Hi all,
Just picked up a new (to me) 2017 Ford Focus RS.
I owned a 2016 Fiesta ST for quite a few years, and the RS was always an aspirational car for me. Years go by, marriage, and a better job, and suddenly that dream is very obtainable. We needed a new car, and the idea of the RS as a daily starts to creep back into my mind.
I’ve been lurker here through the research and purchase process— all the information here has been an amazing help. Helped me pick a good vehicle and fix what may have been a mystery problem that plagued the car.
And this car seems to have an interesting story.
Found a very good deal on a 2017 Shadow Black with just under 17k. RS2 and moonroof. Had a full PPI and Oasis check, everything appears fully stock and in great shape (with a couple caveats). Wonder if anyone here owned her previously?
Looks like it had the head gasket done while on the lot in Jan of 2018. The original dealer must have been a jerk trying to mark it up, because it was special ordered and delivered in mid 2017 but not sold until Feb. of 2018.
Looks like the original dealer also botched the head gasket repair (Seems common from the stories here.), as the original owner was back in by 3k miles, and the entire valve assembly was rebuilt— new valve seals, VCT solenoids, timing chain, etc. The tech’s notes are extensive. Apparently had an issue with getting the timing right using the ford provided tools, and the CEL wouldn’t go away.
It was sold to a second owner not long after. Maybe too much of a headache?
History goes dark a bit, and then it comes to me. Looks like it was hardly driven— 13k miles since 2019.
I’m thinking— worst case scenario it was having intermittent issues that the dealer could not figure out. It wasn’t lemon law re-purchased, so it can’t be a show stopper. Probably a simple fix that’s difficult to figure out because this is a relatively rare build for Ford. Best case scenario it was fixed properly and this was just a weekend toy for the second owner, and they moved on to something newer and more exotic. I’ll take the gamble.
Purchase goes great, PPI is great. Maybe whatever was wrong with it at 3k really was fixed? Except by day 5 the engine light came on and idle became rough. Given the history I was obviously concerned. Ran the codes, came back with a single misfire event in cylinder 1, and a very odd P08B2-00 A/B correlation. Auto start stop also wasn’t working. But under acceleration and at higher RPMs everything is fine.
Before I started digging into replacing the ignition coils or even the PCM module, and going down a rabbit hole, I did some research here.
Could it be as simple as replacing the AGM battery? Has that been the issue the whole time? All the “tests” during the PPI on the battery came back green. But others here have found the strange PCM code is related to battery or grounding issues. Auto start stop is also linked. Maybe that accounts for the misfire too? Irregular voltage just causing electrical gremlins would fit the bill. It has been sitting most of its life not being driven. Could there be some kind of lurking issue in the battery related to how the BMS is trying to cope with an aging and degraded battery?
Open her up, and it looks like the battery is MotorCraft. Is it really possible this is the 6 year old stock battery? Seems like!
$300 and a new battery with a BMS reset later (thanks again forums!) and the car runs perfectly. CEL is gone, idle is smooth, auto start stop works—no more issues. Put in a 150 mile “spirited” drive upstate and back with an OBD logger in to make sure. Runs like she’s brand new. All codes clear.
So, thank you! I got a great deal on a low-mileage RS and was able to fix a lingering issue because of the collective knowledge here.
