2000 c4 flat spot please help

[davebigrims]

hi this is my first question although iv used this site for ages as it seems there are a lot on superb members

please help me with this one problem

2000 c4 with m9604 engine

after upchangeing at around 5500rpm regular change the motor feels realy flat and picks up slowly then seems ok again

if i do hard change at 7000rpm the point of flat is bypassed and the car pulls as normal

there is no flat spot in gear ie through the revs from 3-7000 although it seems power is down a little from before also the idle is a little rough

i suspect that the fuel filter is blocked or some fuel problem or maybe im miles away

i changed the air filter recently should i have d/c battery so the management learns as the old filter was a disgrace

iv changed the plugs ran injector cleaner through not fixed though please help :rolleyes: :rolleyes: :rolleyes:

davebigrims@hotmail.com

[Loren]

I would check the for fault codes and also find a tool that you can check the MAF with (i.e. Durametric, PST2, or PIWIS tester).

[win911]

As for the rough idle....try cleaning your throttle body.

[Slideorama]

Hi Dave,

I'm very interested in what you find with regard to the flat spot.

I too have a flat spot which only appears at about 5500rpm. I'm ordering a durametric at the moment, but I have been finding the car a bit sluggish in general. I've cleaned the throttle body which fixed an idle problem but the flat spot is still there.

Good luck with your problem,

Brad

[davebigrims]

hi all thanx for the replies

i have the durametric and it didnt show any new codes so i cleaned the maf and throttle body and it now works perfectly although i have a new problem

i tried an old trick that i used to use when cleaning parts back in the day

find a smallish glass that the maf fits into

use the cleaner with straw and spray clean the maf allowing the cleaner to fall into the glass

when the glass is half full put the maf in sensor down

put the straw into the cleaner and continue to spray energising the fluid and createing bubbles etc

fill the glass to above the maf

then heres the genius part cable tie a vibrating item like a razor or ladies fun item and wait 10 mins and hey presto the cleanest maf you have ever seen and not a q tip in sight and no danger of damagimg your maf

towel dry on kitchen roll the refit and enjoy fresh new feeling engine

im quite happy to do the same to anybodies maf if you need it

regards dave

[phillipj]

That's awesome ...I want pictures :P

[1999Porsche911]

hi all thanx for the replies

i have the durametric and it didnt show any new codes so i cleaned the maf and throttle body and it now works perfectly although i have a new problem

i tried an old trick that i used to use when cleaning parts back in the day

find a smallish glass that the maf fits into

use the cleaner with straw and spray clean the maf allowing the cleaner to fall into the glass

when the glass is half full put the maf in sensor down

put the straw into the cleaner and continue to spray energising the fluid and createing bubbles etc

fill the glass to above the maf

then heres the genius part cable tie a vibrating item like a razor or ladies fun item and wait 10 mins and hey presto the cleanest maf you have ever seen and not a q tip in sight and no danger of damagimg your maf

towel dry on kitchen roll the refit and enjoy fresh new feeling engine

im quite happy to do the same to anybodies maf if you need it

regards dave

I soak mine in a jar of motor oil overnight and then just spray it with Gumout carb cleaner the next day. Oil is a good cleaner. Orginal MAF, 70,000+ miles.

Edited November 18, 2009 by 1999Porsche911

[RatboneRanch]

That's awesome ...I want pictures :P

I got distracted when I got to "ladies fun item." :huh:

[davebigrims]

hi all again

i couldnt think of anything else to call the thing i thought plastic porker or lady smile giver

so iv now done 200 miles and the flat spot is definately gone :D

although iv now got the p1341 cam actuator virus so i think im going to check that out at the weekend

does anybody have idiot proof directions to check the wires colours volts etc i have a good multimeter and a sense of humor so any help would be great :renntech:

i love my 2000 c4 aero kitted beast its got 130,000 as of yesturday iv done loads of work on her including a clutch so im handy but im no expert

push from the rear and repeat until delirious

regards dave