4AGE misfire and crap idle

[lach]

hi,

My 4age (ae82 model) has got a misfire from about 1500-3000rpm. Also it is very jumpy at idle and will sometimes cut out. I have changed the spark plugs today which were pretty dirty (they had only done 3000kms), also the leads are pretty new.

Any ideas what it could be guys? I need to get it running before next week.....it's my daily. :worried:


sorry if this has been covered before.

[lach]

has got alot worse now. The car sputters and pops so i'v stopped driving it. Seems like something with ignition maybe? Can anyone point me in the right direction to things that could possibly cause this problem. I need to fix it asap.

[timbo]

heh, been here... check your timing. ive just done a belt change and realised the TPS is stuffed though :s

-check spark from coil
-take off the top timing belt cover and manually crank the engine to TDC and make sure the timing marks line up
-check leads

i think if you have fouled plugs its running rich?

[slide86]

you need to eliminate if it is just one cyl that is dropping out.

once you have established this, then you can take the next steps to fix the problem.

while the car is running, remove the plug leads one at a time and replace them. if the idle drops when you remove a lead, then that cyl is working fine. If there is no change when you remove the lead, then that cyl has a fault.

so for instance, start engine:
- remove lead no. 1......idle drops = no 1 cyl fine. refit no 1 lead
- remove lead no 2.......idle drops = no 2 cyl fine. refit lead
- remove lead no 3.......idle stays the same, no difference = fault on cyl 3. might be lead or plug, or injector

remember, a faulty injector will give the same symptom as an ignition fault.

if the fault is across all cylinders then id be looking at the coil, cam timing, fuel pressure

[timbo]

^ word.

[ke70dave]

do an ECU diagnostic test first. that will tell you if a sensor is giving an error.

and do what slide86 said.

[lach]

thanks alot guys. Will give it a try and see how i go.

[rolledup]

you need to eliminate if it is just one cyl that is dropping out.

once you have established this, then you can take the next steps to fix the problem.

while the car is running, remove the plug leads one at a time and replace them. if the idle drops when you remove a lead, then that cyl is working fine. If there is no change when you remove the lead, then that cyl has a fault.

so for instance, start engine:
- remove lead no. 1......idle drops = no 1 cyl fine. refit no 1 lead
- remove lead no 2.......idle drops = no 2 cyl fine. refit lead
- remove lead no 3.......idle stays the same, no difference = fault on cyl 3. might be lead or plug, or injector

remember, a faulty injector will give the same symptom as an ignition fault.

if the fault is across all cylinders then id be looking at the coil, cam timing, fuel pressure

said it all

[joeschmo_57]

mine kind of does that, but only when its cold, or when its a rainy/humid. when its warm it runs like a dream.
and it only started doing that after a service (i did overfill the oil though)