Hi,

Not sure I quite get what you mean by 1/2 a tooth out madscoob...unless you mean half a tooths width of slack that's taken up by the tentioner, effectively turning that cam slightly out of alignment - that would make sense. I.e cam is lined up perfectly, tensioner is..well, tentioned causing that one cam to rotate by a couple of degrees while the others do not - purely due to it's proximity to the tensioner and all slack being taken from there. That what you mean? Hadn't really thought that could happen if everything was lined up properly - but then I've never changed a cam belt on any car myself.

Additionally we think that just one cylinder is causing the issue and, with four cams of course, it would all fit one possibly being out.

I guess I'll just have to wait for Len to confirm this prior to doing the injector change. On the slight chance it IS out slightly on just one, then it would explain things potentially.

G.

 

I feel for you, been somewhere there... Hope you sort it soon!

In my case, which sounds quite similar, after replacing lot of parts and dismantling half of the engine, replacing the injectors solved the issue! This just highlights the importance of the flow(and pattern) of the injector.
In respect to timing, it was down and detonating, and started doing it for no apparent reason and no changes to the car... so first I had a safe map, then after quite a few trials, the injector replacement solved the issue.

Since then I invested in a tactrix cable, and I read the ecu to check if all is ok. This was few years back, and since then it helped me detect issues and correct them, so I highly recommend this

 

I had a couple of cars with similar issues. One car the up-pipe was fractured internally with the only clue being occasional fumes. Once the pipe was removed it fell apart. Replaced with a Harvey up-pipe with solid results. This car was circa 30bhp down on power.
A second car had an exhaust blockage. We simply removed the back box and ran the car without it to test. This car ran much better and a replacement box left it healthy again. This car struggled with boost.
Worth a check as we fought with both cars over several days before getting a result.
A cracked wastegate housing is something also worth checking if you were running lean.

 

Hi,

Very interesting posts maci and scubbay, thanks for those. I'm still waiting to hear from Len, but it sounds like Injectors are indeed a real candidate based on your experience maci. Also, I think it's of value to check the exhaust system more carefully once more as your problem shows scubbay.

Sorta playing a waiting game now while we coordinate the injectors being ready, Simons next visit to Subaru4You and my own free time!

I will post back here as things progress.

Cheers,

G.

 

You have said that it is well serviced but as not been run much. Due to my work I am used to working with diesel generators that even though well serviced by hours run. The time taken for these hours to add up takes a while. When we did max generator load checks, like a RR on a car if they did not make the top 10% we would do a de-coke run and a de-glassing run to no effect. After a bit of rational thinking I opted to replace the fuel filters (500 hours early) once fitted all was good. The filters had collapsed and were restricting fuel flow at the top end. So in your case this running lean would cause your knock and require simon to pull back the timing. Hope my experiences help you out.

 

Hi 360ste,

Good points there and I did consider that time spent parked up might be a factor in the cars poor running. That's largely why I wanted to ensure the large service it was due was completed before we started another session of RR. Unfortunately it didn't help, despite new fuel filters and a cleaned air filter etc.

It does concern me overall that sometimes the car doesn't get run for weeks, simply due to lack of time & other things going on. Especially lately when it's been off the road between visits to Len's to try to get things sorted.

Still hoping the injectors will do the trick, but we have a few other things to double-check based on peoples postings here.

G.

 

Hi all,

An update.

Was at Subaru4you today - had the fully tested 440 injectors fitted replacing my own and the car immediately idled better. It also sounded different, smoother and quieter. A good sign.

Car was dyno'd and the map tweaked by Simon and managed 280bhp/280ft.lbs peak with a nice sharp boost curve, torque building quickly before maxing at a little over 3,500rpm and holding until 5,500rpm before starting to slowly drop off.

So, power still isn't quite where I'd hoped but the little quirks have gone and the car feels really smooth once more.

Speaking to Simon he thinks (it being a hot day and all) that my top-mount and standard induction are now more of a limiting factor. However some cars with similar mods do make more on the same bits. Still, I'm happy that the issue has finally been identified and fixed and is what I suspected. Old injectors are being sent off to be checked, but more out of interest than anything - plus Len can then sell them on once fixed as I had the ones he fitted as part-ex in effect.

Ironically, I've been holding off on other mods for quite some time as I wanted to ensure my car was running absolutely spot-on before I started changing things...the first things I planned to change were Turbo (I bought a new actuator for this one to fix a problem), new larger injectors (just fitted flow tested ones) along with a front mount, map (I've paid for a few dyno runs lately!) So, in perfect 20/20 hindsight, if I'd just gone with my mods I've have "fixed" the problem that way lol.

Think I will now just concentrate on actually driving the car for a bit before I do anything else - give time for my "car pot" to recover a little too.

Cheers,

G.