Notices
Series I Tech Garage The place to discuss anything technical about the RX-8 that doesn't fit into any of the categories below.

I Discovered Why Low Mpg And Low Hp

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 07-23-2005 | 07:51 PM
  #76  
olddragger's Avatar
Registered
iTrader: (3)
 
Joined: Apr 2004
Posts: 10,828
Likes: 38
From: macon, georgia
Thanks Zoom----- we live and learn. As I am not an expert I will take your word for it. So the MAF's are actually closer than what we oridgenally believed?
Actually this ecu is a work of art. Just not to us modders.
Olddragger
Old 07-24-2005 | 08:45 AM
  #77  
Psylence's Avatar
Back in the family
 
Joined: Sep 2003
Posts: 443
Likes: 0
From: philly 'burbs
A work of art indeed.. in that its completely unfathomable except to the original artist

Seriously, someone crack this nut for the good of all RX8 drivers.. please come up with an ECU solution that will still allow me to pass inspection when necesary. First person to do this will have a goldmine on their hands. I don't understand how this car passes emissions what with all the fuel dumping goin' on...
Old 07-24-2005 | 11:09 PM
  #78  
rotarenvy's Avatar
Registered
 
Joined: Feb 2004
Posts: 1,802
Likes: 10
From: QLD .au
from experiance with fitting a haltech to a motor with a motronic style 60-2 trigger wheel the car can run with a number of different wireing configurations for the sensor and angle where it is trigered. in the haltech manual it states something along the lines of 'it wont run quite right' but the difference between right and wrong wasn't detectable to me. so it is possible the ecu will still work with something wrong it will just do things silightly out of sequence.
Old 08-09-2005 | 07:05 PM
  #79  
faffy's Avatar
Registered User
 
Joined: May 2005
Posts: 84
Likes: 0
From: Los Alamos, NM
Has anyone checked what Simo requested? I'd like to know if he was right.

Last edited by faffy; 08-10-2005 at 12:57 AM.
Old 08-09-2005 | 11:13 PM
  #80  
hawgwild's Avatar
NewRX8'r
 
Joined: Mar 2005
Posts: 3
Likes: 1
From: St Louis, MO
Question

Originally Posted by zoom44
here is what is commonly called the trigger wheel for our cars. also known as the e-shaft position plate. remember the 20 brakes stomp reset also resets the eshaft position plate profile in the pcm memory.


Uh, 20 brakes stomp reset???!
Old 08-10-2005 | 03:57 AM
  #81  
Nemesis8's Avatar
Bigus Rotus
iTrader: (3)
 
Joined: Jun 2004
Posts: 8,573
Likes: 1
From: Missouri
And...
Old 08-10-2005 | 05:56 AM
  #82  
Rasputin's Avatar
Registered
 
Joined: Sep 2004
Posts: 581
Likes: 0
From: Europe
The trigger or synchronisation wheel on the Renesis engine is NOT a 60-2 teeth wheel (that's a Bosch standard), but has a more complex pattern : it's a 36 teeth wheel (teeth spaced by 10°) with 6 missing teeth at one place and 3 at another.
The tigger signal coming from the INDUCTIVE (Not Hall effect) sensor (also called Variable Reluctance Sensor) looks like this : TDC - 12 small pulse - wide synch pulse - 15 small pulses - wide synch pulse - wide synch pulse - ... (repeat)

If there was a signal problem, I guess the engine would not synchronise and probably would not start at all!

Source : MAZTECH Mazda Technician Training Manual, October 2003
Old 08-10-2005 | 11:52 AM
  #83  
Hyperborea's Avatar
1 Savior, CTHULU
 
Joined: Jun 2005
Posts: 151
Likes: 0
From: Silicon Valley
Originally Posted by Rasputin
If there was a signal problem, I guess the engine would not synchronise and probably would not start at all!

