kj217

my 02 C4S hesitates in partial throttle,, rpm also fluctuates sometimes on warm starts shortly before it stabilizes,,

cold starts,, full throttle are all ok,,

given that my 4S is RUF supercharged (assume its 996TT),,
what can be the problem?

100plus

How do you clean the injectors on our cars? I would like to perform this cleaning also

logray

On the hesitation, since you have the supercharger, it's anyone's guess. There are some supercharger guys on here, maybe they will chime in.

To 100plus question, to clean injectors in order of least effective to most effective. a.) run quality gas with fuel additive already in it (i.e. techron). b.) add a fuel additive i.e. stabil/techron/seafoam on a regular schedule. c.) remove the injectors and send them to a specialist for micro cleaning.

feds

Some guys on the Pelican Parts BMW R1100S (boxer engine) forum have messed around with RC injectors and also sent out their factory injectors for cleaning and calibration/matching.

http://www.rceng.com/Fuel-Injector-Cleaning-P43C0.aspx

dennis hiip

Redline S1

Byprodriver

That's where I send mine for cleaning & testing.

kj217

fuel additives won't hurt engines with blowers?

Macster

Absent any symptoms that point to dirty injectors just buy top tier/high quality fresh gasoline and drive the car.

I am still surprised that after say 40 or more miles of high way driving how both of my cars, their engines, perk up. And I drive 60 miles a day to/from work at mostly highway speeds so it is not like these cars get treated to short trips, grocery runs day in and day out.

If you want to 'try' an injector cleaning with the injectors in place, buy a bottle or two of Techron and use according to directions on the bottle. I like to change the oil/filter after using Techron. (I only use it once every 2 years or even less often to try to give my 02 Boxster now with over 253K miles a bit of edge when I take it in for its smog test.)

Real injector cleaning involves removing the injectors from the engine and installing them in a fancy box which pumps cleaner through the injectors until the spray patterns of all injectors (chances are though just one or two will be 'dirty' and have an abnormal/stunted spray pattern) look like they should look.

Sincerely,

Macster.