2JZGE in MX83 (check engine light comes on)

[RObErT_RaTh]

Hi guys and gals,

I've recently purchased an MX83 cressida with a 2JZ-GE and a W58 and in the last few days I've been driving it the check engine light has popped on. At first I wasn't sure what was causing it as both times it happened I was accelerating up a steep hill but I realised later that it was related to speed and these hills were 80kph as opposed to the 60kph roads I'd been driving on previously in the week.

I tried shorting TE1 and E1 in the diag port and reading the codes from the light flashing but it's just a constant flash and nothing else. To my knowledge this means no error codes have been stored and everything is operating normally?

Does anyone have any clues as to why this might be triggering at exactly 80kph as soon as you reach that speed for the first time during that session of operation? If you turn the car off and back on again the light doesn't show until you reach 80kph again.

Any help would be greatly appreciated, thanks!

[wilbo666]

Interesting that the Check Engine Light comes on, but no codes are logged...

I wonder if BATT is wired up to the ECU? If it isn't then one could understand how it can't remember the codes...

Might also be worth while generating a code yourself by unplugging something like the water temperature sensor and seeing if that generates a code...

Cheers
Wilbo

[Azzamk2]

same thing happend in my 1jz ma61 after the conversion. i got told it wouldn't cause dramas and was just a speed sensor wire that would need sorting out if i didn't want the light to come on above 80kms..thats what i got told anyway been going for years now with no issues

[RObErT_RaTh]

I wonder if BATT is wired up to the ECU? If it isn't then one could understand how it can't remember the codes...

Might also be worth while generating a code yourself by unplugging something like the water temperature sensor and seeing if that generates a code...

Thanks wilbo, might do that and see if it keeps a code. If the light comes on and it doesn't keep a code then might have to double check the wiring. Cheers!

same thing happend in my 1jz ma61 after the conversion. i got told it wouldn't cause dramas and was just a speed sensor wire that would need sorting out if i didn't want the light to come on above 80kms..thats what i got told anyway been going for years now with no issues

Do you have more information on what is required to prevent it from happening? If you do that would be really helpful, thanks. By the way, did you have a modified light hooked up for check engine light in the MA61 because I don't believe they had them from factory?

The issue I have is that although the light may be coming on for no reason, if I have triggered it by going over 80 and then there IS a problem, how would I know?

[takai]

The ECU definately keeps codes, because before i had the air temp sensor hooked up it was throwing 24, and remembering that.
Shouldnt be a speed sensor thing because the speed input is hooked up to the same wiring as the digital speedo which is working fine.

[RObErT_RaTh]

The ECU definately keeps codes, because before i had the air temp sensor hooked up it was throwing 24, and remembering that.
Shouldnt be a speed sensor thing because the speed input is hooked up to the same wiring as the digital speedo which is working fine.

Can you remember the last time you drove the car over 80? Is there any roads on the way to upullit that are 80kph? The fact the light turns on spot on as I hit 80 makes me inclined to think there is still something funky going on with this speed sensor business.

[takai]

Given that the only two error codes in this list: http://www.toymods.net/forums/showpo...27&postcount=2 that i can see relating to Speed are 9 and 42 youll have to figure out which one it is.

Most of the time i was driving it was <60 due to it being Adelaide, and on the 80 roads i tended to sit in 5th which was around 17-1800rpm.

[WA_TRD_83]

so the Check Engine light comes on and then stays on until you turn the car off?
what RPM are you doin by the time you hit 80kms?

[CrUZida]

Shouldnt be a speed sensor thing because the speed input is hooked up to the same wiring as the digital speedo which is working fine.

I can't say for the JZA80, but most other Toyota's of that era don't use the speedo input signal for SPD, they use the speedo output signal.

I know some of the newer ones are different, but I don't know where the change over is.

[RObErT_RaTh]

Takai, cheers for the link

"42 Vehicle Speed Sensor No speed sensor signal to ECU when loaded driving condition with engine speeds 2000 to 5000 rpm. for 8 seconds or more.
VSS
ECU"

Could be this as I think I would've been accelerating in the 70 zone in 3rd or 4th and then changed to 5th once I was at 80. Extended higher engine speed to get to 80 up the hill sounds like it fits the bill for triggering the light.

so the Check Engine light comes on and then stays on until you turn the car off?
what RPM are you doin by the time you hit 80kms?

Yeah, I can't say I kept driving for more than 5 mins after the times it has happened. Didn't know what it was so didn't want to kill the car so pulled over and turned it off. Was gone when I started again. Can't be exact on the revs, and no 80k roads close by that I know of but might be able to try it again on the weekend and take exact note what revs I was at, or I can just rev less and see if it comes on or not too.

I can't say for the JZA80, but most other Toyota's of that era don't use the speedo input signal for SPD, they use the speedo output signal.

I know some of the newer ones are different, but I don't know where the change over is.

Ah so I need to feed it a speedo output signal then? Just a matter of finding out where this comes from (or making it come from somewhere) and hook it up and it shouldn't do it again? Would be nice if this is an easy fix