Ok been reading a lot of posts on here and still can't find a resolution to my problem so I'm going to attempt to be more detailed about the fault and just hope someone with a similar problem in the past recognises the symptoms.

It's a 1996 uk turbo 2000, has an updated td05 turbo and front mount intercooler along with 3.5" straight through exhaust and decat.

Boost will not rise above 0.4 so I have checked and changed the following:

Boost solenoid - replaced
Maff - replaced
Vacuum lines - replaced
Wastegate - tested ok
Dump valve - tested ok
Lambda sensor - possibly faulty - new one on its way
Boost pill - wasn't fitted but is now

Took it to subaruforyou in Newbury but they were unable to test and do anything as they would prefer it was mapped first - yes totally agree but before I spend another grand I wanna resolve this issue first to avoid another large bill.

I'm no expert and am really scratching my head, I'm not 100% sure about testing a wastegate but I removed the vacuum line and took it easy for a bit around the block and noticed no apparent change.

Subaruforyou has confirmed all pipe work is correctly routed and going where it should so any ideas ?

The rest of the car is spot on hence why I'm putting in all effort to try and get this all sorted, so is this a case of a possibly knackered turbo ?

The lambda sensor did flag up a fault code so I have ordered a new one which I will fit the minute it gets here but if this was at fault would it cause this issue with the power ? If yes can I unplug it so it runs a little richer to see if performance improves ?

Any ideas in general will be tried before I go completely insane

 

Get it in to a reputable tuner with a rolling road. Then a full diagnostic can be done otherwise you will be replacing parts that are not broken.

 

Problem is I've tried that and because it's running lean due to its mods they won't run it on a dyno and do any fault finding in fear of knackering the engine so as I see it I have no other option but test everything separately.

 

intercooler hoses all tight? is the turbo a genuine?

 

Yeah all hoses were checked and took ages to do all of them lol, the turbo as far as I can tell after stripping it down looks good with no play in it and the fins are in good shape. Also checked oil is passing through ok and then carried out an oil change anyway with top quality oil and filter.

 

You don't have to spend anywhere near a grand to get it mapped.

 

Yeah sorry that price was for an ecu and dyno too

 

wastegate stuck open?

 

Check that the waste gate is still attached to the actuator, Maybe the little cir clip has come off and now waste gate flap is stuck open?!
Blow of valve leaking?!

 

New turbo,fmic and decat.
The lack of remap is the issue.

 

^^^this^^^

 

So if I have the ecu done and remapped this will fix all my problems and there isn't anything else that can be causing the issues I'm having ?

Waste gate is all fine and checked in full, I have got a spare couple of turbos so could swap it over just to be sure and to rule out any fault with the existing one.

 

Not necessarily but it will give you chance to have a proper diagnostic in a safe environment, subaru 4 u come highly recommended so you'll be in safe hands and at a place where they can help solve any issues on the day, i'd use JGM as he seems to do a lot there.

Otherwise your just going to continue swapping parts to no avail, and if/ when you find the problem you'll still need a mapping session to sort out the lean running, so just bite the bullet and have it mapped, better than driving around with a lean running engine.

 

Yea as above, mapping might be expensive but throwing parts at it isn't cheap either. Is your exhaust really 3.5" bore?

 

Is it running in safe mode because of the mods?

 

Good question mate and one I'm not sure of ?

I did reset the ecu and took it out again once I checked there were not faults registering which there isn't but still it won't boost properly or past 0.4 think I'm going to rip out the turbo too and refit my hybrid td04 that's now ready to go and see if that helps

 

Ok well swapped the turbo for another one that I know is spot on and still the same !!!

 

It sounds like its running wastegate spring pressure, if you plug your wastegate actuator so that theres no way the ecu can control boost and it still doesnt boost properly then that rules out any of the cars electronic control systems and leaves you with a mechanical problem

 

this is a strange one bud. in my case i bought my boss,s 2002 bugeye sti and it felt pretty quick but had a hesitation and was only boosting to 0.5 bar so took it to RA motorsport my local specialist and straight away he noticed the boost pill was missing. to test this i did what you said you tried and took the vac pipes off actuator and the turbo nipple and had a quick drive round the corner and bam! it shot up to 1.5 bar on the defis! so i got a replacement for the pill and its pulling like it should. you should have seen a difference similar to mine when the vac pipes are off. as others have said it needs a map for all the changes especially turbo, fmic and decat which all affect air/fuelling. you would still expect to see a noticible difference when the pipes are off the turbo tho? time for a specialist bud as the money your spending on parts could go to paying for his time to fix properly. good luck with it.

 

I think you should get a decent mapper on it before it's too late.

 

Is the boost pill in the right place I remember we had a classic in at Subaru years ago same symptoms and the boost pill was in the wrong pipe I'm sure it was that.
Even with the turbo and cooler the car will still boost to what the ecu has programmed, it probably won't feel nice but it will want to give it to you if the ecu senses over boost it will fuel cut anyway and if it was in limp mode the light would be on.

Solution for me would be get it mapped and find the fault then get Duncan out he's about 350 and will more than likely sus the problem in minutes.

 

The right place as far as in aware is on the very bottom pipe coming off the boost solenoid going to the actuator itself approx 4-6" in from the solenoid within the actual pipe itself with a 2mm hole through the centre of it.

 

check the link i sent the pill should be on the other side at the compressor nipple before the tee piece

 

Thats the wrong place for the pill. It goes in the vac pipe from the turbo nipple to the T-piece

 

just to say thats for a 2 port, i believe its different for a 3 port?? maybe someone can pitch in who has a 3 port.

 

Mines a 3 port not a two port

 

3 port iirc is the bottom hose

 

Can anyone clearly show where each individual pipe from the boost solenoid goes please ?

I thought I had it sudden but other forums show that my top and bottom pipes may infact be back to front ?

Can someone please clear it up for definite ?

Thanks

 

If the problem has occured since changing turbo & intercooler then I would say its the front mount causing it and needs a remap,my friend put fmi on his 200sx without a map and it wouldn't boost up. Or possibly restrictor pill missing, Also if your still using original actuator on uprated turbo then maybe the spring is too week to hold the boost and needs uprating! I actually changed my actuator once just because I had a spare that was bigger with stiffer spring and car run like a pile if s**t and wouldn't boost.I had set actuator rod up incorrectly and wastegate wasn't closed all the way home, even though I had fiddled with it for ages and was sure I had it right

 

Ok after many hours of trying I'm going to have to give up, I've tried every idea going but it's just not boosting it's as though it's a non turbo car. Going to start putting some money away and will get an ecu and remap and just keep my fingers crossed that this is all a result if something ecu related.