Hi all,
My 2003 996TT has the GIAC flash. On Pump mode it is registering .5 BAR max when it used to be 1 BAR. I've checked and confirmed there are no boost leaks and when you drive the car you can hear the DVs (their the billet upgrades) release at .5 BAR so it seems like an ECU issue. If I set it back to stock it does the same thing (stops at .5). No errors are being registered and outside of this, everything else appears normal.

Is this a common issue with the GIAC flash? I remember reading something about resetting this some time ago but I can't find the thread now. Any suggestions?
Thanks.

 

try disconnecting the battery for 10 minutes and go try again.

 

Also plug in an OBD2 reader to see if there are any soft codes being stored. This would also cause it to go into limp mode and preset to 0.5 bar

 

Well guys, even though I was not seeing any errors it looks like it was going into limp mode for a reason. Reset the battery and started up. Started to roll out and PSM/ABS lights went on and the idle was a little up/down. When driving it it stutters a little.

It seems like a MAFS going out, but I just got it replaced. Oh well...time to do some diagnostics.

 

Giac flash on what kind of set up? I used to have Giac flash two years ago. Stage IV EVOMS and SG700. ABS/PSM is definately MAF issue. Are you also running external WG's?

 

In addition to GIAC I have Gemballa exhaust.

Besides the upgraded DVs, the rest is stock (K16), no external WGs. Kind of strange that MAFS would go out again...I just had it replaced...stock air box with a new filter.

 

DV's need to be re-checked, it could be a cause. MAF problems usually start at 600HP or more but does not rule out things. Make sure you buy the new MAF and replace it. I've heard shops put in used ones or they take yours that is good and put another bad one so you go back and purchase another one. Believe me it sounds sick but it's happened to me

 

You can also try to unplug the MAF and take a drive,when car runs perfect without the Maf,than the MAF is the problem.
My car used to go in limpmode and the problem was bad Forge diverter valves,
replaced them with the upgraded Bosch ones and never had a limp mode again.

 

you can clean the maf... also put back the original filter...

 

Thanks guys. I'll unplug it and give it a drive. If it looks to be the MAFS I'll give it a cleaning.

 

is the new filter an oiled type? if so try the plain paper one, that solived the pro for me some years ago

 

use elec cleaner u can get it a ace hardwear cost under $5.00 as i rember... good luck

 

Thanks man. The filter is OEM so it's not oiled. The old filter was the same type, just really dirty so I thought that could have fouled up the previous MAFS, but I don't understand why the "new" one would have went after I changed the filter. I put 5 miles on it (after new filter) before I got the errors again.

I've used carb cleaner on another MAFS that went back some years ago and that did the trick. Is carb cleaner okay for P-car MAFS?

BTW - I really like your Turbo. White is my favorite color. I used to have a 996C2 in White.

 

NO! You want a cleaner that has absolutely no residual. Carb cleaners can have some compounds that do not fully evaporate.

Indeed it is this kind of stuff (diesel exhaust, particulates, etc) that contaminates MAFs to begin with- not all at once, but small amounts over time. Oiled filters do it quickly, and "hi flow" filters just let more crap in...

 

This is what I would do to rule out the MAF. Start the car and let it idle. Then while it's idling, go disconnect the MAF. If you notice an change in the idle then chances are your MAF is fine. If the idle stays the same your MAF is most likely bad. That usually helps narrow down the issue.