Notices
MEGAsquirt A place to collectively sort out this megasquirt gizmo

another prob with the NB

Old Jan 18, 2009 | 11:49 PM
  #1  
what miata?'s Avatar
Thread Starter
Junior Member
 
Joined: Nov 2006
Posts: 158
Total Cats: 0
Default another prob with the NB

Man im sorry for all the threads but this NB is kicking my ***. After i sorted out the issue with the CAS i got the car started. The issue im having with the car is it wont hold afr's correctly. first time seeing this, Ive install MS on a few NA with out a prob. Im guessing something is wrong with the fuel system on the car or something. I load my msq file from my daily( NA, turbo, 550cc ect ) expecting to have the car drivable and it runs like crap. So i figure i will adjust.. i make adjustments to the table its fine for a second then goes too lean or rich depending on what i did. This prob has been going on for a while with other management in the car. The owner had exede on it before and said he could never get it to run right no matter what he did to the fuel table. The car still has the EGR system still in would that effect anything? Also never messed with a return less fuel system, do you think that would have to do anything with it?
The injectors are 550 and they fresh and checked.

Im lost if anyone has suggestions shoot im all ears
Old Jan 19, 2009 | 12:01 AM
  #2  
patsmx5's Avatar
Elite Member
iTrader: (16)
 
Joined: Aug 2007
Posts: 9,406
Total Cats: 559
From: Houston, TX
Default

Originally Posted by what miata?
Man im sorry for all the threads but this NB is kicking my ***. After i sorted out the issue with the CAS i got the car started. The issue im having with the car is it wont hold afr's correctly. first time seeing this, Ive install MS on a few NA with out a prob. Im guessing something is wrong with the fuel system on the car or something. I load my msq file from my daily( NA, turbo, 550cc ect ) expecting to have the car drivable and it runs like crap. So i figure i will adjust.. i make adjustments to the table its fine for a second then goes too lean or rich depending on what i did. This prob has been going on for a while with other management in the car. The owner had exede on it before and said he could never get it to run right no matter what he did to the fuel table. The car still has the EGR system still in would that effect anything? Also never messed with a return less fuel system, do you think that would have to do anything with it?
The injectors are 550 and they fresh and checked.

Im lost if anyone has suggestions shoot im all ears
Post the msq that you're running on the nb and I'll have a look. You can attach it.

Does it run fair? Driveable? Do AFR's ever get stable? What kind of AFRs are you getting?
Old Jan 19, 2009 | 01:09 AM
  #3  
what miata?'s Avatar
Thread Starter
Junior Member
 
Joined: Nov 2006
Posts: 158
Total Cats: 0
Default

Ill log it tomorrow when i go to work and post it. Its hardly drivable. one min its at a good afr when adjusted. Then afr goes to **** with the same valued just entered..
Attached Files
File Type: msq
1-3-09 street 6-7lbshighres.msq (35.2 KB, 161 views)
Old Jan 19, 2009 | 11:40 AM
  #4  
patsmx5's Avatar
Elite Member
iTrader: (16)
 
Joined: Aug 2007
Posts: 9,406
Total Cats: 559
From: Houston, TX
Default

msq looks good. I'd double check the ignition input circuit settings as I'm not familiar with those. You mention it had fuel problems before installing MS. That's probably the problem. Again, a datalog will help. Yall have the map line hooked up, right? Also you could answer the questions I already asked. Might help.
Old Jan 19, 2009 | 01:01 PM
  #5  
what miata?'s Avatar
Thread Starter
Junior Member
 
Joined: Nov 2006
Posts: 158
Total Cats: 0
Default

Here is the log from this morning drive to work.

When looking at it i tried to keep a steady kpa on the highway and you see the afr's change with the same load. The duty cycle has not change also.

There are two things that im thinking

1- That im getting irregular fuel pressure (returnless system)
2- EGR malfunction and exhaust gases interrupting with tune

but im leaning more with the first one.....
any ideas?
Attached Files
File Type: xls
datalog200801242147.xls (898.0 KB, 132 views)
Old Jan 19, 2009 | 01:16 PM
  #6  
patsmx5's Avatar
Elite Member
iTrader: (16)
 
Joined: Aug 2007
Posts: 9,406
Total Cats: 559
From: Houston, TX
Default

Could be a dying fuel pump. But you do have other problems. You have a lot of noise. The CLT reading is all bouncy. So is the TPS signal. The TPS signal being noisy will cause TPS based acceleration enrichments to come on. Try turning those off and see if it gets better. You still have to figure out what's causing the noise and fix it though.

Where is the vacuum line hooked to on the intake manifold? What size vac line?
How is everything wired up?
What wideband and how's it wired up?
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
TonyV
General Miata Chat
75
Mar 27, 2012 06:45 PM
mtncrvr
General Miata Chat
30
Jun 30, 2008 10:17 PM
miataz
Miata parts for sale/trade
3
Dec 10, 2007 09:18 PM
IcantDo55
Insert BS here
8
Nov 7, 2007 04:44 PM


Thread Tools
Search this Thread

All times are GMT -4. The time now is 08:35 AM.