Beaker,

you may be the person to ask this... What did they call the "mad-professor" character that Beaker worked with on the Muppet Show?

No-one I've asked seems to remember!

Moray

 

I think this may possibly have been covered before but hear goes anyway.

two 'intermittant' problems on an STi2

1) at full boost, approx 5500-6500 revs, 3rd, 4th gear you can feel the car begin to stutter. if you are a little more gentle with the accelerator i.e don't try to push it thru the floor everything is ok.

2) alittle more annoying, 1st gear sometime when i try to accelerate very hard from stand still the car cuts off all power to the engine which nearly knocks me out as my head hits the steering wheel. (and its not me bouncing it of the redline!!) again about 5-6000 revs.

suffering from whiplash

Craig.

 

sorry meant to add the car is due for a service any day now, I was looking for some pointers to get me started.

 

Could be missfire: ignition - sparks - coilpacks.

May be overboost limiter, is the car boosting higher recently?

Moray

 

Moray,

The name you're looking for is Bunsen. (guess who went to see ('Muppets from Space' at the weekend!)

Beaker,

I've also got the same 'stutter' issue with an STI2. Car is due to go in for a check-up week after next so if I get any more info I'll post a response.

Mart.

 

Yeah it's Bunsen Honeydew...

 

memememememe!

you haven't seen the picture they put on my wallpaper at work!

It does appeat that most of my problems revolve around maximum boost. Problem is I have no boost gauge.

and leave bunsen out of this. he always steals the limelight.

 

Sometimes when booting it in 2nd I get violent 'stutters' when I have around 1/4 tank of fuel left. Fill up and the problem goes away. Could be that.

 

Beaker, first point is probably a coil pack, check plug gaps, reduce to 0.6 and see if it improves, should be 0.7
2nd point is engine cut due to boost limit being reached.

had the same things on my car.

Bob

 

Beaker,

What induction kit are you using? I had problems with Pipercross as it introduced turbulence or "surges" to the inducted air...

Just a thought....

Gethin
MY97 WRX

 

I'll go with Bob on this..

You may have several problems...

But if the power cut is real sudden and abrupt.. like hitting a wall, then I would say over boost.. a coil pack or plug gap wouldnt suddently cause the engine to stop so abruptly...but would cause a general power loss... sometimes intermittantly at high revs...

Cheers,

J.

 

Thanks for all the replies, it does appear to be two distinct problems 'overboost' (cut out is ver violent and also very brief)in first gear, possibly coil packs in subsequent gears.

RichB, had 3/4's of a tank this morning when it happened so I guess this is probably not the cause, it did have me wondering for a while though. Does anybody else car constantly seem to be only half full?

Gethin, no induction kit.

The car had it's 30K service about 6 months ago so I'm hoping they changed the plugs, however, you can never quite be sure. It's now due for 37.5K service, so i'll get the to check the coilpacks and plugs.

What can i do about overboost?

Craig.

 

I would also agree with Bob here, I had an identical problem on my 93 WRX. The spark was actually blowing out under high boost as the coil pack was cracked and the spark was jumping around.

This is probably a noddy explanation but, I would say whip them out, remove the rubber cap and have a good look at em, it will be dead obvious.

Hope this clears it up, Richie.

p.s a new coil pack is about £75.

[This message has been edited by RichieC (edited 03-02-2000).]

 

Latest update.

Went to Power Engineering, had the service, new spark plugs, air filter, front pads, amongst others.

Went for the tune on the rolling road, first to runs averaged out at 258bhp (STi2) a bit lower than expected. When you see the dyno reading there is a big dip triangulat shaped dip at about 6200. Suggestion was that it was about 20-30 bhp down on what was expected. Cars boost was 1.0. Car would only hesitate a full boost. When restricted to 0.8, there is no hesitation. Air filter and intercooler check. No visable problems. Car was running rich (even for an impreza) this was determined as the fault. Fix? not sure.
possible soultions.

1) one of the coil packs is knackered. (no coil packs in stock)
2) my cracked heat shield front drivers side was vibrating at high revs at the same frequency that the knock sensor is trying to pick up (Knock reading did reduce when taking car out for a spin had 6200 revs reached), thus knock sensor firing early. Well if was affecting the knock sensor in someway. solution new heat shield. Comment please on this one.
3) remapp the ECu around the problem. I'd rather not spend £650 for the pleasure. Not really finding solution to problem.

Help please

Craig.

 

Beaker,

likelihood of knock sensor causing this problem are very slim. The knock control in the JECS ECU isn't that brilliant....

The hesitancy under full boost is almost certainly due to coil packs. Get them replaced (I did the lot, not cheap but well worth it) and this should fix the prob. With regard to overboosting, this could be down to a restriction in the wastegate control pipework... take each hose off in turn and clean it out with carb cleaner. Also clean out the brass restrictor (if there is one) and the wastegate control solenoid. This should help. if it doesn't you could have a dodgy solenoid.

Hope this helps,

Pat.

 

... And for (etherial being)s sake, make sure you properly secure all the hoses back into their original positions using proper clips or zip-ties!

[This message has been edited by MorayMackenzie (edited 17-02-2000).]

 

err.umm.. some stupid questions maybe!!
I have an STI2 as well that seems to hesitate occasionally now on high boost.
1. Where are the coil packs on the car , are they easy to remove and is there something I should look for if 1 is dud.
2. If I want to replace them where can I get some ?
3. This seems a common problem I would have thought P.E. might stock them. How about it Dave !!!(Still pleased with the Phase 1 by the way! creep , creep!)

 

Coil packs on top of plugs (one for each)
Available from every Subaru Dealer. Cost is around £60 - £70 EACH.
Not difficult to replace but will take some time as you have to take various other bits off first, have a look you'll see what I mean. Apparantly the ones with one screw holding them in (ours) fail more regularly than the ones with 2 as on some Legacies.

 

Thanks Paul I will have a look.

 

Guys,

I have had the 'violent kick' problem recently and my problem was due to overboost. I never had this problem in 1st gear though. Also, Beaker has not had any upgrades recently to introduce this problem. Beaker, if your engine sounds rougher than normal then thats a clear inidcation of coil problems.
I would suggest you get your boost checked (borrow a guage) and make sure you are getting enough air to the induction sensor (from the main induction pipe). The air intake sensor may be soiled or faulty. I had exactly the same problems (after fitting an induction kit) and there was not enough air getting to the sensor due to straight-through air system.

Hope you fix it soon, and drive with 90% throttle until then!

pilch