Strange cut off's

Since I have my 98 Impreza Sport Wagon Turbo (October 2005) I have sometimes cut-offs.
They never happen when the engine is not on normal temperature. As soon as the engine is on normal operation temperature and you push the throttle full down it cuts off round about 3000-3500 RPMs.
The boost differs between 0.9 and 1.1 bar when the cut-off happen. (Feels like you turn the ignition off during take-off)

The cut-offs are not always there, just sometimes.
E.G.: This afternoon I tried to get these cut offs, but I could do what I want, they didn't happen. Tonight on my way back home they where back again.

I thought first, it is an overboost but then I brought my car to Subaru (HP Dennis in Dublin) and they put it on the diag.
They said it is miss fire and I should change the sparks. I did it, but the problem still came up.
Then I brought it back to HP Dennis again and they thought it might be the MAS and I changed that part as well. Still the problem came up. That was before I modified the engine.

In the meantime I have chipped and remapped the car and the problem is still there. I was over in Germany in April for 2 weeks and there it never happened. Since I was back here in Ireland, the problem appeared again. I can do what I want, I used 95 Octane or 100 Octane petrol (you know the good stuff from Shell) no difference.

I have a Superchips chiptunig, increased the boost to 1.3 bar, an K&N intake kit, Baileys Dumpvalve, stainless decat centerpart with a Ninja backbox.

The car is remapped and I have tried almost everything and removed the boost controller against a manual one (fixed to max 1.3 bar).

I am runnig out of ideas. Maybe somenone here has a hint what else I could try?

Please help, I am beginning to lose my mind about htis strange behavior of my Scooby.

Regards

Axel

somethin like that was happenin to mine a while back and it was the air flow sensor gone. i broke it while changin the spark plugs maybe worth a look :dunno: hope this is some help


cally

[quote author=cally link=topic=2520.msg23167#msg23167 date=1180973088]
somethin like that was happenin to mine a while back and it was the air flow sensor gone. i broke it while changin the spark plugs maybe worth a look :dunno: hope this is some help


cally
[/quote]

Thanks Cally,

but that was the second thing (MAS) I swapped and guess what... Didn't help.

:cheers:

Axel :guinness:

hi akki, id say it could be something loose ,maybe coilpack or somewhere in the transmission,its a weird one as it only happens the odd time,just check all the connections and make sure there clean,if anything was faulty it should happen all the time,i could be wrong.

another thing is you said your car is remapped,is that for are 95 octane feul?you aslo said you used 100 octane feul and it made no difference,did you get this fuel in germany as you can only get 95 in ireland,shells v-power is only 95 in ireland

[quote author=johnny5 link=topic=2520.msg23182#msg23182 date=1180992916]
hi akki, id say it could be something loose ,maybe coilpack or somewhere in the transmission,its a weird one as it only happens the odd time,just check all the connections and make sure there clean,if anything was faulty it should happen all the time,i could be wrong.

another thing is you said your car is remapped,is that for are 95 octane feul?you aslo said you used 100 octane feul and it made no difference,did you get this fuel in germany as you can only get 95 in ireland,shells v-power is only 95 in ireland
[/quote]

Hi Johnny,

I got the gearbox replaced just last Tuesday. I could not see any problems with the connectors. Seems to be fine.

Regarding the remapping there could be something on it. In Germany I only used 100 Octane. I thought the Shell V-Power here would have 100 Octane as well.
I wasn't aware that they only have 95 Octane

The chipping and re-mapping was done here in Dublin with a Superchips dealer. I am not sure if has mapped for 95 Octane.
I think I have to research that.

Maybe you know them (Mc Namaras Carburation and Injection Center)?

I have already invested hundreds of Euros for garage and spareparts etc. and HP Dennis will not take the MAFS back. They even wasn't able to find any problem. The error memory was completely clean apart from the miss-fire. But this was gone after I have changed the spark plugs.

Maybe here in the club you know someone competent who is able to check my mappings?

Thanks for your help anyway and lets go for a pint some time.

Axel

I had a car(starlet turbo) superchipped from the same lad's and mapped.
They never mapped the car just put the chip in but charged me for the map.
Car ran crap got them to take it out and got me money back they dont have a clue.
I would get someone who know's what they are doing to have a look at it.
Have heard some bad things about superchip's and impreza's :dunno:

Hello Akki,

I think you should talk to Damo (reno555) about this fault, I have not heard of anyone fitting a superchip to their car on the site todate. Most people who have a remap done have either had the ecu replaced and the new one programed once fitted or their existing ecu reprogramed.

