s2konroids

Hi, hoping some of you guys could 'chime' in (i love that american phrase wink.gif

So im going to revert back to stock kinda fell out of love with my S. I'm going to sell my spoon ECU i proceeded to take it out today and put in the old stock ECU. Remember the spoon ECU requires a ground to earth off pin 15 to chasis (FLR (immboilizer). I have tapped a scotch lock onto that a run an 8inch wire to ground no problems as without it wont startup.

So before installing the old ECU i left the very small tap on but removed the wire (thought if i left the wire it could creat noise/interference), the tap doesnt have any exposed connections.

Car struggled to start did and seemed to be hunting for idle, after a few mins o2 sensor malfunction (p131) and coolant sensor function come on, let it settle switched off the car and reset the CEL light. Started up again no problems took it out for a drive to get it to learn and it seemed to struggle to idle when coming to a stop, rode about for a about 5-10min seemed fine upto 3 bars on temp.

I then tried to vtec then thump! at about 7k rpm, then ran like a bag of shit, o2 sensor CEL light on again, none of the other CEL lights came on (o2 and coolant as above). Struggled to idle again.

Tried again as above but same thing crap running, idling but no CEL when hit wall at 7k rpm.

I'm stumped as to what going on, my thinking is possibly the spoon ECU doesnt monitor the lamda etc (Well o2 sensor, as opposed to the stock ECU putting CEL light on about an o2 sensor), so it could have failed but spoon ecu doesnt care but stock ECU does???

My other thought is maybe this why it runs rich after vtec but this doesnt really show a failure on the dyno as it would have a cack AFR throughout rev range, maybe lower down but i remember 'mase' etc saying spoon ECU is set on side of safety.

However on dyno 3000-6000rpm AFR is about 12.8/9 ish jumps upto about 13.3ish then down at 7k rpm to 12.3 and gradually lower to 12 right at the end at 8200rpm (i ahve 4.57r gears). Dont know if this how the spoon work and sets the AFR? or just because of my mods?(megan header, testpipe, k&n fipk, magnalfow backboxes).

On the dyno is made a genuine increase of 16bhp, better lower down (it would do due to fueling) and around 250bhp.

Im stumped any ideas?

Does any know if the spoon ECU uses all the sensor than stock ECU or uses them differenty?

Thanks in advance

AJ

s2konroids

Also

I do not run a CAT only a testpipe, so i dont think i have damaged that???

Coolant sensor and AIT CEL lights came on only once when i first plugged in the stock ECU, they never came back on.

I also remember when i was stock it wouldnt let me him VTEC when cold but my temp was upto 3 bars and when stock is would hit a brick wall at around 6K RPM.

THe only light that come on again was the p131 when i went to 7k and hit a brick wall the car then ran like a bag of shit frown.gif

ANy other info wecome

negcamber

Here is why I still think your temp sensor is the culpret:

https://www.s2ki.com/forums/index.php?showtopic=690771

If you do a search on "7k" you will get a ton of hits with similar issues all stemming back to the the car being cold or the ecu believing the car is cold.

More than likely your Spoon ECU did not have the feature that lowers fuel cutoff when the car is cold...so it never reported the CEL.

s2konroids

Thanks, i think you could be correct thats seems logical to me.

I have a program that i wrote on my mobile via bleutooth obd2 it reports the lambda osscilating as it should in terms of volts.

s2konroids

Can you clean the temp sensor or is it something you must repalce?

Thanks again appreciate it, hopefully this will solve my problem

negcamber

Replace it.

s2konroids

I read the coolant temperature when running the spoon ECU, the temperature readings seem thing, so i presume if the ECT sensor did need replaced it wouldnt show the correct temp reading???

negcamber

That certainly seems reasonable...however, the spoon ecu didn't give a coolant sensor CEL either, whereas your oem ECU did pick up a fault.

BTW...are you assuming that because the temp gauge was working that the coolant sensor was working fine? The temp gauge on the s2k is not a very accurate gauge...each bar covers a huge range.

s2konroids

The temp is upto 3 bars, but i actually monitor the temperature via a program on my phone, Im tapping into the sensor so i get like 80celcuis etc.

The program bascially communicates via bluetooth ODB2 and reads all the sensors.

I have read the coolant temparature (which i presume gets from the ECT sensor), lamda o2 sensor, CAT o2 sensor, IAT sensor and MAP sensor.

All reporting like they should do without tolerances, for example the coolant is perfectly normal starts off low and more or less stays consistent, i can log these values you see.

negcamber

Sounds like a cool iPhone app.

Anyway...I keep coming back to the original CEL for the ECT. It's the only thing I can think of that would cause the 7k brick wall you describe.

Sorry I couldn't be more help. Hope you can find a solution soon.