3 problems with ae82 silver 20v

[andy]

Hi guys. i have many problems with my car atm(im a perfectionist).
its a ae82 with a silver 20v 4age. its been in there for a few months and ive had the same problems with it from the start. it is standard appart from a 2.25" exhaust(all the way) with high flow cat and tri flow muffler, and cai with custome air box and BMC filter. got trd leads, and bosch super 4 spark plugs(not sure i baught the right ones but seems ok).

1. when im accelerating at a slow pace it starts to lag at about 3000rpm. its a intermittent problem and goes away when ever i goto the mechaincs to show him!!! by lag i mean it stops pulling and starts spurting(a tiny backfire). if i dont move my the accelerator then it gets real bad and jerks the whole car!, if i push down a tiny bit more, it becomes unstuck and starts accelerating very quickly. this is not a problem when i have my foot to the floor. usually happens more then i have been driving quickly for a while and will happen on evey gearvery noticible in 1st-3rd, less in 4th and 5th. it really jerks your head back in 1st.

2. when im in gear on the freeway and take my foot off accerator to slow down abit the steering wheel starts shacking(only the steering wheel). this only happens when i come off the accelerator and at above 110. but there has been instances of it not happening. alot of the bushes are split and stuffed. they will ALL be replaced soon along with all shocks, springs and rear sway bar.

3. when im driving with accelerator 3/4 down and remove my foot gradually the revs drop in stages. as in it jerks down instead of being smooth. sometimes with a tiny back fire too. not sure at what revs it jerks but i can find out if it will help.

thanks in advance guys. i really hope you experts will be able to help me out.

i have had the AFM changed, and it seemed to fix no1 for about 3 days, then back to normal.

also car used to stall on random occations. got it tuned and it dosnt do that now.

[Starfire]

I don't know enough about the 20v to help with your problems there, but it sounds like new bushes and a decent wheel alignment/balance will fix the shakes in the steering.

Good luck getting the other stuff sorted out

[oldcorollas]

1 and 3 possibly TPS. if it goes AWOL for a second due to worn tracks it could cause issues..

no.2.. perhaps they should be replaced before this wobbling causes an accident?

when the car was "tuned" before to fix the stalling problem, what exactly did they do? if it is stock ECU (sounds like it sicne you still have AFM)) then what can they tune? base timing and??

[finney]

AFM is definately something to check. in regards to the stutter/lag that the car has at 3000rpm, this may be due to the variable valve timing as i believe it kicks in at this point.

[oldcorollas]

did you remember to put in an EFI filter when you did the conversion? was it new or old?

[mullett]

It's not something stupid like a loose wire, or a vacuum hose with a split in it? 9 times out of 10 the easiest solution is the right one...and you can spend $$$ looking at the most complicated things. Just go over the motor, check all the plugs, clean them, check all the vacuum lines, that kind of thing

RM.

[andy]

thanks for the reponse guys.
it had a 4age in it before so no prob with the filter. i might put a new one in just to be safe.

i changed all the vacuum hoses just to be safe and that didnt make any diff.

2. i knew it might be the bushes, thats why i mentioned they where cactus. but i was thinking that something might be out of blanace(fly wheel, clutch, etc) as its only when im in gear. if it where the bushes then the problem would happen even in nuetral, right?

i have spent hundreds of hours pondering what might be a solution for 1 and 3. i think they are related. i know if has something to do with the fuel system, but its so complex. so many sensors effect what the ecu does in regard to fuel.
im going to change the TPS and if thats not it then ill prob move onto the either getting injectors clened, replacing them or getting a carbon clean done. what im thinking is maybe 1 injector is blocked. what you guys recon about a carbon clean? i got one done on my old 4age and it ran BEUTIFULLY afterwards, but then cracked a head a few months later.
im also gonna make sure the dizzy is all good, as in another thread a guys with a 4age was having very similar problems and that was the solution.

edit: thought i should add that the problem dosnt happen on a cold engine, not that i have reved the balls out of it. but i can tell when it starts happening(almost in the same spot every morning on the way to work)

