basically ive got an MOT on thursday and i really don\'t want to be failing, at the moment the only thing that could let me down would be the emissions.
Now ive been told that you can play about with the emmisions using 3 screws, one on the idle screw (thinks thats right), one on the end of the throttle cable(at least i think thats where it is) and one on the afm. I have no way of measuring the emissions or how rich the car is running etc so how do i sort this is out? Or am i going to have to pay someone to do it?
cheers
hummm my egi passed no probs with no air pump and no cats - so you might just be lucky ??
yea but if im unlucky i dont get to have my car at uni for ages :(
Just do the usual thing. Give it a good run out and blast as much crap out of the exhaust as you can. Make sure its nice and warm when its tested. Take it to a RX friendly testing station. If you haven\'t had problems with it in the past and its not showing signs of anthing different then dont worry about it. The test for these cars isn\'t as servere as for newer cars that have CAT\'s. If it does fail then start looking into altering the screws for the idle etc. Cause if you do it before you could end up creating more problems than you have now.
Adjusting the bleed screw on the AFM, setting low idle, using some alcohol in the tank, warming engine up first before test and using fresh spark plugs will all help to get the emissions down.
After that, remind the MOT man that he can do the \'fast idle\' test if it passes at least one of the emissions factors on normal idle, they can rev it up to 1500-2000 rpm and see if the other comes into the allowed limit.
Failing that, there is always a smog pump and one way check valve to blow fresh air into the exhaust and pull it in that way (pretty much what the stock car\'s do without cat\'s anyway)
Quote from: Prof;537647Adjusting the bleed screw on the AFM, setting low idle, using some alcohol in the tank, warming engine up first before test and using fresh spark plugs will all help to get the emissions down.
After that, remind the MOT man that he can do the \'fast idle\' test if it passes at least one of the emissions factors on normal idle, they can rev it up to 1500-2000 rpm and see if the other comes into the allowed limit.
Failing that, there is always a smog pump and one way check valve to blow fresh air into the exhaust and pull it in that way (pretty much what the stock car\'s do without cat\'s anyway)
i take it i adjust the screw when the cars running?
and whats the reason for the alcohol?
its got nice new spark plugs :D
cheers for the help
Do you still have the reburners and air pump?
Quote from: dthebuk;537668i take it i adjust the screw when the cars running?
and whats the reason for the alcohol?
its got nice new spark plugs :D
cheers for the help
Alcohol reduces the emissions as it burns so much cleaner - in the states they often take the car to the testers virtually empty but with a litre or two of ethanol in it, then as soon as they leave the testing station - they fill with pump gas, as you don\'t really want to be driving around on it without having tuned for it.
hmm i don\'t like the sound of the alcohol too much.
should i turn the screw on the afm back after the mot test?
YES! otherwise it won\'t run properly, also you might run very lean and cook the engine. I used to adjust mine just out of sight of the MOT bay on the way in and out :)
oh i bet they loved you.
um which way do i turn it? and do i just bring the car to a low idle with it?
also the air pump is gone so im going to assume the reburners are too
I\'m talking about adusting the AFM - then turn the idle mixture adjust down as far as you can and still have the car run.
The best thing to do is rig up some kind of air bypass valve so that you can let a small amount of unmetered air into the UIM - that worked for me. (My Dad\'s idea)
okey doke
i was told to adjust the idle mixture till its just about to stall and then turn the afm to counteract it.
just wanna clarify, to change the idle mixture you turn the screw on the top of the intake manifold?
nope - thats idle speed, idle mixture is black pot just behind the airbox :wave
ok so ive lowered the idle as far as it will go, which is about 500 rpm.
ive then turned the screw on the afm/behind the air box 720 degrees clock wise, doesn\'t seem to have had an effect.
ive also turned this screw
(http://img217.imageshack.us/img217/7059/photo0057md1.th.jpg) (http://img217.imageshack.us/my.php?image=photo0057md1.jpg)
close up
(http://img88.imageshack.us/img88/3604/photo0060rm9.th.jpg) (http://img88.imageshack.us/my.php?image=photo0060rm9.jpg)
i not sure what this ones called. I turned it anti clock wise 720 degrees and i think its leaned out the mixture a bit as the car isnt popping at all after being reved.
please tell me if what im doing is wrong? or if i can take it to a higher extreme, im just scared ill break her
Hope you\'re taking it to the local RX-7 owning MOT station.
Martin H
well ??????????? what happened
Quote from: noyzboy100db;538441Hope you\'re taking it to the local RX-7 owning MOT station.
Martin H
you talking about thames valley mot in reading?
i wantedto go but its pretty far away. TBH ive been soo un organised lately, that i only just got the booking for the mot before im off to uni.
havnt had the mot yet, just realise the cars running even richer...ill have a quick play about:D