Seems I've finally managed to kill my WRX

Car is a 2003 UK WRX with 31000 miles

Symptoms are:

* Misfiring at idle
* Slight hunting at idle (used to be rock solid) varies about 1-200 rpm. Oil pressure fluctuates (consistent with hunting. when cold, 6.5-6.7'ish bar)
* almost no power at all. Car would only accellerate up to walking pace in first gear and that required lots of clutch slippage to even get to that speed.
* Once past 1500 rpm with any load it backfires, misfires, "kangaroos" etc
* doesn't go past 1500 rpm except at idle, and then only up to about 2000 rpm
* Check engine light came on after about five minutes

No mayo looking stuff on dip stick or oil filler cap. Coolant looks normal.

Tried disconnecting MAF whilst idling and it dies instantly.

It was running a little bit rough yesterday evening (at idle, it would "shake" a bit more than usual) but still ran normally (no noticeable loss of power etc).

It doesn't at this stage sound like a mechanical problem to me, i.e. there's no odd knocks or noises that haven't been there for a long time, but didn't run it up to working temperature of course so don't know if that would make any difference.


Engine mods are:

* sti pink injectors
* fuellab FPR set to 3.5 bar at idle with no VAC
* walbro 255
* apexi induction kit <---- could this have killed the maf or something if it got wet?
* sti intercooler
* lateral 3 bolt headers + up-pipe
* decat downpipe to a 2.5" exhaust
* td05-20g
* 10% E85 with vpower
* Ecutek map

Any ideas folks? Is it possible to check the error codes yourself, or does it require an odb-2 reader nowadays? Nearest subaru dealer is on the wrong side of London, unfortunately

Wife's already told me I ain't spending 5k fixing the engine

 

Would a compression test be of any use or is there anything else I can test first?

 

All symptoms point to a failed MAF despite the disconnect test.

That would be my thing I'd investigate.

 

td05 20g on std wrx internals?!!

 

Seeing as I'm almost right next to Jap Performance Parts in Crawley at the moment I'm popping over there to see if they have a used MAF I can buy in that case At least that should rule it in/out.

A bad lambda sensor wouldn't cause a problem like this, would it?

 

I thought that was standard practice on new age's

 

Oh also, if the MAF was found to be broken, does that mean another remap? Remapped about two-three months back

 

Henrik i applaud you mate!!!!

 

I don't expect it to last until the end of time, but now is a particularly bad time for it to go as my other car is in bits awaiting upgrades

 

Maf or fuel pump.
Yes lambda failure could do similar.
Try disconnecting it.
Also finding out error code migit help
Simon

 

Is it possible to check the error codes "at home" on a new age, or does it require a reader?

 

Needs a reader. Where in London are you? im in Herts and have one

 

Wrong side unfortunately Bromley area


I've just picked up a maf from jap performance parts, hopefully that solves the issue

 

Henrik - what sort of power are you running on that setup? do you have any figs without the E85 content? Just interested to see how far you went on std internals ....

 

didnt you run this on e85 without a remap?

 

me to
Mines been fine at over 400hp for 9months

 

No of course not

My current (hardware) set-up has been mapped twice by JGM.

I think it was in May (ish) last year that Simon mapped it the first time on vpower + one full bottle of NF per tank (dead expensive!). At the time I wasn't using the car as much, so the extra cost of fuel wasn't a huge problem. On the deltadash it made 353bhp / 354 lbft @ 1.4'ish bar.

However, I now (usually) drive the car to work, so go through a lot of tanks of fuel, so cost of NF is a problem. I hence had it remapped again but this time with 10% E85 in the vpower mix. Exactly same hardware but Simon was able to up the boost slightly to 1.52 bar.

It also took more timing at the low end, but less at the top end.

The result (again, with deltadash) using exactly the same settings as before were 391/392, and a much nicer drive as there's more torque further down.

There are some graphs here: http://www.bilar.co.uk/subaru/graphs

 

clucking bells, just had a look at your "view scooby". I remember JGM talking about your car actually and that it was running very well, but 401bhp - impressive

Out of interest, how much did deltadash show with your setup?

 

You can get readers off ebay for £25
Not the best but tell you whats wrong and stops you worrying

 

Its now 405.3 bhp/369lbs as pat mapped it again on tueday
Always done on the rollers at surrey

 

thats mental!! I'm tempted to go for it but use my car to commute to work everyday so would be screwed if it blew up !

 

niceeeee bugeye sounds a bit of a beast

 

as long as you dont hammer it every were it'll me fine .

 

Henrick, I'd be concerned if my boost and ignition were altered to give me another 40BHP just upon adding 10%E85 or have I misread ur post? It's like eating into some safety margins there. Hope ur cars ok buddy.
Cheers
Trevor

 

Ok, got home and started the car up again. It seemed a lot happier than this morning, although still ran lumpy at idle and kept missing as well.

Started putting the new (used) MAF on and discovered that the air filter was soaking wet Took it off and used a hair dryer to dry it out. Must have got wet from the recent rain I've been driving through.

Car now seems a lot happier. Initially it kept missing a bit still, but not as bad as before, but that seemed to clear once it got up to temp. Idle stable etc.

When I first drove it it felt a bit flat (before it warmed up), but that went away after warming up properly as well.

First time on boost, it felt like it was pulling a bit of timing (or something) around the 4000rpm mark (wasn't mis-firing or dropping boost from what I could see on the gauge).

The second time (am I stupid for trying it a second time? ) it felt fine throughout the register.

Drove a bit further and got to "my" empty dual carriage way and did a run from 30 in second up to most of third gear. Car felt fine


Unfortunately, the check engine light is still on, but I've ordered a Obd-II reader to have a look at it.



My theory is like this:

Wet air filter this morning, didn't flow enough air so ECU thought something was wrong (possibly also broke the MAF). This caused the car to run so rich that the lambda sensor readings where all over the place. Hence it's now got a check engine light on.

Does that sound plausible?

 

Renember pat mapping me car one time and road tested it in a pea soup , the filter got wet ,maf got socked . dryed the filter out a bit by shacking it , put it on the rollers , two minutes of dry air over the maf and all was fine .
So don't throw your old maf out !
Try it on a dry day it may still be o.k.

 

the cold water will screw the maf voltage reading.. ecu will think lots of air going in due to water hitting the sensor and it will chuck loads of fuel in..

Simon