Hercules

Hi all,

Car has slowly got worse and worse now it won't rev past 2k.......sometimes it will but then will bog down and misfire but most of the time its as if i'm hitting a limiter. Its not limp home mode as I have had that before.

Pulling codes didn't really reveal anything apart from DPF back pressure being to high, ok well the dpf is on its way out so unbolted the DPF and the engine behaves exactly the same. I will flash with dpf delete when I have time but I thought if the DPF was causing excessive backpressure I would see some benefit from temporarily removing it, but no.

Can't hear any whines from the fuel pumps, so i'm thinking a dodgy turbo now its done 140k hard miles. How can I check the turbo easily, take the induction pipes off and see if the actuator ring moves properly?

I am in the process of setting up DIS to maybe do some more in depth diagnosis as im only using INPA at the moment. Is there anything within DIS that could help me diagnose? anybody had similar symptoms?

My 3rd daughter born by section tomorrow so could do with sorting this out! it never rains it pours!

Thanks guys

Steve

Redtwin

Try disconnecting MAF and see if there is any improvement.

Turbo actuator or could also be the culprit even if the turbo itself appears OK mechanically.I think your car used the vacuum controlled actuator in which case also check for perished vacuum pipes.

bobbyggx

The DPF is your problem. When you unbolted it the pressure dropped and you got again an error which most probably wast stating "Low pressure". Clean the DPF or remove it and you should be up and running.

Hercules

thanks for the reply guys forgot to say tried maf already that didn't make any difference.
Im pretty sure its vvt/vnt turbo on mine so will it still be vacuum controlled?
bobby, im sure it would be throwing a low back pressure after i removed the dpf but surely that would have been putting in me limp home mode at worst? The car seems a lot less responsive than lhm....

bobbyggx

Well the computer cuts your fuel in order to preserve the engine of failing. I had similar problems and removing the DPF was the resolution of them. After I removed the DPF and before uploading the new software with disabled DPF the car was getting the low pressure fault and it didn't ran okay. After the upload everything went back to normal.

When the computer cuts your fuel it always writes you an error message, because this is a handled exception and you can tell what the problem is by reading the fault codes - so go ahead and either clean or remove the DPF and enjoy your car

Hercules

Ok Bobby, I wanted to avoid flashing the DPF removal in case that compounded my problem but I might as well give it a go.....

Hercules

Oh by the way Ella was born 6 lbs 5 1/2 Oz's both mother and baby are doing well!

bobbyggx

From your posts I understand that you have the hardware to reflash the ECU, so just make a backup copy the original one and afterwards go ahead and reflash it with the DPF removal and see if it will be OK with the unscrewed DPF, but I'm guessing it will be.

P.S. Happy for you and your family which is bigger now I wish you only joy from now on with the little precious.

Hercules

Well my daughter is 15 months old........and my beamer still out of action! lol I tried removing the DPF and flashing the dpf out but same story........


When I was doing some testing the pipe connected to the EGR stat blew out.....so that needs replacing but the stat shouldn't have been causing the problems......but will get that replaced.....


so things I think it may be:
Faulty turbo
Blocked cat
Some kind of coking inside the heads (coke head :-) )


really starting to depress me now and as much as I love my Impreza turbo its not really that good with MPG! any ideas what could be stopping the car revving past 2k?


I have had DIS running its pulling no faults, I have run through a few test scenarios but nothing jumps out at me......

jtbgonesailing

First thoughts you hit on... Restriction in exhaust/particle filter or turbo not spooling up.