Jen

I'm posting this for a friend, she brought her Sti7 after we brought her old MY98 from her and now appears to be having a few problems...she posted this on IWOC, but I wondered if you guys might have a few more ideas? It's quite long

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Many thanks to all of you for your input and thoughts on my new age exhaust question, now just to throw a spanner in the works it appears that it may not be because of the exhaust at all as I am experiencing the same intermittent hesitation with the standard back box refitted, I am concerned this may be related to a strange noise that I had when running it in, this was a strange buzzing noise occurring as the turbo started to spin up at 3k then again at 3.5 and stopped at 4 when it came in hard,( we checked the
heat shields etc to make sure they weren't resonating) but found nothing, my dealer could not find a cause and it mysteriously disappeared just after the 1000 mile initial service,

Also after a long chat with a dealer it seems that the power delivery isn't as smooth as it was on the older style cars, and he has also said they it may be down to the engine being tight(currently 1600 miles). All said and done I can't help being a little disappointed that my brand new car(completely unmodified and standard rear box back on) runs well sometimes and yet the very next day it doesn't rev as cleanly and feels sluggish over
5k revs especially in the higher gears, noticeable enough for the passenger to comment.

I think perhaps I am best to take it on a rolling road and put the
diagnostics on it because my local dealer said that if there was anything inherently wrong the engine management warning light would flag it.... but it hasn't so I am left with a car that everyone says should be OK but doesn't feel like it!!!!!!

any thoughts anyone.. oh and before I get roasted the buzzing noise wasn't the change up buzzer!!!!
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I'll pass on any comments...

Thanks, Jen

ukhuskynox

Jen,

I'd take it to another dealer, and see what they say !

KrisBennett

I can't help you with your post, but I am getting something similar in my STI7 Prodrive, as the RPM builds it makes a distinctive vibration-like sound at 3000, 3500 and 4000.

If I am gentle with the accelerator I can make the noise louder as the needle on the tachometer moves more slowly throught the 3, 3.5 and 4k makers. Above 4000rpm the noise is obscured by the rising background noise from the engine.

The noise/vibration started from about 900 miles (which was last friday), I had the 1000mile service on monday afternoon. I am now on 1050 and its still happening, I had my fingers crossed that the service was going to clear it, but no luck.......I am guessing that everything is still too tight and just needs to loosen up........if not its going back to the dealer for investigation

Kris

russell hayward

No strange noises here, but certainly have a slight hesitation issue, especially when getting back on throttle after cruising.

Pretty sure this is a mapping issue. Not confirmed, just my feeling about it.

Using 97 RON fuel really improves the car.

Also seems to be improving as more miles go on the car. It was certainly the tightest by a long away out of the 4 new Imprezas I have had.

Jen

Thanks for the replies guys I'll pass on the comments...

I'm positive she would use nothing less than 97ron fuel, so that might be out of the running...

I'll let you know anymore progress...

Anyone else?

Jen

EvoRSX

Jen,
Slight hesitation may be due to fouled spark plugs or may be an ECU mapping problem.
Well worth pulling the spark plugs out and having a look at them to see if they look OK. What may have happened is that during the running in period, the spark plugs haven't been able to get up to operating temperature and have fouled, causing poor performance. If they are fouled then a good blast out for 15 -30 mins normally cleans them back up again.

Andy