I write software for a living and have done some embedded software in the past (the ECU is embedded software) so I have some experience with similar systems. A lot of whether it won't start or how bad it would run will depend on the error correction / tolerance that is programmed in. No sensors are 100% perfect so there must be some tolerance for a missing pulse. If there was was no expectation that a missing pulse could occur there would be no need for any synch pulse at all as the ECU could always assume that it's pulse count was 100% accurate.

What we don't know is the error correction just to reset the ECU's computed position when it sees a synch pulse? (i.e. the ECU thinks that it has seen 14 pulses and then the synch pulse comes along and it just goes with that) Or does the ECU keep some sort of count of how often it sees a missed pulse condition and if they occur too often (x missed pulse conditions in y revolutions) it shuts downs or goes into "limp home" mode. Or perhaps it doesn't care about a single missed pulse condition but only if it misses 2 or more pulses in a revolution. We won't know unless we get one of the Mazda software engineers posting here or somebody reverse engineers the ECU (not an easy task).
Old 10-24-2005 | 02:34 PM
  #85  
RotoRocket's Avatar
Freely Radical
iTrader: (1)
 
Joined: Oct 2005
Posts: 1,912
Likes: 9
Originally Posted by Psylence
A 220hp car that gets no better mileage than a Ferrari Modena is just plain wrong .

My 6 speed MT is rated at 238bhp, after the downward adjustment by Mazda (from 250bhp).

Am I correct?
Old 10-24-2005 | 03:08 PM
  #86  
TeamRX8's Avatar
Registered
iTrader: (25)
 
Joined: Apr 2005
Posts: 26,869
Likes: 2,083
do you guys like mustard or mayo on your balonie sandwich?
Old 10-24-2005 | 04:08 PM
  #87  
Red Devil's Avatar
Registered User
 
Joined: Jun 2002
Posts: 3,086
Likes: 1
From: Misinformation Director - Evolv Chicago
This is all interesting. I was hoping someone would come forward having looked into this for Simo.

I average about 17.5 to 18mpg, so I frankly feel little motivation to think about getting my hands dirty.
Old 10-24-2005 | 04:16 PM
  #88  
therm8's Avatar
Bummed, but bring on OU!
 
Joined: Sep 2003
Posts: 2,036
Likes: 1
From: Charleston, SC
Originally Posted by RotoRocket
My 6 speed MT is rated at 238bhp, after the downward adjustment by Mazda (from 250bhp).

Am I correct?
You are correct. Your car is rated at 238bhp.
Old 10-24-2005 | 04:19 PM
  #89  
Rasputin's Avatar
Registered
 
Joined: Sep 2004
Posts: 581
Likes: 0
From: Europe
Originally Posted by zoom44
if it didnt get the signal it was "expecting" it wouldnt run period.
I totally agree. It probably wouln't even start.
Old 10-24-2005 | 09:12 PM
  #90  
Ericok's Avatar
Rotary Wanker
 
Joined: Sep 2005
Posts: 413
Likes: 1
From: Washington, DC
The sensor is located at the bottom front of the engine. Looking at the crankshaft pulley, it's right behind at the 4 o'clock position. Should have a 2 wire connector. It's only held in by one bolt. When looking at the sensor, you should also be able to see the teeth of the trigger wheel (right behind the pulley). Book says the stand alone sensor should read 950-1250 ohms at room temperature.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Shankapotamus3
Series I Trouble Shooting
28
03-14-2021 04:53 PM
Michael Bryant
Series I Wheels, Tires, Brakes & Suspension
5
10-12-2015 04:07 PM
cliffkemp
Series I Trouble Shooting
7
10-04-2015 12:11 AM
MolecularConcept
RX-8 Discussion
11
09-29-2015 10:21 PM
xAgyex
RX-8 Parts For Sale/Wanted
0
09-28-2015 09:54 AM



You have already rated this thread Rating: Thread Rating: 0 votes,  average.


All times are GMT -5. The time now is 07:23 PM.