"help Me" Fuel Cut When Wrx Turbo Spools

Hey,
i'm having a serious problem with my car and I'm still finding the actual source of the problem.
I drive a 2002 wrx with a stage 2 reflash with a full turbo back and equal length headers.
The problem is that there is an immediete fuel cut when the turbo spools or when the turbo pressure meter goes above zero psi. I can reach 70 miles per hour but at a very slow pace because I can't kick in my turbo. When I try to spool the turbo, the vehicle immedietly seems to slow down.
This happened yesterday and it was a highway struggle on my way home.
I can still run the car as I have to manage the wrx RPMS so that it doesn't actually activate the turbo.
There is a out of the ordinary whining sound when I start my vehicle near the rear tires.
My friend Pheng who drives an STI assumed that my fuel pump is dying.
My friend Fong who drives a forrester XT recommended me to check all the air lines or the turbo intakes for any leaks. So far, no leaks and its been checked already.
My other friend Lou who drives an RS said that it might be because of bad gas and that I should burn off all the gas and repump octane 92.
Could it be the MAF sensor that measures and balances the air fuel ratio.
The oil light or engine light doesnt come on at all during driving.
Whenever I step on the gas hard to bring in turbo pressure for the car, the car immedietly decellerates and fuel is cut, whats funny is that I have to switch gears to RESET this and the car starts working again.
It ran fine yesterday morning until after 4 pm, tank was at 3/4 full, I ran up to 2nd gear and pushed it to 4000 rpm and then I had immediete fuel cut, i thought my clutch was slipping and it wasnt.
Right now it's running the SUPER AMERICA gas.

Any reasonable explanation would help so much.

thanks, mnsubaru!

 

I think you have a nasty hole in your fuel mag

 

i bet your EGT sensor is funked

 

Fuel pressure regulator?

 

thanks for the early quick response, I'll take your advices into consideration.

if my car survives the day,
i'll bring it up to Firestone at Midway.
thanks guys

 

Change your oil lately??? Low oil pressure or old used watery oil causing spuddering of oil over valvetrain or sensor. Car may be reading that its not up to optimal performing conditions hence trying to save itself from exploding but means of fuel cutting. This is known in the world of other makers such as Honda AKA LIMP MODE!!! keep us up to date on what this is. I wonder if subaru has limp mode? anybody?

 

Subaru only has a default mode when it has a check engine light.

 

Quick update on my way to work

It can't rev past 3000 RPM.
whenever I press hard on the gas paddle on any gear, i can't pass 3000 RPM.
immediete decceleration at 3000 rpm.
runs fine below 3000 rpm.

 

Bbsrs

 

Subaru's do have a limp mode (actually, a couple variety's), one of which will disable boost control if the car is knocking very badly.

However, he'd probably still be able to get up to WG pressure if that was the case.

 

Car Is blacking Out Under Boost!!!!

 

Maybe this will help, I recently had an issue I just had with my 02 WRX that might be along the same lines. My car would idol fine. I could drive it ok, when I would try to "gun it" or drop gears on the freeway or just try to speed up some, it would seem to lose power/slow down/just sort of die/choke out on me. When I took it in, the found that my Ignition Coil was Faulty, hence the losing power/shutting down a lil. Quick fix, they ordered a new one, 20 minutes to replace, and $150 later my car is fine.

 

Multitude of possible issues:
Fuel delivery
Ignition
Tune
Mechanical problem such as boost leak, MAS, turbocharger.

I would recommend bringing it somewhere for DIAG versus just throwing parts at it.

 

Ohhhhh you're too funny:biggrin:

 

Sounds to me thats its alot like the honda's except that they choke, bog, fuel cut, rev limited, etc..etc..etc.. at 4000 rpms. Could be anything along the lines of what LSE mentioned in the posts above. A buddy of mine had the same problem in his honda and brought to my attention. After a few days of checking the car over it came down to the fact that he hasn't change his oil in a while and so it was old and water like and very low. This caused the oil to splutter over the valve train and not lube as well, and seeing that it was a honda with vtec not a subaru with turbo right when the vtec was about to kick in BOGG, fuel cut what ever you get the idea. by the way you still haven't mention when you last change your oil? It could be that simple!!! if i remember right your car should take 5 quarts + alittle maybe even. I know my N/A takes alittle over 4, about 4.6 quarts or so to be full accorking to my oil dip stick in my car. I don't know about others though so people don't come after me about how much oil goes into my car. Mine just takes that much to be happy. =)

looks like frichdan had the same problem as well. That would be a very good start i would think. It'll all come down to maintainance and check ups wheather you do it (trial and error) or pay the shops to.

 

hey, the last time i got an oil change for the vehicle was when my friend had it, i think he changed it around spring. the 2nd mile guage reads 2800 miles running on synthetic oil. im going to go ahead and get an oil chang for it asap when i get off work. i sure hope that fixes the problem. will keep you guys updated. but hey, you guys rock and thanks for the help. this is my first subaru.

