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Is It Worth Swapping My Ecu/afm Over To Fix My Problem?

TUF250

By TUF250,
in Engines & Forced Induction

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TUF250 Proficient

TUF250

Posted
Posted

Hi all,

I have a S2 Manual R33 GTS-T

Mods are:

3inch turbo bach exhaust, high flow filter (BMC), R34 SMIC GT-T, Walbro 255lt/hr pump and a full service inc timing belt, plugs etc.

I have been getting the R&R flat spot on cold nights (sub 10 degrees in melb at the moment) and the other night hit what I have since discovered is Air flow cut (maxing out the AFM).

The car runs std boost (5/7psi solenoid)

Some people run 12psi with no problems so I dont uderstand why mine is doing it?

I dont want anymore pwoer than this I just want it to be right with the standard boost (its a daily)

Is it worth swapping the ECU or AFM over? I have heard they can be hit and miss (some will carry on like mine and some wont?) or is it time for a remap?

I dont mind getting a remap but with these mods im suprised I need one>?

Thanks

Jason

paulr33 Grand Master

paulr33

Posted
Posted

i think you should do nistune or powerfc or safc and be done with it

nistune is undetacable, powerfc is easy to reverse if defected, safc is most annoying to remove

all of those should let you avoid the R&R, give some more power and better fuel economy

lachlanw Veteran

lachlanw

Posted
Posted

do you have a boost gauge ? or just assuming its still 5/7 ?

i have 2 friends in nz with series 2s with r32 actuators on them . 11 psi . and they go fine even when its snowing . maybe reset the ecu . and run some more timing

KiwiRS4T Grand Master

KiwiRS4T

Posted
Posted

Does your afm need a clean? Can you swap out with someone else to test? Get a boost guage - you can just run the tube through the door to get a reading but good idea to get one fitted anyway. You will benefit from getting a Nistune (not too complicated as you have a manual ) or look out for a cheap pfc. (... and of course a tune from a GOOD tuner).

TUF250 Proficient

TUF250

Posted
  • Author
Posted

Yeah I have a boost gauge (not an expensive one) but it does show 5 then 7.

I have cleaned my AFM before and have reset ECU. Timing was done by sabbaddin automotive when I had my timing belt changed.

Is this problem more likely to be my AFM or the ECU? I might change whichever it is over as I dont really want to get a tune just yet with such basic mods, rather wait until I have something more substantial.

Thanks for the replies so far

djvoodoo Experienced

djvoodoo

Posted
Posted
The more I think about it the more I wonder if the AFM is on its way out. Seems to explain alot, too many people dont have issues with their cars in the conditions that I am. thoughts?

Mate I am having exactly the same problem as you (but with an R34) running about 7.5-8psi on Greddy profec II, full service, coils, plugs changed and tested.

Bought a new AFM and just waiting for it to be delivered. Will let u kno if it makes any difference

gotRICE? Veteran

gotRICE?

Posted
Posted
i have 2 friends in nz with series 2s with r32 actuators on them . 11 psi . and they go fine even when its snowing . maybe reset the ecu . and run some more timing

Im running the same and dont have problems either. It has hit RnR a few times on really cold mornings, but that was in the dead of winter.

Id try borrowing a known working AFM before ordering a new one. A friend of mine bought a new AFM because he thought his one was bung. Turned out it wasnt. $600 odd down the drain.

If only he'd taken my offer of borrowing mine...

Toshi Proficient

Toshi

Posted
Posted

If your car is series 1 I think boost limiter problem ( R&R)

(series 1 and 2 bit different program. because series 1 do not have second throttle sensor )

If your car is series 2

Sounds like

1) change spark plunges.

2) replace coil pack.

3) change ecu.

TUF250 Proficient

TUF250

Posted
  • Author
Posted

it is a series 2. has new plugs and hae checked the coils.

I actually found a vaccume leak this morning. I have fixed it at work. Would this cause my problem? it was a decent split in the hose. Looking forwrd to the drive home to test it

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