CEL went on after hard acceleration

[xm 1]

so i was driving this morning to my office and had a yellow goin red traffic light in front of me....so i accelerated pretty hard to jut make it. all of the sudden i noticed the the caution sign on the gauge cluster went on and also the CEL !?!?!?! i was like wtf....i couldn't turn around or park the car for next 1 km or so and drove the car normaly.
after about 500 or 800 meters both of the lights went out!! the car behaved as normal during all of this.i tried again to push the car a bit "harder" than you normally do and i revd it till 4k in 3rd gear and again both lights came on and went out after 1 min. (or even less). so i tried it to drive the car normal till i could make a halt. again i accelerated till 3k this time and again both light came on and went out. still had to drive the car for about 5km or so and tried it once more but nothing happened!!
to find the cause for this is pretty hard without nowing the car or check it of course, but what could have caused this problem? can i read out the CEL if the light went out again? not sure about that.
i may have already an idea of what it could be but i'm not sure....so here's my guess:
if the oxygen sensor detects a "leak" during hard acceleration but not under normal driving condition because the exhaust is soaking somewhere air in...what that cause the lights to go on and go out if you drive the car normally because the leak than is sealed again????
because it only happened when i was letting the gas pedal go to shift into the next gear!!
i have a universal hks silencer fitted to a already exsited Invidia cat back....the inner silencer on the hks has some gap around the tail pipe like 3-4 mm!!!!!! so it's not sitting pretty well and it's vibrating in idle....could it be that after all the exhaust gas is flowing out of the tail while accelerating and than let the gas go to shift there is some air sucked in trough this little gap and causes the O2 sensor to get a wrong reading??

[Mr Ree NZ]

Do a diagnostic to avoid any guess work.

Also, check your brake fluid level and oil level

[xm 1]

just wanted to know if there's a error message stored even if the cel goes out.....because normally it stays on if there's a problem....or????

[Mr Ree NZ]

The light normally stays on until you turn the key off, but the error will store in the acu, hence why I suggested to check your fluid levels.

But running the diagnostic check is simple and only takes a paperclip and 5 minutes to confirm the issue (or not)

[xm 1]

it´s error code 42 ??? as far as i know it´s the speed sensor ?!?!?!?

[aphlux]

If its manual, do the VSS splice fix to see if that clears your CEL. I would recommend not cutting the harness, but pulling the wire from the plug and then using a vampire bite. Worked for me.

http://www.supraforums.com/forum/sho...+sensor+splice

[Mr Ree NZ]

Is your car a series 1 or 2 chassis?

The splice seems to only help those who have S1 chassis.

Ive done it to mine as I have code 42 and it still appears at the same point everytime I drive.

No harm no foul though

[xm 1]

not sure about the series but it is a 93 Na jdm Sup (so i guess it's a S1 chassis). what could be the problem is that there was a km/h to mph converter spliced/cut into the speed signal....this might be the fault....or it is the TRD tach!?!?
strange is that it just appeared out of no where.....because i drove the car last year after the TRD installation for about 500km and nothing happend. the car was stored for winter and now i have these probs (drove the car for about 180km before the CEL came on).i'll def. have to check the wiring on the speedo i think...which is a pita to take out the entire dash.....AGAIN

[xm 1]

maybe one thing i have forgotten to tell!!!! .....my right warning light pod was faulty!!! i had no CEL or other ligths on...so i figured out that it was the plug which connected the display with the car harness. i fixed it and now i have all lights lit up again.....could i've done something wrong here?? maybe causing a short somewhere??? but than there shouldn't come up a code 42....or???

[Mr Ree NZ]

It will more than likely have something to do with the mph/kph converter as anything that is wired into the circuit seems to cause it to get upset.

The VSS fault is very commong, but I would simply try the splice fix first and see how you get on.

[xm 1]

will def. try this....as for the converter...i unpluged it and rewired all the cables, maybe there's the problem?? just another question shouldn't on a km odo stand km?? because i only have the milage or km on it!?!

[xm 1]

so it seems like the problem was a easy fix!! (hopefully) i removed the dash trim and found some cable connections oxidized.....fixed this and since that time i had no CEL coming on!!

[xm 1]

not fixed still get from time to time the CEL for speed sensor!!!!!! still not sure how to fix (just an update for people with the same problem)

[Mr Ree NZ]

I think that short of replacing every single part, inluding wiring, it will never be solved.

Dry solder joints are very often the reason in S1 chassis, but less so in S2. Go figure...

[xm 1]

it might be a bad odo.....took it apart and a part just fell off after i touched it resoldered it and hoped for the best but i think the odo is so f++ked up i have to either buy a new one or get a good used one. the pre-owner even cut a connection on the display thing so that the KM sign was out all the time (i think he did this because he had the converter from km to mph in the car).well......it's pretty strange it takes some time after i reset the CEL to come on again!?!?!? after i reseted the CEL i drove twice about 100 km and nothing happend!!! i think the CEL comes on at around 75-80 km/h noticed this because i had to drive 70 for a long period and all of the sudden the CEL went on and after i accelerated a bit (up to 85-90 km/h) the CEL went out !!!!
f""k electric problems

[Mr Ree NZ]

It happens when the ECU knows there is a sustained load for 8 seconds or more at a certain rpm point.

Normally happens on my car when im going onto the motorway and sitting between 80 and 100 kph, or always without fail, when im holding the same speed while going up a hill.