Splitpin

Furry muff, can only be mix-up in Subaru's parts numbering system then. Let us know whether the other number turns out to be the correct one. Oh - and boost gauge, sort it!

dan83590

Just a thought. If you were worried about damaging a standard interior with the addition of a boost gauge you could always just set it up temporarily. They are handy to have for any turbocharged vehicle be it petrol or diesel.

prodrive.greeny

iTrader: (3)

Boost guage if i ever set one up it will be a temp fixture - but still i'm going to have to slice one of the pipes to make way for a t-piece. Not a massive fan, but clearly when nature calls..

Splitpin

You shouldn't have to cut anything. On a 99-00 there should be a spare takeoff on the front of the inlet manifold with a bung on it.

If you don't want to get involved with that the other (in many ways better) option is to get yourself a diagnostic interface and use a laptop.

ZEN Performance

This all looks like a long protracted PITA that could have been sorted out long ago, and as of right now, nobody knows 100% what the problem actually is.

Stop fannying around and get the thing looked at by someone that knows what they're doing (this may not be the same thing as someone that just says they know what they're doing!).

prodrive.greeny

iTrader: (3)

Well rigged up a boost guage earlier running it off the blanked take-off on the manifold. Ran the pipe from there out from the bonnet through the intercooler scoop and then through the passenger window into my mates lap - yeh i know, pretty cool

So proceeded to take her for a blast up a nearby clear bit of road (up hill). Befoer you read on i better note that sods law the car didn't misbehave one bit on this test run which is so typical of problems like this. But anyhoo, results were as follows:

Idle = circa -0.8 bar
Boost holding at around 0.8 bar
Boost peaking at around 0.9 bar (never went past 1.0 bar)

My mate (mechanic) noted how healthy the turbo seemed but i thought the Prodrive ECU's were meant to peak at around 1.1bar?? Which means i'm under boosting which is doubley wierd as the boost on mine feels pretty potant.

Also at idle the guage wasn't solid, ie it was fluttery. I guessed this was normal due to the nature of the engine as when you applied some revs the fluttering went?? But could also mean a leak somewhere right?

Splitpin

Reiterating what Paul, myself and others have already said, some expert advice here would probably not go amiss if you want this licked, but the boost gauge is a step forward.

A couple of observations: Hot idle vacuum should be nearer the -0.63-0.68 bar area. Hearing that it is idling at -0.8 or so is highly unusual. This leads one to wonder how accurate your gauge is - and there's a clear inference too that if it's the regular unpowered mechanical sort, if it reads too much vacuum, it'll under-read under boost too. If we added 0.15 bar to all the readings that'd give you 0.95 bar held boost and peaks of 1.05, which would be bang in the ballpark.

It's also potentially significant to hear you say that the car resolutely refused to misbehave today. Today has been quite a warm day - with correspondingly high ambient air temps. Can you make any links between the severity of your problem and air temperature? Does your missing/hesitation problem get worse on very cold days, for example? UK classic Imprezas don't have any form of inlet air temperature compensation, which means they generate less boost on a hot day than on a cold one. Conversely, the colder the air temp, the more boost you'll get - and the more pronounced any overboost wil be.

If you have the ability to do so via the shop, or if your mate can, I would try and check that gauge against a known accurate pressure source. Or try another one and see if it reads significantly different. I suspect you'll find it ain't that accurate. Shouldn't "flutter" too much either.

Oh - incidentally, are all your boost pipes clean now?

Scooby715

0.9 sounds a bit low to me too fella, i thought ppp's ran between 1.1-1.2 bar?? just a thought but any chance a manual boost controller has been fitted in-line somewhere?? It would explain a few things i.e why the std boost controller isn't cutting in cos you've said it 'jerks' through the rev range, which sounds like fuel cut to me NOT boost control - the std boost controller backs off the boost gently then re-apply's it when its safe to do so but does so smoothly.

If an MBC has been fitted (again - its only a theory) then it may have been backed off to try and cover up the prob's your experiencing.

Also have you plugged the black ecu codes in again since? Might be worth checking no other sensor problems have surfaced too?

Only way your gonna move forward on this is to see the boost readings when its playing up imho...

Bob Rawle

A few notes that may help,

Plugs, what type, what are they gapped to and how old, boost cut would be smacking your head into the windscreen.

1.2 pill is correct for the PPP.

Its common to see a code 23 and it doesn't mean the maf is fubarred, the Jecs seems to like storing for no good reason.

I will check the PPP mapped boost when I can fire the laptop up tomorrow, I have the rom file, std boost is 0,95 bar.

Boost gauge readings on vacuum do not normally carry through if in error to positive boost, it does depend on the gauge though.

So suggest plugs out and check condition, close gaps to 0.65mm then test again, if more than 10k miles old replace with NGK PFR 7B ... www.sparkplugs.co.uk.

Boost cut is around 1.2 bar on the std ecu

cheers

bob

prodrive.greeny

iTrader: (3)

Thanks for all the input again guys.

Splitpin, like you say the guage was obviously reading slightly skew and imo the readings (if i had a more accurate guage and setup) would have been spot on. The guage was made by a company called 'Turbo Tim' iirc so wouldnt be surprised if it was dodgey

RE the weather, it was cooler down here today and i'm thinking it does get better in cooler temps as the last time i took it out and remember the problem seemingly dissapearing was when it was raining (rarely ever take it out in wet).

What my mate did point out was whether the fuel filter had been changed, and i'm pretty sure when i serviced it last i ignored this. So i'll stick her up on the ramps tomo and fit a new one and hope for the best. Where is the fuel filter located btw - is it in the bay or under the sill? He also did say the coilpacks or HT leads would be another thing to check - checking the leads by wrapping them in electrical tape one by one to test.

