right there is a problem with my hgt. around 4000 in 2 3 4 and 5 you notice a big loss in power.

acceleration still goes up, but much slower than lower revs. i know this isnt right.

now first tried unplugging the MAF and driving, but it was still there, so not a MAF issue.

you guys then said maybe coil pack, or spark plugs. im gona order a new set of plugs, but coil packs you get individually. at £15 a go, dont really want to buy 5 if i dont need 5.

can you tell if the coilpack has had it without using a volt, or milimeter that i think jug was on about?

want to get this sorted,, as the HGT is real slow now, no where near its former glory

measure resistance across each coil's pins (with connector removed) using a multimeter to compare them.

dodgy lambda sensor can also cause it.

so can a blocked air filter.

and a blocked exhaust (usually cat).

i recently put on a pipercorss airfilter. could that be causing it?

on idle, you can hear it sucking in, like theres not a lot of room for air to get through.

so maybe this is causing it.

is there a different cheap filter i could get to test if this is it?

yeah a piperX could be causing it, depending on how you've fitted it and which type it is. got any pics?

Yes its same as

http://cgi.ebay.co.uk/PIPERCROSS-IN...VQQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247



i fitted it not directly to the maf, as in poic, but with a bit of silicone tube with a slight bend in it, and its fitted nicely in the wing, i cover the holes in the inner arch liner with pond liner and silicone, so it doesnt get muddy.

but even on idle you can hear it sucking in air quite loudly.v and basically its made of black foam like the one above

Really cheap to revert to original set up and see.

yea it would be had i not destroyed it taking it out :bang:

read on here people saying they just cut it in half to get it out. and for the sake of not jaking the car up, removing the wheel, and simply removing the arch liner, i cut it in half and removed it. ive never had a problem with a air filter. i perhaps ignorantly assumed pipercorss filter would be fine

unfortunately this isnt a option now.

Assuming that u now have free air flow, did you do anything to the mixture settings via the map?

no, altered anything. just put on air filter, and cat back exhaust.

im thinking it could be the filter not leytting enough air through.

on idle, it almost sounds like its struggling to suck in air, hence you can hear it sucking in air quite loudly.

i was thinking that if it was free flowing, i would hardly be able to hear it.

its almost like air escaping from somethnig, but obviously its going the other way

rema-d said:

no, altered anything. just put on air filter, and cat back exhaust.

im thinking it could be the filter not leytting enough air through.

on idle, it almost sounds like its struggling to suck in air, hence you can hear it sucking in air quite loudly.

i was thinking that if it was free flowing, i would hardly be able to hear it.

its almost like air escaping from somethnig, but obviously its going the other way

Click to expand...

I see ur train of thought, maybe try a run with no filter on, u would feel an improvement at the top end I think if its restricted air flow. My thinking was around the fuelling not matching the air volume when sucking in big volumes at wide throttle openings, but that may be controlled by the MAF etc and auto-corrected.

ok ta, and its gona be alright to take for a short burn with no filter on it?

rema-d said:

ok ta, and its gona be alright to take for a short burn with no filter on it?

Click to expand...

Maybe choose a moment when there has been rain to damp down any road dust, its ok for a very short run just to prove a point to yourself, I would never advocate running for any period of time without air filtering TBH, but u will very easily know the answer to your question by trying that.

great will get the engine warm later, and give it a whirl.

hopefully that is whats slowing it down. and ill have a monster back..

will post results...



watch this space

took it off, had a burn, and it didnt seem too bad. put the filter back on and didnt notice it doing it again. then on the way to work this morning, noticed it was doing it in 4th and 5th and just over 4000 rpm.

hmmm..

will re-check the filter after work, most puzzling

Weird... may not be related to air-flow then.....

hang on its the 20v model, the MAF is a very common cause of this problem, and the MAF would have easily been disturbed during piperX fitting. check MAF connector is ok. if you oiled the piperX then clean the MAF using an alcohol spray and dont oil your filter in future.