Very high RPM after start with ms3 & ms3x
09-12-2016, 01:50 PM
#1
Newb
Thread Starter
Join Date: Mar 2016
Posts: 8
Total Cats: 0
Very high RPM after start with ms3 & ms3x
Hey hairdressers,
Just finished building my MS3 with MS3x for my mk2 1.6 mx-5 with Frank's guide. It starts but runs on very high rpm and very lean (19 afr). I tried lowering the VE table to 35 in the idle zone, but it doesn't seem to help. I am new to this whole ecu tuning scene and I'm learning it pretty fast, but I don't know what to do at the moment. The idle valve works and I tried disconnecting it to see if it's the problem, but it didn't matter at all. I couldn't find a basetune for my car, so I just got myself a 1.8 basetune and changed the injector and engine size.
Wideband is connected as a narrowband at the moment because I'm switching the ecu every time cause I need to daily the car. Once the car will be idling normally, I will resolder it.
I included my log and tune, please point me in the right direction
.
Just finished building my MS3 with MS3x for my mk2 1.6 mx-5 with Frank's guide. It starts but runs on very high rpm and very lean (19 afr). I tried lowering the VE table to 35 in the idle zone, but it doesn't seem to help. I am new to this whole ecu tuning scene and I'm learning it pretty fast, but I don't know what to do at the moment. The idle valve works and I tried disconnecting it to see if it's the problem, but it didn't matter at all. I couldn't find a basetune for my car, so I just got myself a 1.8 basetune and changed the injector and engine size.
Wideband is connected as a narrowband at the moment because I'm switching the ecu every time cause I need to daily the car. Once the car will be idling normally, I will resolder it.
I included my log and tune, please point me in the right direction
.
Last edited by Alex Naoumov; 09-20-2016 at 09:56 AM.
Reply
0
0
09-12-2016, 02:00 PM
#2
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
if youre lean, why would you reduce fuel?
what basetune? Im sure it's not a good one.
you certain you dont have a vacuum leak on your IM? I dont see how youre hit >4000RPM on the idle valve alone -- especially with those idle pwm% numbers (assuming you did the flyback mod to the expander card correctly).
what basetune? Im sure it's not a good one.
you certain you dont have a vacuum leak on your IM? I dont see how youre hit >4000RPM on the idle valve alone -- especially with those idle pwm% numbers (assuming you did the flyback mod to the expander card correctly).
Reply
1
1
09-12-2016, 02:19 PM
#3
Newb
Thread Starter
Join Date: Mar 2016
Posts: 8
Total Cats: 0
Thanks for your reply !
That's stupid yeah, didn't really think about that...
I can't upload the basetune right now cause I'm on the cellphone, you can see the tune I'm using in my first post.
Car runs fine on stock ecu with a bolt in the vacuum tube to block it, so I doubt there is a leak in the manifold. I didn't install the flyback diode because somebody told me that it is build in the Ms3x already.. Do you think I need to install iit
!That's stupid yeah, didn't really think about that...
I can't upload the basetune right now cause I'm on the cellphone, you can see the tune I'm using in my first post.
Car runs fine on stock ecu with a bolt in the vacuum tube to block it, so I doubt there is a leak in the manifold. I didn't install the flyback diode because somebody told me that it is build in the Ms3x already.. Do you think I need to install iit
Reply
0
0
09-12-2016, 04:48 PM
#5
Newb
Thread Starter
Join Date: Mar 2016
Posts: 8
Total Cats: 0
Yes, I did. I also tested all my outputs with a scope and they all work. Do you think I still need to install that flyback diode? Even if the expander has one built in?
Actually I had some trouble with this part:
I measured around 2.3-2.4v at both points and turning the resistors didn't change much. Tbh I don't think this is the problem.
I didn't check for a vacuum leak, but I only removed the charcoal canister and put my vacuumline on that port that came free and the vacuumline is good and not leaking.
Actually I had some trouble with this part:
Step 2: fine adjustment of the VR circuits:
– For the main board, measure the voltage on the upper leg of R54 while turning R56.
– For the MS3X board, measure the voltage on the lower leg of R17 (close to U7) while turning R11.
In both cases, you want to see about 2.5 to 3 volts at that point, which puts you right in the middle of the actual output range of the sensors.
– For the main board, measure the voltage on the upper leg of R54 while turning R56.
– For the MS3X board, measure the voltage on the lower leg of R17 (close to U7) while turning R11.
In both cases, you want to see about 2.5 to 3 volts at that point, which puts you right in the middle of the actual output range of the sensors.
I didn't check for a vacuum leak, but I only removed the charcoal canister and put my vacuumline on that port that came free and the vacuumline is good and not leaking.
Reply
0
0
09-13-2016, 06:59 AM
#6
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
no you do not still need the diode.
VR pots would only matter if your issue was losing cam sync.
use output test mode and fool with the idle duty % and see where the range of operation is.
VR pots would only matter if your issue was losing cam sync.
use output test mode and fool with the idle duty % and see where the range of operation is.
Reply
1
1
09-13-2016, 06:59 AM
#7
Boost Czar
iTrader: (62)
Join Date: May 2005
Location: Chantilly, VA
Posts: 79,493
Total Cats: 4,080
no you do not still need the diode.
VR pots would only matter if your issue was losing cam sync.
use output test mode and fool with the idle duty % and see where the range of operation is.
VR pots would only matter if your issue was losing cam sync.
use output test mode and fool with the idle duty % and see where the range of operation is.
Reply
0
0
Thread
Thread Starter
Forum
Replies
Last Post
