darren-h

my 99 seems to be holding back then surging over and over again at higher speeds so ive put a new maf on it and cleaned out the boost solonoid pipes and its just had a full service but its still doing it.ive been told it must be a problem with the ecu its an 801 and apparantly these are prone to faults,does this sound right to any of you lot? i dont want to any more money if its not going to fix it.i know someone with a brand new 802ecu if i need this how much do they go for? thanks

ian10

did you reset your ecu when you changed your maf ?

to much oil in your engine , boost solonoid need cleaning ?

a couple of options for you to try !

darren-h

i dont really know if the ecu was reset the car was holding back before the maf and everything were changed and the pipes cleaned. would the ecu need reseting for the new maf to solve anything?

ian10

if the old maf was not working right the ecu may have adjusted its self to compensate any voltage issues. On 99 cars maf's are a weak point on the car.

have you modded it any way since it started doing this ?

darren-h

no i havent touched it.

ian10

try reseting your ecu, via outo electrician and also read any error codes that the dionostic machine is showing cost you about £20
the list of things to check goes on and on do the above first

darren-h

apparantly the diognostic machine didnt show any faults.so il find out if the ecu has been reset.anything else after that?i havent had the car very long but its starting to bug me a little. cheers

ian10

if the ecu isn't showing any codes that should elimate all electrical faults ie failing plug etc
but saying that i'm not sure how good 99 ecu are for showing codes for plugs (as my car is 2003 and does show a failing plug).
next thing is a boost issue maybe a leak or over boost what mods has the car got ?

darren-h

everything has been checked for leaks too and all is fine.its got a prodrive exhaust and de cat and its supposed to have the prodrive ecu or a mapped ecu so basically ppp but i only have the sellers word for this as it wasnt fitted from new and theres no certificate and he didnt have the work done.the guy who checked the ecu numbers would have noticed a proper prodrive ecu right?by the way the car was cheap enough not to be bothered by the ppp.