that trans pan and do a service. Then get set up with Forscan and reset your transmission adaptives and see how it feels.
After that, long as everything is good, get a tune and the trans will treat you nice!
Wouldn’t hurt to drop that trans pan and do a service. Then get set up with Forscan and reset your transmission adaptives and see how it feels.
After that, long as everything is good, get a tune and the trans will treat you nice!
SyndicateZ
Full Access Members
Id bring the thing back to where u got it from and get a refund.
