VEMS Startup - Rennlist - Porsche Discussion Forums

Notices

VEMS Startup

 
Old 02-24-2018, 07:10 PM
  #1  
David Ewell
Addict
Rennlist Member
Thread Starter
 
Join Date: May 2014
Location: South Jordan, Utah
Posts: 81
Default VEMS Startup

Just reaching out to anyone who might have gone down this road I'm currently on with initial startup issues after installing VEMS ECU. I have been working closely with Peeps and he has tried his best to help me diagnose a no spark no fuel condition during cranking. My car is an 86' 951 with a new 3.1l which was running with M-Tune, but had a few issues with WOT hesitation and a sharp idle drop an deceleration so I decided to go another direction. With all the options stand alone offered I decided to go with VEMS to have more versatility when it came to tuning. This is my first exposure to tuning/operating a stand alone ecu and Peeps has showed a lot of patience with me. So where we're at today is, Verified 500-1000 ohms from speed and reference sensors at the sensor and at the VEMS ecu connector. Verified the wasted spark setup thru a test mode within VEMS to each spark plug and its correct location. Fuel pump is priming when key is on. Made a trigger log and sent it off to Peeps for evaluation, but have not heard back yet on the results. I've been talking with another RL on here about my situation and he had asked if I was running a light weight FW. I have a Spec 3 push clutch with the steel FW that has the 3 scallops to reduce the rotating mass. I know from reading other threads on here that it has caused some screwy things to happen with the speed and reference sensors with a no spark and no fuel issues or just not running correctly. If anyone has had experience with this please pipe in, it will be greatly appreciated. Other items I've replaced last year are, injector wiring harness, DME relay and during the install of VEMS replaced all the pos & neg battery cables and terminals throughout.

Last edited by David Ewell; 02-24-2018 at 09:12 PM. Reason: adding information
David Ewell is offline  
Old 02-24-2018, 07:29 PM
  #2  
PaulD_944S2
User
 
PaulD_944S2's Avatar
 
Join Date: Jul 2014
Location: SoCal
Posts: 748
Default

Not sure where you are at in trouble shooting, but here is a video showing a static & dynamic test of the flywheel sensors.
I realize that your wiring is going to be different now, but if you've got VEMS installed then you should have some knowledge of the ignition system.

PaulD_944S2 is offline  
Old 02-24-2018, 09:09 PM
  #3  
David Ewell
Addict
Rennlist Member
Thread Starter
 
Join Date: May 2014
Location: South Jordan, Utah
Posts: 81
Default

Thanks Paul, I recall viewing this video a year ago when I was having troubles getting the 3.1l running for the first time.
David Ewell is offline  
Old 02-24-2018, 10:49 PM
  #4  
gpr8er
Addict
Rennlist Member
 
gpr8er's Avatar
 
Join Date: Jun 2008
Location: So. Cal
Posts: 663
Default

Oh man sorry to hear of your trouble David

My vems is currently in route should probably have it in the next week or so.

I have virtually the same setup as you. I was running M tune with basically the same run issues that you outlined. I also decided better to go vems.

My car is alusil 3L. I have a fully lightened stock steel flywheel with the BMW speed and reference sensors.

I assume you've tried the simple stuff like swapping the plugs on the speed and reference sensor?
gpr8er is offline  
Old 02-25-2018, 12:33 PM
  #5  
V2Rocket
Rainman
Rennlist Member
 
V2Rocket's Avatar
 
Join Date: Jan 2007
Location: Rancho Cucamonga, CA
Posts: 42,460
Default

when you turn the key to "on" do you hear the fuel pump priming?
V2Rocket is offline  
Old 02-25-2018, 01:08 PM
  #6  
shortyboy
Addict
Rennlist Member
 
shortyboy's Avatar
 
Join Date: Dec 2002
Location: Honolulu,HI
Posts: 2,311
Default

Do you have factory alarm?
shortyboy is offline  
Old 02-25-2018, 10:44 PM
  #7  
Quickbeam
User
 
Quickbeam's Avatar
 
Join Date: Jun 2002
Location: Reading, PA
Posts: 75
Default

If the car has not run with the spec clutch, it could be the height of the reference pin. Lindsey has a "technical bulletin" about increasing the height of the reference pin and spacing the reference sensor up using a stock speed sensor spacer.

