45 replies to this topic

[rik]

Just do it and stop asking questions!

[Jase_MK]

To try and put across how much more air the engine gets (the removal of the material allows more air in faster) idle was at 2000rpm until the ecu adjusted it back down to 800rpm.

Bear in mind though that when you disconnect wiring and stuff the ECU resets itself. When my ECU resets and is started up for the first time, it idles at about 2000rpm for a while until it adjusts itself back down to 750.

[p4cks]

When I/we changed my manifold the ECU remained plugged in. Felt no need to unplug it.

[andyroo]

Bear in mind though that when you disconnect wiring and stuff the ECU resets itself. When my ECU resets and is started up for the first time, it idles at about 2000rpm for a while until it adjusts itself back down to 750.

I didnt disconnect the ecu wiring though? And surely the idle is set in the throttle body and is the angle that the butterfly is open by, so the amount it was open to achieve 800rpm before porting was enough for 2000rpm after porting, so the ecu readjusts the butterfly resting position? Not entirely sure what im talking about, but i do know the butterfly isnt closed when you take the tb off, so it must be set for idle?

[Jase_MK]

OK, I assumed you reset the ECU. Probably worth resetting it to be honest so it can learn all the new flow values from scratch with the spangly new TB. I'll take a look at mine when I fit the new manifold, don't want to overdo it though and end up like MarkV...

[andyroo]

OK, I assumed you reset the ECU. Probably worth resetting it to be honest so it can learn all the new flow values from scratch with the spangly new TB.

I'll take a look at mine when I fit the new manifold, don't want to overdo it though and end up like MarkV...

Would that revert to the standard map or stay as the remapped one? I think Markv probably did such a damn good job with it (as he seems to do with everything) that it was too good... Just taking material off the tb and not going near the butterfly shouldnt cause issues, it didnt for me, or anyone else on z22se whos done it!

[Jase_MK]

I wouldn't have thought it would lose the map, no. Otherwise remapped cars would be screwed whenever the battery was disconnected. Someone might want to confirm this though... I'm pretty sure I reset my ECU after having a remap on my last VX and everything was fine.

[john_s]

As I understand, the map is stored in non-volatile memory in an ECU (ie it stays in memory when power is removed). What is lost when resetting / removing the power is the adjustments that the ECU "learns" that it needs to make for optimum running / emission control / etc.

[markv]

As far as I know it usually works like this. The ECU has base maps in its flash memory. When running these maps are copied to RAM and are changed and inter/extrapolated based on driving conditions. When resetting the ECU the working map (with all corrections) is lost and rebuild. When remapping a car you change the base maps in flash memory. Not 100% it is the same with the gmtp-e15, but I think it is. Mark

[andyroo]

Thanks for the info guys Is it good to reset the ecu after doing engine mods then? How would I do that, just by unplugging it?

[Jase_MK]

You can remove fuse 8 for a while (about 45 mins usually does it, no harm in leaving it longer). Open the fuse box, there's two rows of fuses, count down from the windscreen on the outer row (nearer to the wheelarch) until you get to number 8. If you've got the right one, the engine won't start. When you put it back in teh alarm will be armed and start beeping because the bonnet is open so have your keyfob ready. Alternative use an OBD tool to reset the ECU. Will run a bit rough for a the first 20 miles or so and usually takes about a tank of fuel before it's fully back up to speed.

[oakmere]

You can remove fuse 8 for a while (about 45 mins usually does it, no harm in leaving it longer). Open the fuse box, there's two rows of fuses, count down from the windscreen on the outer row (nearer to the wheelarch) until you get to number 8. If you've got the right one, the engine won't start. When you put it back in teh alarm will be armed and start beeping because the bonnet is open so have your keyfob ready.

Alternative use an OBD tool to reset the ECU.

Will run a bit rough for a the first 20 miles or so and usually takes about a tank of fuel before it's fully back up to speed.

Tend to find mine needs much more than 20 miles. After a power cut to the ecu my car runs terrible for the first 20 to 30 miles flat-spots everywhere. I don't think it is fully adjusted until around 300miles are covered may be more.

Is this just my car???

Cheers Oakmere

[Jase_MK]

Is this just my car???

No, that's what I said. Runs rough for the first 20 (you said 20-30) or so miles and takes a full tank before it starts to feel normal, say 200ish, you said 300).

[Zagadka]

Ported and polished my throttle body on sunday (Many thanks for the guide/inspiration Vocky! ) As Andyroo said not sure about power increase but it feels quicker revving and definately 'better'. The weird thing is though it seems to have fixed a little niggle my cars had for a year or so. When it's cold it refuses to accelerate at all , rev's drop and although it's only ever stalled once it feels like it wants to and it's only my judicious and timely clutching that's keeping it running. If you really press on the accelerator nothing , then all the revs arrive at once. I know this sounds awful but it only ever does it for 60 secs to 2 mins. Thats it , then it's ALWAYS fine , so no great problem really. Now as Andyroo described his , one side of my throttle body was black and 'tarry' and it felt to me as though the butterfly was moving just through the surface of this gunk. Post port , although I've only driven her twice so far , it's been perfect even from cold. Is it possible that this deposit is actually affecting the position of the butterfly until it's warmed up enough to become less viscous? Btw EGR as standard ,... at the moment. Kev And before some smart alec comes along - yes , the ladies do like a little timely and judicious clutching

[Anarchy]

Plan to do mine soon, just getting the gear together. Did you do the fuel pressure pipe mod, do you have standard air intake/exhaust?

[techieboy]

Plan to do mine soon, just getting the gear together. Did you do the fuel pressure pipe mod, do you have standard air intake/exhaust?

Think I'm going to tackle my spare TB tomorrow. Got a massive new Dremel kit to use on it and just need to work out which of the 100's of attachments to use. Will do the EGR blanking plate and cheater at the same time. By the state of the interior of the spare TB, recirculating all that exhaust gas is not good.

[EdButler]

I dont suppose anyone has a spare 58mm TB on here that theyre willing to part with or swap for a deposit untill mine is taken off? Id be happy to repeat the favour on to prevent people loosing their daily drivers for a few days

[Anarchy]

Got mine in bits now, the butterfly vane sits at about 30 deg off horizontal and you can push it in each direction. is this 30 deg angle the idle position? Well at this position the vane seems to be sat right at the peak of the worst ridges, your drawing helps a bit but are we meant to not touch the bits when it it is horizontal or at this 30 deg angle? This wont make sense LOL

[Crazyfrog (Fab)]

Got mine in bits now, the butterfly vane sits at about 30 deg off horizontal and you can push it in each direction. is this 30 deg angle the idle position? Well at this position the vane seems to be sat right at the peak of the worst ridges, your drawing helps a bit but are we meant to not touch the bits when it it is horizontal or at this 30 deg angle?

This wont make sense LOL

andyroo did mine and top job the car is transform when i get the 2.4 manifold it will be even better lol

[Anarchy]

I just did the first ridge on the inlet only, the one well out of the way of the vane. Cant say I can tell a difference maybe a bit more popping and noise, not really had a proper go in it though. Was not confident enough to do the others, dont want to mess it up before the National.