Valve spring recalls, bumping idle, low mileage, leaks, dealership, OH MY..
 

I could use some thoughts from you more experienced/knowledgeable mechanic sorts out there..


I like my dealership. They're nice friendly people, and the service manager isa joy to deal with.


My car has suffered the leaking cam plate cover (non-fixed twice by the dealership, so I fixed it w/ the Raceseng cover), the leaking timing chain cover (fixed by the dealership, but they didn't clean anything so I can't tell if it's still leaking or not.. car still smells after being driven or when stopped and idling), and now oscillating idle and gas mileage reduced aby about 20-25%.

It's at the dealership now. I have a Certified warranty until 100K/July 2019 on the drivetrain. They are aware of the spring recall, but there's no remedy yet. Car has not had the ECU flash TSB done, and they are going to do that. They want to do a throttle body service and MAF cleaning to the tune of about $150+, not covered by my warranty. Car has about 73K miles on it. My concern is, if those things are needed, why? What caused the fouling? Weak spring? Direct injection seals (thought I heard some slight occasional popping, but nothing like the obvious stuff posted here)?

Sooo.. advice? What should I expect from them, reasonably? What should I ask them to do/check?

I can change parts OK, but I stink at diagnostics. I'm not so sure they're a LOT better..



Thanks in advance..

Well, my mechanical expertise ended when they took away the carburetors.

However, from what I understand, I would suggest that you ask the dealership to:

* remove the under panels and clean the bottom of the engine compartment (to attempt to deal with the oil smell).

* have the ECU re-flash done (because of TSB).

* clean the MAF (because they can get dirty).

* throw them a crumb and have them clean the TB (why? Just because it might be dirty).

* why are valve springs weak - cause they were made of weak stuff.

* Misc - have you changed the cabin air filter?

* If you haven't changed the spark plugs, it might be time?


I hope you get your car settled down.


humfrz

Thanks, Humfrz. Yes, I had them change the plugs @60K, and the (MT) oil, diff oil, had the brake fluid changed at 30K and 60K, oil changes every 5K, etc... all at the dealership, even though I could have done all of it myself, just so they'd have a record of how well-maintained the car has been to avoid any discussions if a warranty issue should arise. I changed the cabin filter myself, and did the cam plate myself after their reseals failed.. with their blessing. Coincidentally (or not, but I doubt it), the gas mileage decline started immediately after they changed the plugs at 60K.

As they age, electronic throttle need to be cleaned.

Why?

Mechanical throttles used to have a separate idle control solenoid, electronic throttles control idle by turning the plate the other way from the "closed" zero point. The throttle bore is machined very precisely to allow for fine and gradual control of idle speed, however, all intakes get dirty from pcv fumes, after years it can create a step of deposits where the throttle plate usually maintains idle, resulting in unstable engine speed as the plate hunts around that point. Throttle cleaning is routine work on any modern engine.

Have them do their pcm updated that need to be done, have them clean up the mess they didn't clean up last time, and if you can't handle a shop rag and a can of intake cleaner, have them do the throttle and intake cleaning. (Hint: always clean an electronic throttle with intake cleaner on a rag, never by directly spraying it.)

Did you take it right back in? I agree, though correlation isn't always causation, something wasn't right after this.

Also, about gas mileage:

Keep in mind oil leaks burning on the exhaust can bias the oxygen sensor readings, as the amount of oil fumes under the hood changes the sensors reference to "outside" air.

bumping idle is normal AFAIK.

I hate that type of normal [emoji23]Sent from my Pixel 2 using Tapatalk