Car Tune-ups - what exactly happens during a tuneup?

Question

For the average car tuneup, what should the mechanic do under the hood?

Answer 1

The basic tune up my shop does is change the spark plugs
check the wires
check the cap and rotor button (if equipted) and coil
check the condition of the fuel filter
check the condition of the PCV
check the condition of the air filter
check the belts, and fluids
recomends a fuel system treatment
recomends a throttle body cleaning

and tahts what I can remember off the list, remember, every shop is different, thats what my shop does.

NEVER RUN DIESEL IN A MODERN GASOLINE ENGINE. YOU WILL DAMAGE SENSORS AND OVER ALL DAMAGE THE ENGINE.

Answer 2

Depending on the cost of the tune up. Going for a cheapy will get you the minimal amount of work.
It is also variant on the type of engine.
Age of engine
In general what should be done every time the hood is opened:
Fluid levels an eyeball inspection(coolant, brake fluid, washer fluid, battery levels, transmission oil level check, engine oil level check)
(With some cars valve cover is removed and valve lash is checked and set) then a compression check,
Hose and belts eye ball /hand check of condition and tensions.

Average tune up these days is:
Air cleaner check/replaced
Plug wires condition check/replace if cracked.
Plugs removed, inspected new plugs are gapped and installed
Distributor cap removed
Points replaced(old cars) and gapped, rotor replaced and new distributor cap.
Coil voltage output check visibly(blue spark)
Ignition timing adjusted and set.

I may have missed something. It is hard sitting in front of a computer compared to standing in front of an engine.

Answer 3

Depends on the year and model of car....

My Ztec Focus Tune-Up is Replace spark plugs,
Check Air Filer , replace if needed
Check, Plug wires, Drive belt, Look for oil leaks and coolant leaks

Added things Cleaning fuel injection system ( but I do the Techtron in the Gas for that)
Replacing the Fuel filter every 15000 miles...

My Vette motor... Replace Spark plugs, Cap, Rotor,
Adjust timing, and Carb Vaccum
Check Plug wires, Oil and Coolant Leaks replace anything looking bad or leaking.
Replace Air Filter and Fuel Filter.

ETC... Depends on year and model for what needs to be done as preventive Servicing....

Good Question.... Just need more info....

Answer 4

good question. My theory is very little that actually matters.

I would say change air filter, maybe change oil, maybe change spark plugs.

It might just be a fuel system tune up, where they clean the gas system, from deposits caused by clean fuel additives (which cause more pollution, but that is another story).

I wouldn't do this. They are expensive. I doubt you'll get out of it what you are hoping. Only in rare circumstances would a car need this. Try running a little diesel through it. Not much, maybe 20 oz in a full tank of gas.

Answer 5

i own a repair shop,and we pretty much do it all when we tune one up,,i always change the oil,,and lube it,,change spark plugs,,wires distributor cap,,and button if needed ,a new gas filter,,and air filter,,a timing check,,and set if possible,,check all the belts,,replace if needed,,and test drive it,we pretty much do it all here ,we don't leave nothing to chance that could go wrong with it,,and leave you stranded some where,,other shops don't agree with my way of doing things,but that doesn't bother me,,i have a good steady list of clients,,who appreciate this kind of service,,and have become to expect it of me,,but that's what a good tune up should be,,good luck hope this help,s.

Answer 6

First you need to look at the mileage and how hard you drive.Most tune-ups are just spark plug's and fuel filter change.After you get about 30,000 miles you should also replace plug's wires if needed
and transmission fluid and filter along with coolant.even if you have platinum plugs you should never leave them in longer than 30k or leave fluid in that long in trans ,coolant,axles .

Answer 7

Plugs/wires, cap/rotor/coils packs,fuel filter,air filter, air filter, oil and filter, PVC, check vacuum lines, check belts and hoes. Do it your self and save your money for gas.

Answer 8

change the spark plugs, spark plug wires, check the distributor and adjust timing if needed... im sure there's more i haven't covered.

Answer 9

air filter, oil and oil filter, fuel filter, maybe sparkplugs and grease the front end. check all lube levels such as tranny and rear end! most of them just say they check all that.

Answer 10

You should do it yourself, its not that hard. Change the motor oil, oil filter, spark plugs,and air filter.