I have had issues with my spec push clutch related to kick back on start up that I have not been able to solve. I have been wondering if vems would solve this. I'll be watching your progress.
Quickbeam is offline  
Old 02-26-2018, 12:14 AM
  #8  
Dave951
User
 
Dave951's Avatar
 
Join Date: Apr 2005
Location: Princeton, NJ
Posts: 833
Default

Originally Posted by Quickbeam View Post
If the car has not run with the spec clutch, it could be the height of the reference pin. Lindsey has a "technical bulletin" about increasing the height of the reference pin and spacing the reference sensor up using a stock speed sensor spacer.
Link to the above mentioned bulletin https://www.lindseyracing.com/LR/Parts/SP44S-FIX.html
Dave951 is offline  
Old 02-26-2018, 12:48 AM
  #9  
Droops83
User
 
Droops83's Avatar
 
Join Date: Feb 2003
Location: Santa Barbara, CA
Posts: 1,180
Default

Originally Posted by Quickbeam View Post
If the car has not run with the spec clutch, it could be the height of the reference pin. Lindsey has a "technical bulletin" about increasing the height of the reference pin and spacing the reference sensor up using a stock speed sensor spacer.

I have had issues with my spec push clutch related to kick back on start up that I have not been able to solve. I have been wondering if vems would solve this. I'll be watching your progress.
Yeah, you really need to scope the speed/reference mark signals and compare them to the waveforms in the factory DME Test Plan manual (available online here recently) before going any further. This is the most fundamental part of your engine management system, and if that is off, nothing is going to be right . . . . .at least check the air gap between the studs and sensors!
Droops83 is offline  
Old 02-26-2018, 06:47 AM
  #10  
ealoken
Addict
Rennlist Member
 
Join Date: Aug 2016
Posts: 883
Default

i had some issues on the EMU setup, what type of sensors have you choosen?
Faling, Hall sensor?
ealoken is offline  
Old 02-26-2018, 01:21 PM
  #11  
David Ewell
Addict
Rennlist Member
Thread Starter
 
Join Date: May 2014
Location: South Jordan, Utah
Posts: 81
Default

Originally Posted by V2Rocket View Post
when you turn the key to "on" do you hear the fuel pump priming?
Yes
David Ewell is offline  
Old 02-26-2018, 01:22 PM
  #12  
David Ewell
Addict
Rennlist Member
Thread Starter
 
Join Date: May 2014
Location: South Jordan, Utah
Posts: 81
Default

Originally Posted by shortyboy View Post
Do you have factory alarm?
No Alarm
David Ewell is offline  
Old 02-26-2018, 01:24 PM
  #13  
David Ewell
Addict
Rennlist Member
Thread Starter
 
Join Date: May 2014
Location: South Jordan, Utah
Posts: 81
Default

Originally Posted by ealoken View Post
i had some issues on the EMU setup, what type of sensors have you choosen?
Faling, Hall sensor?
OEM Senors. Could be the original ones.
David Ewell is offline  
Old 02-26-2018, 01:27 PM
  #14  
ealoken
Addict
Rennlist Member
 
Join Date: Aug 2016
Posts: 883
Default

Originally Posted by David Ewell View Post
OEM Senors. Could be the original ones.
Can you do a osoliscope in wems?
And what sensor have you chose in vems?
ealoken is offline  
Old 02-26-2018, 01:37 PM
  #15  
David Ewell
Addict
Rennlist Member
Thread Starter
 
Join Date: May 2014
Location: South Jordan, Utah
Posts: 81
Default

Originally Posted by Quickbeam View Post
If the car has not run with the spec clutch, it could be the height of the reference pin. Lindsey has a "technical bulletin" about increasing the height of the reference pin and spacing the reference sensor up using a stock speed sensor spacer.

I have had issues with my spec push clutch related to kick back on start up that I have not been able to solve. I have been wondering if vems would solve this. I'll be watching your progress.
Yes, I've been through all of that extensively when starting up the 3.1l for the first time. The problems with startup was not related to the setscrew or the scalloped flywheel. Mainly I discovered shorted out original injector wiring harness plugs.
Peep has messaged me back and has evaluated my trigger log and said it was identical to one he saw previously with a no spark no fuel issue and this case had a spec push clutch with scalloped fw. Peep did not have a solution at the time so the individual installed a separate trigger wheel which fixed his issue. Peep will be looking into it to see if he can find a solution around using a scalloped fw with VEMS.
David Ewell is offline  

Thread Tools
Search this Thread
Quick Reply: VEMS Startup


Contact Us About Us Advertising Cookie Policy Privacy Statement Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: