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loss of power while accelerating

letemlaf
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letemlaf Rising Star

letemlaf

Posted
Posted

hey guys

i had my car's timing belt changed and dyno tuned this morning.

i have noticed this afternoon that when i accelerate it completely loses power like the fuel has just been shut off and you get whiplash from that alone.

any ideas what this could be?

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https://www.sau.com.au/forums/topic/41029-loss-of-power-while-accelerating/
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letemlaf Rising Star

letemlaf

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it seems to be fine now

it was only on my way home from work it done it.

when i went out that night it done it just a touch, but most peopel wouldnt notice. today i given it a little squirt and it seemed fine.

maybe tomorrow night it will do it again :P

AutoTrust Mentor

AutoTrust

Posted
Posted

If it does it when it the air temperature is cold, it is overboosting and giving a fuel cut, you should probably run a lower boost setting when this happens. this happens to my car at partial throttle when it is cold, if i give it full throttle it is ok as the boost bleeds off enough to stay in the safe zone.

or it is something completely different!! :P

Cake Mentor

Cake

Posted
Posted

mine did this tonight, felt f**ed

last week i had fuel pump upgraded, spark plugs changed to ngk coppers at 0.8gap... car never used to do this before, and even yesterday i have revved it out on full boost and it was fine. happened tonight on 3/4 throttle on boost at low revs 2-3k, engine fully loses power and gives u mini whiplash and then keeps going along as if nothing happened. if i keep it off boost until revs are higher than plant it, it's ok.

also since had fuel pump upgraded and plugs changed, seems as though theres a slight miss at idle every so often. can feel a slight pulse every now and then at idle. any ideas?

AutoTrust Mentor

AutoTrust

Posted
Posted

If your fuel pump flows more then there will be a pressure increase at the injectors resulting in more fuel being injected. Therefore the idle is richer and will change the way the engine idles. Whenever you change the boost, fuel system, or intake (Intercooler) you need the ability to tune the engine to achieve ideal air fuel ratios. This is why aftermarket computers and fuel computers like the safc are so popular. I need one for my car and the only mods i have so far are increased boost and a cat back exhaust.

  • 1 month later...
ecenshu Rising Star

ecenshu

Posted
Posted

Keep us updated on this issue because my car recently has this problem as well. Runs fine most of the time but once in a while (but more often when cold) stutters at 2-3k rpms. I also noticed my oil pressure rising when this happens...if I let it idle a bit(step on clutch) then accelerate again, all is fine until oil pressure rises and it stutters. Only problem is that it doesn't do it all the time.

I'm looking at the spark plugs over the weekend and will post again about it.

PS: car also had timing belt changed recently!

EDIT: I know this thread is old, but it is still unresolved IMO! :blah:

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