Sputters over 6000 rpms
 

Hi my rx7 started sputting at 6000 rpms and it feels slow. At 11psi it felt ok but as soon as i pushed the boost to 14psi it started to sputter. I have two guesses

1-Problems with my top feed spark plugs
2-problems with fuel pressure (maybe fuel filter, i have never replaced it) over a year with the car.

My car has power fc, walbro pump,v-mount ic, intake, catback, etc...... Vacuum lines seem ok. Boost levels were normal. No knocking.

you have to look @ your PFC setup maybe..
there could be several tuning reasons for that mess.

f.e. does the PFC have a fuel cut, too.
How did you increase the boost?
With pfc or another extra boost controller?

If you have a standalone boost controller, make sure that in the PFC you set the desired boost onto the right numbers for your higher boost!
If you work with PFc you have two options.
1st increase desired boost
2nd increase precontrol dutycycle. If you do it wrong you can increase boost alone with the precontrol dutycycle (which normally is there, to reach the desired boost faster).
In that case, you are running higher than desired boost (+X) and PFC perdorms a fuel cut.

So to make a long story short.

Go and take a look @ your PFC Commander and lok if your desired boost level is set up properly. Which yould be:
On standalone boost controller: Set desired boost level in PFC higher than 14PSI
On boost controlling with PFC: Set desired boost level to 14PSI half your precontrol dutycycle. Then increase it slowly until everything is perfect.


I hope that is your problem.
Good luck and I hope that helped!


RE gards

Marc:icon_tup:

check your grounds and plug wires.

Does it do it when you rev the engine with the clutch down at still? or only at WOT in a certain gear? Or at 6krpm regardless of how much gas you give it?
Could be plugs, leads, coil, fuel...amongst others. I had a problem similar recently, mine was coil.

TK.

ignition breakup, you will need to get a hks twinpower www.rx7store.net

^ +1

just checked the spark plugs. look very bad. just order a new pair of trailing and leading plugs. also bought a new fuel filter just to be safe. pretty sure thats it. thanks any way.

get an ebay ground kit too. if it still runs like shit, you are going to need a twin power based on how much boost you are running.