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Hesitation under acceleration
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Old 28 Oct 2009, 09:41 AM   #1 (permalink)
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Hesitation under acceleration

My "02" WRX Wagon has a slight hesitation when accelerating hard, most noticable in 2nd. Feels more like a boost wobble rather than a missfire. Any ideas please. Sticky wastegate. Fubbered solenoid valve. Anything else I should look for?

Run smooth at all other times.
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Old 28 Oct 2009, 10:17 AM   #2 (permalink)
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Re: Hesitation under acceleration

Hi Malc. You could clean the hoses from boost solenoid.

Link: CLEANED BOOST SOLENOID
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Old 28 Oct 2009, 10:50 AM   #3 (permalink)
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Re: Hesitation under acceleration

Thanks Pete. I'll give it a go at the weekend
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Old 28 Oct 2009, 11:35 AM   #4 (permalink)
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Re: Hesitation under acceleration

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Thanks Pete. I'll give it a go at the weekend



Make sure you connect the the pipes/ hoses from the solinoid the correct way round when you've cleaned them.
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Old 10 Nov 2009, 10:36 AM   #5 (permalink)
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Re: Hesitation under acceleration

Done a bit of pipe cleaning. Hesitation still there but done a bit more testing
and it appears to be a "flat spot" at about 5000 rpm in 2nd and 3rd gear. After 5K she really takes off, up to the red line. Is this a known flat spot?
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Old 10 Nov 2009, 11:31 AM   #6 (permalink)
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Re: Hesitation under acceleration

Malc have you replaced the plugs yet??

mine did this a while back..
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Old 10 Nov 2009, 01:00 PM   #7 (permalink)
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Re: Hesitation under acceleration

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Malc have you replaced the plugs yet??

mine did this a while back..
Not yet. Due for a service soon. Plugs are a definite as it miss's the odd beat at tickover as well.
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Old 10 Nov 2009, 01:18 PM   #8 (permalink)
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Re: Hesitation under acceleration

that could well be the problem then,make sure you get the NGK7's,cooler running temps..
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Old 11 Nov 2009, 10:46 AM   #9 (permalink)
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Re: Hesitation under acceleration

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that could well be the problem then,make sure you get the NGK7's,cooler running temps..
Do you mean PFR7B? Mines a stock engine. Some peeps seem to favour PFR6B's. Is there any reason? Dumb questions, I know.
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Old 11 Nov 2009, 02:13 PM   #10 (permalink)
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Re: Hesitation under acceleration

i do indeed,7's will be fine,just put a set in my mate's standard wrx,he noticed a differance on his trip to Exeter yesterday..
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Old 11 Nov 2009, 02:20 PM   #11 (permalink)
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Re: Hesitation under acceleration

"7"'s it is then
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Old 08 Dec 2009, 09:07 PM   #12 (permalink)
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Re: Hesitation under acceleration

Hi, just wondering did the plug change solve the problem? im having similar issues with mine...
Thanks
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Old 09 Dec 2009, 11:59 AM   #13 (permalink)
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Re: Hesitation under acceleration

Have you decatted the car ? If so it will be overboosting (worse in colder weather) and will appear flat after that as it reigns itself in.
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Old 09 Dec 2009, 12:53 PM   #14 (permalink)
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Re: Hesitation under acceleration

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Hi, just wondering did the plug change solve the problem? im having similar issues with mine...
Thanks
Sorry mate not done it yet. Been too busy trying to finish the kitchen off before Christmas. Daren't play with cars until thats done
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Old 09 Dec 2009, 02:30 PM   #15 (permalink)
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Re: Hesitation under acceleration

Exhaust leak somewhere? so lack of back pressure affecting wastegate?
this will give a laggy feeling and then an overboost at high speed?
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