Fuel induction service

is the fuel induction service necessary or suggested if the car is running fine. It is time for the 30,000 spark plug replacement according to service manuel and the fue induction service is being pushed at all the dealers.

My mechanic tells me that at that mileage, if the car is running OK (not hesitating or stumbling) any fuel induction service is a waste of money. Just do what your OWNER’S MANUAL says; I’m sure “fuel induction service” is not mentioned!

Today’s fuels have a lot of detergent in them to keep the fuel system clean.

We have a 1994 Nissan Sentra which is on its 3rd set of plugs at 125,000 miles and has never had any fuel system service and runs just fine and gets good gas mileage.

I agree 100% with Doc, unless you’re having a problem, the dealer’s just trying to clean your wallet.

It may or may not be needed. A lot depends on the type of driving you do. If your driving is predominantly short hop/stop and go then it’s at least possible that an induction cleaning can help.

It is entirely possible for a car to run fine with a sooted up induction system; or at least apparently fine. Any occasional idle hiccups, emissions flaws or subtle pre-ignition rattles due to sooted EGR passages, etc could very well be caused by a filthy induction system.

I mention this because I have seen more than one vehicle with a faint engine rattle or idle stumble of which the car owner was totally unaware of.

I tend to lean with ok here. Preemptive maintenance should produce absolutely no noticeable results. Intake fouling is a byproduct of multipoint fuel injection. No fuel wash to clean the intake from crankcase emissions that sink out in the pulse like environment of the intake (it’s not a whirlwind in there, folks). There’s not much to passively take care of that, but it’s not that big of a deal either. It will always be a recurring issue in every engine’s intake.

That said, I would use some injector cleaner with PEA (Regane-Techron-Amsoil PI) to assure that injectors, valves, and combustion chambers are clean of deposits. You’ll never notice fuel system degradation due to the advanced compensation protocols that the electronics provide. The typical long term owner can’t measure the effects of longer term degradation. There’s no distinct boundary or threshold of difference to trigger recognition.

…but beyond that, the last thing I would do is do a major upset with intake/valve deposits if I’m also throwing in a new set of plugs that I’m going to have in there for a long time. I’d do the service BEFORE the scheduled plug change …by a tankful at least.

This may occaisionally be true, but I bet 90% or more of the time, a symptom-free car with 30k miles has no need of a cleaning. And to me, ‘preemptive maintenance’ should at least show up somewhere in the owners manual. If not, I smell wallet flush.

My '88 Accord benefited a little (increased “base” idle) from getting its throttle body cleaned… at 200K miles.

If you want to get something extra and beneficial have the brake fluid changed at 30K.

The problem with using the owners manual as the final say-so is that the manual was put together by a consortium of engineers and marketing people; none of whom are mechanics and would likely starve to death if they ever attempted to work in the field.
Emphasis given to marketing, their job is to make the car owner think the vehicle needs little maintenance wise.

Consider those idiotic 100k miles spark plug intervals, fuel filter changes “when needed”, 100k miles or never transmission fluid changes, air filter changes every 30-50k miles (try that in OK after spring/early summer), and one of the most asinine and ludicrous recommendations of all; valve lash adjustment on solid lifter engines.

The recommendation there, by the previously mentioned engineers/marketing staff, is to “audibly listen and determine if they’re in need of adjustment”.
That recommendation alone should get the engineers laughed clean out of the building.

Even some things such as oil change interval recommendations are not always what is best for the car. But what do they care; even neglected, odds are the problems won’t surface until the warranty is up.

OK, but are you saying that every symptom-free car on the road should have an ‘induction service’ every 30k? For, say, $150?

I almost always agree with OK, but not this time. However I totally agree with his earlier post.

No, I’m not saying that at all. Only that it’s a toss-up and all cars should not be lumped into the same category.
In this case, the OP did not state anything about their driving habits, enviro conditions, or anything else.

It’s also possible that the emissions are not what they should be, clogged EGR passages could be contributing to a subtle and not noticeable to the driver pre-ignition rattle, and they may be totally unaware of it.
You would be surprised how many people drive around with problems far worse than this and are totally unaware of it.

A dealer I worked for once bought about 35 Chevrolet fleet cars. The common denominator on all of them was that they were all used for short hop driving and every single car had approximately 35k miles on it.
Every one of these cars was sludged and carboned up beyond belief as the dealer found out after the fact.

Every one of those cars was brought into the shop as what one could call “filler material” during the occasional slow spell and we had to remove the valve covers and intake manifolds. The valve trains were almost unrecognizeable and what does that have to do with induction cleaning? Nothing, except for the fact the intakes were gunked up just as badly for another reason and required a substantial amount of elbow grease to clean.

So in this case you have 35 cars with approx. 35k miles on each of them. Are these cars good candidates for induction cleaning? My feeling is yes.
In the case of the OP, my gut feeling is that it is not needed but it’s also not a given just because the car is apparently running fine to them.

OK, I see what you’re saying. Yeah, it depends, if it’s a rough 30k it could certainly be needed. Just not a sure thing.

Well, all of the dealers have OEM approved agents to treat given issues. Lots of “approved” stuff. So, while there are precautions about using additives and whatnot, it’s more to keep our ever increasingly ignorant population from screwing up …and more importantly, spending money outside the authorized outlets.