need help. 1jz problem.

[COS25T]

hi guys.

i was sitting at the lights this morning and the revs dropped down and almost stalled then went back to normal. i thought it was weird but didnt happen again so i forgot about it.

this afternoon as i drove home it happened again but when i took off it was drove like shit. through first and second the revs kept dropping off than coming back again every couple of seconds. once cruising at higher speeds it drove fine.

some please tell me its an easy fix cos i dont need the stress at the moment.

[Officer Doofy]

Checking for codes from the ecu would be a start......
Could be plugs, coils, igniter, ecu.....

[acmtt]

If you have a fuel pump ecu, try to bridge it to run at 12v contiunous. They run at 9.6 until they hit boost then switch , often they die and won't run unless bridged. On a jzz30 you paperclip in the diag port. B+ and fp.

[COS25T]

been driving around today and seems fine. hopefully it stays that way.

thanks guys for your advice.

[131OWN]

I would also check the caps in the ECU as they are probably leaking which has similar symptoms

[nitros13]

sounds like ignitor to me. had the exact same problem, turned out to be a corroded conection between the igntor and the plug.

[COS25T]

got it in the mechanics right now. hopefully they can figure it out.

[COS25T]

problem is back but ten times worse. wont idle without throttle. coughs and splutters when driving.
it seems to get better when using about half throttle but as soon as i back off a bit it happens again.
i checked the ecu and everything seems fine. only one slightly leaking capacitor but i dont think it is enough to cause a problem.

[forey]

maybe needs a ISCV clean?

[richzx]

I think you will find that a leaking capacitor is enougj to cause this problem, get it fixed and check the tracks and you may have solved your problem. This has been a recurrent issue with the same symptoms.

[Officer Doofy]

i agree, did you replace all the caps or just the one that you could see leaking. It can be very hard to see faulty ones untill they are removed, same with damaged tracks. HAve you pulled any fault codes from the ECU?? Does reseting the ECU make the problem go away but come back later??

[COS25T]

the iscv was blocked shut the first time this happened. since then its been fixed and should be working properly.

does anyone in the prospect area have a ecu i can test to eliminate it

could the crank angle sensor cause this problem

[Admiral coFF33]

could be worn spark plugs creating a miss
could be fucked out ECU
could be cloged up ISCV

test those first, forget about your crank angle sensor

[COS25T]

i didnt fix cap as im not good with electronics and had no car to take it somewhere.

changed spark plugs this morning. every cylinder is firing.
just feels like its getting spark in the wrong order.

[Hydra]

Stupid question time: Do you have the coils plugged in in the right order?