[sideshow]

drive it up to sydney and ill fix it in an hour

its prob yr oxy sensor this makes them a touch laggy

if this works ok then i prob have other issues

i have done about 150 20vs so i know everything bout the wiring

who did the wiring did they do a good job

put a noid light on the vvt solenoid plug and when engine is warmed up give it a big rev

it should light up the noid light

if it doesnt work then u have a problem

open the ecu and check bottom right section for fukt capacitors

if they are wired wrong they can soemtimes stuck the ecu internally

i have an ecu from a 20v here with burnt circuit board

[andy]

just to make sure, you are talking about the oxy sensor in the exhaust pipe?
would it also cause problems if it was mounted in the wrong spot?

the wiring was done buy toyospares in vic. they seem to know their stuff, but even an expert can stuff up.

where abouts is the vvt solenoid? i have been thinking its that.

thanks for the offer of fixing it, i might actually go up to syd in a few weeks just for a road trip if im bored.

ive added those things to the list and i will go through it all on the weekend. anyone recomend anything else?

for no. 2 could it be the harmonic balancer?(its a manual)

[sideshow]

if u come up meet me at sss automotive on a sat mornin

that way i can try another ecu and air flow meter while we are there
to see if ti fixes problem

[The Witzl]

rather than replacing the TPS, try testing that it is calibrated correctly....

To Test your TPS:
check that the IDL pin on the ECU goes to earth when throttle closed (foot removed from pedal), and that it disconnects from earth as soon as the throttle is opened less than 1mm.

Also, put a multimeter measuring 0-12Vdc between the VTA pin of the ECU and E2 pin, and drive around getting the car to do its surge-thingy.... have someone watch the voltage as this surge is happening.
Then for control purposes turn the engine off, then put car in ignition. Again measure and observe the VTA voltage whilst you gradually press the accelerator pedal down. The voltage should change gradually from around 0V-5Vdc.


You can also get your AFM calibrated on a dyno to ensure that the idle mixture screw is set correctly... have you adjusted it at all??

[andy]

thanks for tips, i will try them!
i havnt touched it, but im pretty sure it was adjusted//tuned a few weeks ago.

so what dose the tps do exactly? i thought it measure how far the throttle was open, but from the post above it seems like it only senses if the throttle is open or shut. care to clairify?

i will get a gas analysis done on sat morning to see if anything comes up(rich/lean, etc).

[sideshow]

why the fuk are the tuners adjusting the air flow meter

look at the air flow meter has the black plastic top been removed and re siliconed back on

they should not have touched it from std

it will never be as good a tune as in std form if everything else is std

[andy]

really.... the first one i had, they screwed it in and out and it made no difference at all, so they replaced it and put another one in. which they fiddled with a tiny bit. could that be the cause of my problems?
how would i go about getting it tuned back to std? dose that black thing need to be siliconed on? cos its just stuck in there atm.

[sideshow]

oh thats the idle mixtures they dont really matter much

i thought u meant they removed the lid and played with spring inside

u can play with the screw if u rev it and see how it comes back to idle

if it stalls sort of then srew it one way and see if it gets better

then if its worse screw it the other way

if the black thing looks like its been played with then its hard to say whats wrong

i would not waste the time retuning it if its been played with
unless its been marked where the original spot is

its easier to buy a 2nd hand air flow meter

see what can happen is u might have another problem and the dumb asses have adjusted the airflow meter to compensate for a problem that is not the air flow meter

u should never have to adjust the spring inside the meter

anyway yr problem is hard to explain by chattin on here

just like 50 million other problems on here

take it to someone who knows what to do

i have access to 2nd hand parts for testing up here so i can test things and not pay for them and if it fixes the prob i then ask the customer if they want to buy it

if the black thing is loose then its a good chance someone has fukt with it

so in that case if u can put it back to std and start from scratch again otherwise yr wasting yrs and everybody elses time

it just pisses me off when dickheads adjust meters when runnin std ecu

anyway guess u have some checkin to do