Pulsing acceleration
17 August 2010, 12:00 AM
#1
Pulsing acceleration
Well as u probably know I've only owned my Scooby for just over a week and
I've noticed pulsing acceleration under hard throttle. Since I've had new maf sensor, air filter, bottle of redex it's still the same. Do u think the cat-back exhaust could be causing it or fuel pump etc? Also could it be remapped without an ecu upgrade? If so do u think this good be what it needs with the exhaust? Thanks guys
I've noticed pulsing acceleration under hard throttle. Since I've had new maf sensor, air filter, bottle of redex it's still the same. Do u think the cat-back exhaust could be causing it or fuel pump etc? Also could it be remapped without an ecu upgrade? If so do u think this good be what it needs with the exhaust? Thanks guys
17 August 2010, 12:13 AM
#5
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Probably to do with the exhaust, what size is the pipework? It could also be the boost solenoid or a combination of several factors, a remap would be advisable tbh.
Tony
Tony
17 August 2010, 12:23 AM
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Yes the standard ECU can be reprogrammed by an Ecutek mapper. As Tony says the exhaust is one possible contributor to your fluctuating boost but it shouldn't be this, if the car is otherwise running 100% properly. If you had a decat downpipe it'd be more likely.
Oil contamination in the boost control pipework or solenoid is, as above, one possible, and maybe more likely cause, although there are plenty of others. Does the car have a standard or aftermarket dumpvalve, for example?
Search is your friend, although a visit to a good local specialist is likely to be able to pin this down pretty quickly.
Oil contamination in the boost control pipework or solenoid is, as above, one possible, and maybe more likely cause, although there are plenty of others. Does the car have a standard or aftermarket dumpvalve, for example?
Search is your friend, although a visit to a good local specialist is likely to be able to pin this down pretty quickly.
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17 August 2010, 12:25 AM
#8
Yes the standard ECU can be reprogrammed by an Ecutek mapper. As Tony says the exhaust is one possible contributor to your fluctuating boost but it shouldn't be this, if the car is otherwise running 100% properly. If you had a decat downpipe it'd be more likely.
Oil contamination in the boost control pipework or solenoid is, as above, one possible, and maybe more likely cause, although there are plenty of others. Does the car have a standard or aftermarket dumpvalve, for example?
Search is your friend, although a visit to a good local specialist is likely to be able to pin this down pretty quickly.
Oil contamination in the boost control pipework or solenoid is, as above, one possible, and maybe more likely cause, although there are plenty of others. Does the car have a standard or aftermarket dumpvalve, for example?
Search is your friend, although a visit to a good local specialist is likely to be able to pin this down pretty quickly.
17 August 2010, 12:34 AM
#9
Oh and as I said in previous thread I'm a bit sceptical as to what the chap I bought from said about being standard apart from exhaust and dump valve as I found a used manual turbosmart boost controller in the glove box when I got home!
17 August 2010, 08:30 AM
#10
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This car has been messed about with. The brass pill might be missing from the little connector piece by the turbo, the car needs to be looked at by a good mapper.
Where are you based?? This will have an impact on which is the best easiest mapper to choose from.
Oh and by the way, the vta dump valve will do your car no favours, get it off, sell it, put a normal one on, use the money for a more positive modification on your car!
Where are you based?? This will have an impact on which is the best easiest mapper to choose from.
Oh and by the way, the vta dump valve will do your car no favours, get it off, sell it, put a normal one on, use the money for a more positive modification on your car!
17 August 2010, 10:22 AM
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Check the spark plugs.
Had the same feeling and eventually a mis-fire due to a knackered spark plug mate. CEL only lit up when the mis-fire was sensed but the car was jerking like that on full whack for about a week before hand.
Had the same feeling and eventually a mis-fire due to a knackered spark plug mate. CEL only lit up when the mis-fire was sensed but the car was jerking like that on full whack for about a week before hand.
Last edited by Korrosiv; 17 August 2010 at 10:23 AM.
18 August 2010, 11:23 PM
#14
Update! So I've bought rear discs, pads and shoes, had loads of hassle getting the discs on when new shoes are on, took them all back to the shop and was advised to file the forks on the shoes down, now I can get the discs on but they won't turn now! Think I'm gonna take it all back tomorrow and get them from somewhere else, just don't fancy main dealers, they want £70 just for shoes and I paid £104 for the whole lot elsewhere!
19 August 2010, 10:22 PM
#18
also could be the leads so on my my97 uk turbo it was like that, changed the leads good as gold!
20 August 2010, 12:28 AM
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Ive had a few of these, standard and modified and have had the same thing with both, under normal acceleration i felt a slight pulsing, nothing i changed sorted it so i just left it.
23 August 2010, 04:22 PM
#20
*UPDATE* I've now noticed that this pulsing acceleration is present while accelerating no matter how much/little I press the throttle. I've got some ngk plugs on their way in the post (not looking forward to changing them though looks a nightmare!)
Oh and excuse my ignorance but where do I find the boost solenoid? Pics would help!
Oh and excuse my ignorance but where do I find the boost solenoid? Pics would help!
23 August 2010, 05:44 PM
#21
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The circled part is the boost solenoid.
And if you look on this thread it explains how to do it
https://www.scoobynet.com/technical-...-solenoid.html
And if you look on this thread it explains how to do it
https://www.scoobynet.com/technical-...-solenoid.html
23 August 2010, 11:37 PM
#22
The circled part is the boost solenoid.
And if you look on this thread it explains how to do it
https://www.scoobynet.com/technical-...-solenoid.html
And if you look on this thread it explains how to do it
https://www.scoobynet.com/technical-...-solenoid.html
This looks different to mine, mine is a year 2000 x plate would that be the same?
25 August 2010, 04:05 PM
#26
Gee thanks buddy! Lol
Well boost solenoid mint, pipework cleaned to no avail still!
Taking it to pole position in willenhall tomorrow, they claim to be Subaru specialists and say they won't charge me to have look so it's worth a bash! Anyone ever used them?
25 August 2010, 04:31 PM
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I thought the job was a sh1tter also, but my mate took the airbox out and unscrewed the windscreen washer reservoir to move it, and it took him half hour at the most.