Post
by Chris1981 » Wed Mar 21, 2018 2:49 pm
A blocked CCV system won't account for your performance issues, but if you've got a significant amount of oil in your inlet and high oil consumption then it definitely sounds like it needs changing. I've changed CCVs on both my car and another forum member, we both have the lumpy idle issue but a new CCV system did not cure it. You can test your CCV by blowing through the pipe exiting the rear of the rocker cover into the CCV, if you hear gurgling oil it's clear, if not then it's blocked and you'll be blowing air/oil straight into the intake.
Not too sure on what determines the fitment of new/old CCV systems, but like PH001 mentioned if you have a silver engine cover it's likely yours will be external and can be replaced. Mine is a 2008 coupe and I have the external CCV, I've seen 2006 models that had the CCV integral to the cam cover.... of course mine may be an earlier build and registered late or had a replacement engine at some point in it's life!?
I've had a lumpy idle since buying my coupe, only appears when warm and usually when I'm using light throttle such as car parks or in traffic... blipping the throttle levels it out, does this sound similar to yours? My flat spot sounds exactly the same as yours but was a more recent thing and led to me changing coils, DISA and MAF
Vanos Solenoids - Had an error code and EML, no improvement on lumpy idle but helped with power delivery.
CCV system - reduced oil consumption, lumpy idle still exist.
New Coils - slight improvement in throttle response but nothing else. Mine were original at 95k so no harm in changing them i thought!
Large DISA valve - I did eventually get an error code for this but mine was clearly broken, if it can be moved by hand then it's shagged so quite easy to check, at £250 from a dealer you'd want to be sure this is the issue before changing! This removed flat spots at low RPM only but not the lumpy idle.
MAF sensor - after cleaning mine several times and getting slight improvements I eventually bit the bullet and bought a new one, I have not had the lumpy idle since, flat spots are pretty much non existent now and performance dramatically improved.
I tested my MAF by doing the same journey with it plugged in then unplugged the next day to see if i could feel any difference, the flat spots improved when unplugged so decided to change it. You will get an EML by driving with the MAF unplugged but the car drives fine but fuel economy will be horrendous, you'd need to be able to clear the codes after that sort of test though!
This is only my experience so cannot guarantee it will resolve your issues but wanted to share with you before you go throwing too many parts at it. I'd be happy to put my MAF into yours to test if it resolves your problems before you go buying a new one but i'm based in Rugby so would be a bit of a journey for you!? I managed to get a genuine part from eBay for £150 which is far cheaper than I can get from a dealer even with my discount!
E86 Coupe 3.0si Sport - Montego Blue, Pearl Grey with Piano Black dash
BC BR series Coilovers, powerflex bushes, 15mm spacers, Custom SS exhaust, CDV delete