Scooby RE your point about the MBC - there's no visible controller anywhere amongst the turbo pipework so i can rule that out as a problem.

And Bob the plugs i used were NGK platinums and i didnt play with the gapping as they're set to 0.8mm out the factory which i've heard is pretty much bang on for the scoobs (correct me if i'm wrong).

Oooh, and yes splitpin all pipes and solenoid are uber clean now.

Splitpin

If it's a cheap nasty spring gauge, I wouldn't be at all surprised but as Bob says you can't take anything for granted. As a matter of interest, where does the gauge needle point to when disconnected from the car (or engine off)? Spot on 0, or...?

If "the problem" becomes less noticeable when temperatures are cooler, that suggests it isn't overboost. Your car is nothing if not full of contra-indications.

No need for ramps, the filter is in the engine bay bolted to the top of the nearside suspension turret. Easy peasy to change unless the fuel pipes are stuck firm to the tails of the old one.

Correct me if memory's getting hazy but isn't your problem an intermittent hesitation? If so you probably won't learn much by pulling/insulating them one by one.

0.65-0.7 is generally considered optimal

Question: We already know it behaved itself while you had mate + gauge installed, but have you actually had a recurrence of "the problem" since you put the pipes back together? If not I would be tempted to leave it as is for a few days just to see if it recurs. If not, go ahead and replace the filter and just keep a watching brief until/unless it recurs.

Oh - where do you normally leave the oil level? Does it go above the top hole when hot?

prodrive.greeny

iTrader: (3)

Right, Splitpin i'm not ignoring your post just found something pretty significant today in regards to the fuel filter.

As i work for a motorfactors i sourced the filter myself, typed in my reg on Mastercat and produced a choice of two filters under FRAM -G6827 and G7367. So ordered them both in and went to see which was the right one. (when out the box they both look near identical bar the way the pipes out the top are shaped, (see pic below)). Matched up the one that was already on the car to what i had in the boxes and G7367 was most similar so went to fit it. However when fitting the hoses seemed to have to stretch a bit too far so instantly thought the wrong filter had been previously fitted.

I called Subaru up and got the gen part number which brilliantly matched up with G6827 - not the one that was previously on the car

So removed G7367 and fitted G6827 (the correct one). I think i might have solved it as no misfires at all when i took it out for a quick spin, but then saying that there werent any y/day with the wrong filter fitted.

Anyway, i've attached some pictures for reference:

All 3 lined up, from left to right G6827 (the one i'm pointing at - correct one), then the old one in the middle and then G7367 (same as old one, so wrong).



New filter fitted



Oh and at my mates garage they were servicing this beast

Splitpin

TBH it's unlikely to be significant and most probably a red herring. I daresay that if you sliced those filters right down the middle you would find that, internally, they are identical, so from that point of view it wouldn't matter which type you fit. The only difference at the top is the routing of the inlet and outlet pipework.

Bottom line is this:



For what it's worth the two on the right are the correct configuration for a 99-00 car. I've just got a genuine Subaru (42072AA011) filter out of its box and it looks like the middle and right hand items in your picture, not the one on the left. I've seen and used the type on the left before, and if you install one you end up with the the pipe from the filter to the manifold sticking out because it is now too long. Might be that a previous owner of your car has fitted one and shortened the pipe a bit to suit, and then another filter replacement back to the "proper" type now finds the shortened pipe is a bit too short.

However fuel pipe is reinforced and unless it was seriously crimped, this is unlikely to be a factor in your hesitation issue.

If there was a problem with your old filter it's more likely to be cr*p buildup in it than anything to do with the configuration of the pipes on the top. However, as above I would bet a considerable amount of money that this right/wrong filter thing is a complete red herring.

Indeed. How much oil did you say there was in the boost pipework, before you cleaned them?

prodrive.greeny

iTrader: (3)

Well thats the part number i got off Subaru, and that number cross referred directly to the filter on the left of the picture. Plus the new shape fitted the pipes better (no stretch).

But oh bollocks Splitpin stop pissing on my fire with your knowledge, i thought i'd just solved it thinking the filters had a different inner core.

RE the pipework, none of it was really bad and you could easily blow through the pipes when they were all off, (the only thing restricting the air flow was the pill), just a fair bit of residue on the outside (i did get a picture of it), but most residue was on the actuator join

Bas!ard thing is i'm not going to get access to the car now until i get back from holiday (leave late tomo night) for 10 days, so i guess i'll resurrect the thread on my return. Hopefully though the Scooby fairies will come down and bless my car whilst im gone

Bob Rawle

As mentioned the fuel filter thing is a red herring.

Plugs at 0.8 will misfire, gap to 0,65mm, out of the box they are not set correctly.

cheers

bob

leecalcars

iTrader: (37)

good read guys having the same problem with my00 uk turbo also ,did a full ecu reset today problem solved,after putting the old maf back then filled up with v-power took it out for a run and bingo back to holding back again,tried the new maf ,connectors together ,full ecu reset idle all over the place very confused will jgm be able to sort this out as im getting pissed off with it now !

prodrive.greeny

iTrader: (3)

*UPDATE* - PROBLEM SOVLED

Haven't been anywhere near the car for a few weeks hence no updates for a while. But went on what Bob Rawle said in his earlier post RE plug gaps.
I whipped out the plugs this morning and re-gapped them from 0.8mm (out the box gapping) to the recommended 0.65mm. Problem solved!!!!!

Conclusion: anyone with a misfire like this you need to get your plugs out asap and check the gap size with a proper plug gap measurer and then re-gap accordingly to 0.65mm

Thanks so much for everyones input, namely Splitpin and massive props to Bob for coming up with the solution