 

I agree on the Oil Change. Its been about 7-8K miles on my 02WRx since I havn't do my oil change. I do notice a lot in performance of the car. It feels like the cars powerband is so ROUGHT, doesn't have that smooth reving feeling like when the oils are new. Need to do oil change this weekend.

 

omg, now the cars blacking out too......hehehe..


ohh we just love having you around Nate.............................

 

Oil Change is complete but still having major issues

After work, i did an oil change,
stuck in some Mobile 1 5w30 fully synthetic into the vehicle and changed out the oil filter.
Lightly ran the car around the block to filter in the new oil through the engine.
then I started to rev it up.

Same problem still persists.
To take it towards a deeper thought, i guess it isn't RPM limited. Everytime I press hard on the gas, fuel is immedietly cut off. I have to press very lightly on the gas to get the vehicle to run.
here is the RPM max on each gear.
1ST GEAR 4K RPM UNDER ZERO PSI
2ND GEAR 3K RPM UNDER ZERO PSI
3RD GEAR 3K RPM UNDER ZERO PSI
4TH GEAR 3K RPM UNDER ZERO PSI
5TH GEAR 3K RPM UNDER ZERO PSI

Has a struggle from 45 mph towards highway speed of 60mph.

Could it be the fuel pump??
when I start up my car, it makes a recognizable whining sound, "fuel pump possibly" then it fades away in 2 minutes.

When I press hard on the fuel paddle, it bogs down or decellerates. I have to lightly press on the gas to accelerate.

Any ideas, clues, suggestions please.
thanks

 

why am I not surprised... never have I heard of that problem with the oil!!

the fuel pump usually makes some noise but if it is making noise till 2 minutes or so then maybe it is on its way out.. but is that the cause... slightly doubtful....

if it is doing stuff when you are applying or having to un-apply then I would maybe think it could be the TPS playing games?? but that is a guess...

as someone has stated... save yourself money in the long run by not blowing up your engine by driving it hard trying to figure out things and just pony up and get it looked at by a GOOD shop....

 

My friend Fuji_K is on vacation fishing, I have to wait until Monday until he gets back so i can do a full diagnostics and inspection in his garage.

I guess your right, i should be careful not try to blow up my engine.
I kinda hope that some new octane 92 would fix the problem for my wrx.

 

Again,
Fuel delivery
Ignition
Tune (metering issue)
Induction system
Your problem lyes in those systems.

 

this is exactly what happend to a trade in that was totally beat up and was missing the EGT, any codes?

 

He said there is no CEL. Is there a aftermarket intake on the car?

 

it's your spark plugs, change them and call it a day! actually, i'm at home now from fishing come over if you want me to look at it or call me.

 

closest would be coilpack probably.

The car DOES NOT have an exhaust note when it bogs down. A/F meter reads LEAN when it's bogging and engine RPMs slowly dropping w/ throttle position 75%-100%. Engine can REV with 1-10% throttle but cuts at 4k-rpms. Engine cuts more if more throttle is applied.

 

cam sensor?

 

Oh yeah,
forgot to mention that the maf sensor connection was removed and tested.
Interesting how the vehicle reacted the same way in safe mode with the maf sensor removed.
Cuts fuel at 2500 rpm.
Plugged the maf sensor back on and things were still messed up with my wrx.

 

I was desperately looking around and stumbled across to this product.
Will this fix myproblem.
http://www.scoobytuner.com/products/?vApplicationID=17&sfID1=4&productID=902

 

Does anybody know any links for a coil pack or is the coil pack also known as the ignition coil.


I sure hope I can get my vehicle running well after I reinstall new spark plugs otherwise I might end up with a few hundred dollars of 2002 wrx spare parts.

 

hmmm... vacuum line leak? TPS sensor? Does it idle fine?

 

it idles fine, no abrupt jumping RPM meter.
but when I gas it at neutral, it bogs down or fuel cuts at 4000 RPM.

 

Coil pack = Ignition coil

 

I don't know for sure but check your vacuum lines.

Did this start out of nowhere? Can you think of anything that you did to the car just prior to the problem starting?

 

i'd slit your wrist for you if I saw you with that. :biggrin:

 

if you are gonna throw $110 at something that you have NO idea if it will even solve your problem spend the same damn money and get it inspected by someone who can help work it out...

 

No, this will not fix the core problem.

 

Once again, does it have an aftermarket intake?

 

What mods are on this thing, if any?

 

That wasn't very clear in his post. Sounds like it's more load effected than RPM effected. If it were a coil, it would more than likely still rev, but rev very slowly under any load.

Sounds to me like you may have a bad front oxygen sensor, but then again...your car idles fine.

 

I agree! A lot of people up here have good ideas... But, you obviously don't know enough about the car to fix it yourself... no offense, hell, I don't know enough about my car, so I tend to take it in a bunch! But that saves me time. Just pay the $110-150 to have someone who knows what they are doing take a look at it! Unless you like not knowing what it is for sure and like guessing at the issue for weeks!

Just take it in!

 

No, lets just keep throwing parts at.