A&Q about 350Z
Q:
l'll post this one here as its more electrical question...
Im trying to see if the air flow meter is giving the correct resistance through out its range.
If i measure between pins 1 and 4 thats the air temp sensor, thats ok.
If i measure between pins 3 and 4 i measure the the resistance of the potentiometer thats seems to be in spec.
What readings should i be able to get measuring across pins 2 and 3, which is the changing value as the flap opens and close's?
Just says that the resistance should fluctuate which it does, but gives no values..
This is on a '92 mk3 8V GTI, digifant 2(?), 2E engine
A:
i am just emailing you the specs mate
A:
ello mate, thanks again! I think thats what i measured but i will have to check again.
These figures are differant to the mk2, which would make sense i guess even though they look like the same unit. Thats what i was going by.
What does it say about the air temperature probe?
Ive just changed my fuel filter, the car seems better but theres still things not right. maybe i should look at the fuel pump as well... will it ever end?
Thanks again speedy!
A:
whats the exact problem with the car? i take it the lambda sensor was ok then?
A:
Hi speedy
Got a copy of autodata now so no more hassling you for info! cheers for all your help though
As for the problem l'll try to keep it short...
Brought car, gave it a service drove fine for a few months.
Had an issue with moody lambda sensor wiring, rewired and made good.
Drove fine for another week.
Started to miss-fire, hestitate.
Tryed the following.. (already changed plugs, leads, disto, rota, air filter etc)
Coil,earths, cleaned throttle body, ISV, breather hose's, replace vacuum lines, checked relays (x relief, fuel, ecu) checked / cleaned engine sensor /ecu connections.
Back to old plugs / leads (for a few days!)
Just changed fuel filter, has improved things alot but still something in the back ground..
Noticed last few days when starting from cold (later at night..) seems to miss / lumpy for a while while it warms up. Infact its a cyclic missing as if a cyclinder isin't right. Seens worse under load. Could well be mixture, as it seems to run quite rich from cold. Maybe its got worse?
Also idle a bit lumpy, engine jumps a bit now and again. Dont think its ISV. breather sytem maybe?
So fuel pump? temp sensor? MAF? maybe lambda when warmed up though looks ok in VWtool, but maybe getting lazy. Think ive got a few problems all together!
Will check the MAF and temp sensor again tomorrow now i have better data to go by.
wotcha think!?
A:
i am thinking either the intake boot has a split in it or one of the vacuum lines has split or gone soft and is closing up under vacuum did you change all of them? did you check the temp sensor? as my mk2 8v did silly things with that gone
A:
Intake boots ok, i checked all that when looking for vacuum leaks.
Cleaned it as well, infact cleaned everything!
Ive changed all the vacuum lines (3 off)
Ive got my AFM apart, the track is fairly worn in one area. must be where it spends most of its time
Ive cleaned the track with some top precison lubrricate for conductive plastic / carbon based tracks. I work in the PA audio world and we use this stuff on channel faders and pots on very expensive mixing desks and the like.
Also cleaned the wiper.
Resistance readings are a bit off, and jumps where the worn part is (i can see white substrate through the black track!
l'll try and find a another s/h unit as these are expensive as far as i can make out.
Im going to check the temp sender in a bit as im still at work so its easy to do here.
l'll add some pictures of the internals of the AFM to this post..
A:
my 8v afm meter is worn and co does what it likes! i got it rolling roaded and set up then took it for its mot 3 weeks later and it was though the roof. if when you changed the fuel filter it got better that suggests fueling, have you put some injector cleaner through it?
A:
These cars are great when all the sensors and stuff is new but when things got out of tolerance it seems all hell breaks loose
I dont know what my CO2 is, though its was MOT'ed about a month ago..
The filter does suggest a fuel problem, i might feel the need to check the pump in tank, might be a some debris floating about..
Every had you fuel pump out? Is it fairly easy process? Ive just got the one in the tank.
Everything ive done so far has been a good thing, so im not so bothered about the time spent. I just want to get it all up together as best as i can for a 14 year old car..
Heres a pic of inside the AFM
The laser trimmed resistors are mad! You cant really see it but its worn, about a 5th of the way in from the left you can see the white substrate thats under the track
I wonder if you can just get hold of the resistive track part, it just un-screws.. ( i doubt it...)
oh, i was putting a shot of redex in the tank at each fill up, i wonder if thats a side effect of whats happening? I brought a 1L bottle for cheap money.
I wanted that Redline ST1 stuff but i couldnt get at the time. maybe l'll try online.
I had read somewhere that BMW spec the stuff for there own cars but that seems to be miss-imformed. The guy at the dealer (and a mechanic) said BMW dont recommend any fuel additives at all..
A:
yer i can see were its worn that can't help but i don't think its that causing your problem. it does sound fuely have you got a spare injection rail and injectors you can try? or have you checked the resistance of the injectors?or maybe the diaphagm in the fuel pressure regulator split and not giving you enough fuel
A:
Think your right. Ive got another comming, £5 on ebay. Proberly just as fooked, but see what turns up..
Not 100% proven yet but ive noticed ive been getting white sludge build up around the breather hoses and PCV Valve. Its not under the filler cap or the port for the PCV Valve. Its getting worse as well.
I cleaned it all out a week or so ago and its back with avengence..
Cleaned again yesterday before i set off back home late evening and it didnt seem to miss (that i noticed)
Think im looking at mixture contamination from a failing head gasket or other problem.
Have you ever had you oil cooler off?
A:
yer i had an oil cooler go on my old mk2 8v gti it dumped the entire contents of the sump in the water and knocked out the bottom end their esay to change just take off the oil filter and hoses then theres a 30mm nut (i think) holding the cooler on
A:
Do you think that water could get into the oil from there?
Not seen ant oil in the water..yet
Cars done 121k so what are the odds of the head gasket? dont think the cars been completely thrashed in its life and has been regualy serviced as far as i can make out.
A:
yer it can go either way, do a compression test that should tell you if the head gaskets gone.