Overboost protection

[potatomash]

Hi,

So i have a boost creep issue (we wont talk about that) and I'm not sure if overboost protection is working.

My settings are:
Spark Cut
Max Boost 216.5kpa
Hysteresis 30kpa

In the attached log you can see the RPMs go crazy, as the boost rises, however I cant see any Spark retard going on which worries me.
The highest value on the MAP is 217.2 which also worries me, how can it hit that if it has overboost protection...

Or is this some other weird issue going on?

Thanks.
MS2Extra 3.3.3

[grom_e30]

MSQ??

[potatomash]

The log above shows what I'm talking about

[grom_e30]

but you cant see the settings in side the ecu from the log.

[potatomash]

here it is - I've set it to Both spark and fuel cut since that log however

[grom_e30]

if you look at the log status2 kicks up to 96 that means 32= spark cut and 64= over boost in action, the boost drops to below your hysteresis and the overboost turns off again

see here for status info:

http://www.msextra.com/doc/pdf/html/Meg ... .4-52.html
http://www.msextra.com/doc/pdf/html/Meg ... .4-53.html


edit: its spark cut not retard btw

[potatomash]

Right ok thats cool I didn't know that about status2. However why does the rpm dip first and its not till the second rpm spike the boost cut is kicking in?

How come I still see a map value greater than my boost cut? Is the ecu just not quite fast enough to keep up with the creep or something?

[grom_e30]

not sure about the rpm dips tyres breaking traction maybe or clutch letting go? but you only go above the 216.5 kpa once if you edit that spike out the log you get a max of 214.1 kpa and no boost cut is triggered.

boost cut is not meant to hold the engine. its a fail safe a hard cut to stop things melting if it all goes wrong

[potatomash]

No not breaking traction or clutch, this is top of 3rd gear so its definitely good by then.

I know boost cut is just a fail safe which is all I'm making sure its doing. I've tested it at 10psi and it works as I expect. Its when Im at high rpm its like the hysteresis doesn't drop enough or something odd happening

But that rpm spike is odd, I have looked through the status bits but I don't think it is losing rpm signal is it?

[potatomash]

Check this out, its a tooth log from the same time.

Theres a few pages where the log stops short of the whole page, is this signal loss? Tooth time goes to 0 and Time stays constant..

[grom_e30]

status1 stays at 136 so your all good on the sync count.

the log stopping short is normal, i believe the tooth log is not downloaded in real time i think a few pages are captured then downloaded from the ecu in a chunk, so if the ecu is busy doing something more important than that get priority over the logs.

[potatomash]

Oh really ok then. Well I'm at a loss about why it drops out then..

When it happens its real savage