As Johnny5 said there is no 100Ron fuel available in Ireland, this might be part of your problem that you car is not set up correctly fuel wise 

Cheers,

Michael

Thanks guys,

to be honest I had the suspission already when I got my car back last year.
I overboosted my Scooby to 1.3 bar via a manual boost controller.
When I got her back I couldn't feel any change in thrust nor response.

I went back and complained. He told me that they only had changed the boost and fuel mappings to match it to my boost settings and everything is OK.
He said since I have that milage he woulkd not do more or my engine could blow up. That sounded logically first.

Now I have seen your comments and I removed my manual boost controller and re-inserted the original one. Guess what... Boost is max 0.7 bar.

I am really pi**ed off now. 

Tomorrow first thing I go back to their shop in they have to fix that. Next thing I will complain to Superchips UK about them.
I never expected that the only Superchips dealer in Ireland would do such a scam.  :hang:

Further they have to show me the mappings and I will have a copy of it. Then I will send it over to Superchips UK for analyzis.

I heard only good things about Superchips, but mainly in UK. Never met one who has it done here till now.

This is redicules..... :shoot:

Axel

[quote author=Michael Spec C link=topic=2520.msg23264#msg23264 date=1181065834]
Hello Akki,

I think you should talk to Damo (reno555) about this fault, I have not heard of anyone fitting a superchip to their car on the site todate. Most people who have a remap done have either had the ecu replaced and the new one programed once fitted or their existing ecu reprogramed.

As Johnny5 said there is no 100Ron fuel available in Ireland, this might be part of your problem that you car is not set up correctly fuel wise

Cheers,

Michael
[/quote]

Sorry to bother agin... What about the Shell V-Power. They sell it as 100 Octane fuel... Or am I missunderstanding something.
And why is it 5 cent more expensive?

Axel

V power is 95 not worth the money

hi akki again,the v-power thing,its only really to help clean your engine out and it also doesnt agree with octane boosters if your using any,lots of the lads here us lucas octane booster including myself and it seems to work well,but gives out a lot of deth when used with shell v-power or texcos tectone,you should stick to esso or shell 95 with a booster or go back and get your money back of mac namaras and then get a remap for your mods off andy forrest,hes probably the best anywhere in the world out side of japan

Re: Strange cut off's (Update)

Finally my issue seems to be solved.
I was in MacNamaras today for about 3 hours and the folks there did a lot of testing and analyzing.
I can not say, that they have no clue, rather they know their job.

Here is a little info about the superchip and how it works:
The Superchips is not a re-map for you car. The superchip is an extended box with a computer chip in it and an eprom where they can match the fuel ammount to the turbo boost setting.
Since I have overboosted my Scooby to 1.3 bar, there was a need to enrich the fuel ammount provided to the engine. Means more boost = more fuel.
More boost basically means that the ammount of air pushed into the piston from the turbo charger is much higher as higher you set the pressure. Therefor the chip is only used to do that.
Further the chip rises the over-boost protection setting. Thats basically all. The 98 Subaru Impreza has the fuel mappings and boost settings hardwired into the ECU CPU and they can not be modified nor can you use a piggy-back ECU upgrade as it was possible with the 92-96 Scooby's.

If I want to change my mappings, I have to get a complete different ECU (like APEX etc.) and that is not cheap.

Long story short end... They have done 4 test drives, could reproduce the issue, have checked the ECU error log, checked all sensors and valves (they are all fine), have checked the oxygen sensor and checked the emission values (all tip-top).

Since technically my scooby is in best form, there was only one thing which could cause the problem.... 95ROZ crap-fuel.
I got a can Wynns Octan Boost for free to see if it works. And it does. Further they didn't charged me a penny today. They said this is customer service

I tested my Scooby the whole afternoon, did several different driving styles but the problem seems to be gone.
I will see tomorrow if that really works for now. But I could reproduce the problem over the last couple of days easily as we could do this morning. But since I have the octane boost stuff in my tank, the baby runs like it should.

Anyway... I have to say thank you to all you nice people for all your help, hints and tips.

I ordered today a box of Lucas Octane Boost from Streetperformance. On the weekend I will take my Scooby for a nice long spin.

Thanks again  :worship: and hopefully we see us some stage.

Cheers :cheers:

Axel

It's great when it all works out in the end