1JZ starting problems

[ajharriman]

Hey guys. My JZX90 has been having problems starting for a while, and I was hoping for some suggestions on what may be the problem.

Basically, it the engine cranks over for ages before it will actually fire up. It always works eventually, but can often take up to 30seconds. It seems to fire up way better in the mornings when it hasn't been running for ages, and is especially bad in the heat of the day. As it is cranking over, there is a really strong fuel smell. I'm guessing it may have something to do with the spark - maybe even just th espark plugs, but I don't really have too much mechanical experience. It seems to perform fine other than that except for blowing some smoke occasionally at high revs and poor fuel economy (which I expect may be common for a 1JZ).

Any helpwould be greatly appreciated, thanks...

[PlacentaJuan]

check/change spark plugs...?

[woggin]

if there is a really strong fuel smell it could be leaking fuel rail/injectors (i havent figured out how that fits with the "it seems to fire up way better in the mornings when it hasn't been running for ages.") But it would xplain it not stating in the heat of the day.

check over the enitre fuel system and see if there is visible petrol on the fittings/lines/rails/injectors/etc.

Then check over the ignition system..coils/leads/plugs/etc.

if the problem is still there, check for codes..

if it still aint working its got me puzzled!


wog

[ajharriman]

thanks for the help guys, I think I'll check the plugs - if it's not that than its got me puzzled.

[Xistant]

try fresh plugs and come back to us.

[pato]

definatly sounds like plugs to me

[ajharriman]

Ok, I have a bit more info.......
The error codes are:

21 - Fault with the o2 sensor
26 - air/fuel ratio too rich
31 - MAP sensor or ECU

Other symptoms are that I have gone through 2 sets of spark plugs in about 6 months, which I guess is due to running too rich.

I was wondering if anyone else has had similar issues? I don't really wanna replace the ECU and MAP sensor unless I really have too. Does anybody have any ideas??

Cheers fellas

[ajharriman]

Ok, I have a bit more info.......
The error codes are:

21 - Fault with the o2 sensor
26 - air/fuel ratio too rich
31 - MAP sensor or ECU

Other symptoms are that I have gone through 2 sets of spark plugs in about 6 months, which I guess is due to running too rich.

I was wondering if anyone else has had similar issues? I don't really wanna replace the ECU and MAP sensor unless I really have too. Does anybody have any ideas??

Cheers fellas

[Hydra]

Can you swap in a known working MAP sensor or ECU to test?

Does it help to hold the throttle open when starting?

Is the ISCV working?

[CrUZida]

I'm guessing capacitors in the ECU are now fubared.
Change them and see how that goes.

[ajharriman]

I'm fairly sure the ISCV is working properly as it idles fine, once it starts.

Unfortunately I don't know anyone who has a ecu or MAP sensor to test on my car.

In regards to the ECU capacitors... I've read alot about how they tend to leak after a while. What are the usual symptoms from faulty capacitors in the ecu?

Thanks for your replies so far

[CrUZida]

Hard to cold start, idles rough, uses extra fuel.

[ajharriman]

Ok thanks.
Sounds like a different issue I think

[ajharriman]

Does anyone know where I might be able to find an MAP sensor and/or an ecu and o2 sensor? Direct from toyota is a fricken rip off!!

[CrUZida]

Changing the caps will cost about $10 and a couple of hours.
The 1JZ ecu is by far the most common ecu to have failing caps so honestly, I'd start there.