June 24, 2018, 02:12:12 AM

Author Topic: Poor Acceleration from a stop / DDEC I II III IV / smoke control / Fix ??  (Read 13286 times)

Offline homermandy

  • Jr. Member
  • **
  • Posts: 85
Forgot to mention that on my Pro-Link, there is an option which shows Smoke Control YES/NO(I think option 31). Anyways, it shows NO on the ProLink.  I would have thought it would be set to Yes. 
1991 Eagle 15

Offline RTS/Daytona

  • Hero Member
  • *****
  • Posts: 526
  • Pete RTS/Daytona ->'89 TMC 35' 102" 6V92TA 4:10
    • BUS CONVERSION PARTS FOR SALE / PROJECTS
homermandy

Thanks for the followup - hmmm don't understand your PRO-LINK "no boost" reading with the 100 ohm - when Bill did the testing his Pro-Link showed a few pounds boost ??

Glad the 100 ohm still works for you - received another report yesterday - 100 ohm worked great for a Blitz re-built RTS ddec II 6V92TA

Pete

I don't understand D/D "smoke Control" option - I'm confused - but we appear to have a good "work around" - the 100 Ohm resistor wired between the Turbo Sensor pin "C" and "B"
If you ain't part of the solution, then you're part of the problem.

Offline homermandy

  • Jr. Member
  • **
  • Posts: 85
Took another spin tonight. Had the prolink hooked up to monitor boost while driving.  Interesting, the boost registered on the prolink was half of the boost registered on my guage.  I can pull about 20psi at full boost.  However the prolink never got over about half.  Now someone else had a similar(maybe not similar) issue where the ECM read full boost then fell to zero. His problem was fuel starvation if I remember correctly. Anyways, it makes me intrigued.  I didn't measure boost without the resistor yet, but I would believe it would have no effect in the upper boost range. Anyone else seen this?  I doubt my guage is wrong......
1991 Eagle 15

Offline homermandy

  • Jr. Member
  • **
  • Posts: 85
I suppose on the troubleshooting side, 1st I should make sure I have 1volt at pinB for zero boost.  If that does not register correct voltage, sensor may be broken. AND, it could be possible I have a small enough leak in the hose from the blower to the sensor causing the low voltage. But I would think if voltage measures around 1V at idle, sensor probably is ok. 
1991 Eagle 15

Offline RTS/Daytona

  • Hero Member
  • *****
  • Posts: 526
  • Pete RTS/Daytona ->'89 TMC 35' 102" 6V92TA 4:10
    • BUS CONVERSION PARTS FOR SALE / PROJECTS
homermandy

Hmmm - I think you need to remove the resistor and hookup the prolink and take it for another ride - just to eliminate any false readings due to the resistor

But I don't believe that the resistor has any effect at full boost

Pete RTS/Daytona
If you ain't part of the solution, then you're part of the problem.

Offline homermandy

  • Jr. Member
  • **
  • Posts: 85
Ok, so I got more ambitious. Without the resistor, lead c measures 5V, lead B measures 1V.  Prolink registers 0psi.
With the resistor, 5V at C, almost 2V at B, and still 0psi at Prolink. Won't be able to take for a spin until tomorrow evening.
Also put 5V directly to B and a fault registered on Prolink. hmmmmm
1991 Eagle 15

Offline RTS/Daytona

  • Hero Member
  • *****
  • Posts: 526
  • Pete RTS/Daytona ->'89 TMC 35' 102" 6V92TA 4:10
    • BUS CONVERSION PARTS FOR SALE / PROJECTS
pin B - operating range - approx .5v to 4.75 - voltages outside this range will cause a DDEC Fault
If you ain't part of the solution, then you're part of the problem.

Offline homermandy

  • Jr. Member
  • **
  • Posts: 85
Ok, so I think we may not understand how the DDEC program works. I had a potentiometer wired for about 50ohms between b and c pins. Checked voltage was about 3 volts or so. When yu turn on the ignition, it takes a while for the prolink to initialize. But i quickly scrolled down to boost PSI and it was dropping to zero(soonest I could get the display scrolled it was about 5psi). So I believe the prolink is getting the correct psi reading, but I believe it uses other parameters also. Not sure why it would not stay on what would be like 10psi? But it definately dropped to zero.  hmmmm.
1991 Eagle 15

Offline homermandy

  • Jr. Member
  • **
  • Posts: 85
Here is the link to the similar boost behavior....

http://www.busnut.com/bbs/messages/233/10261.html
1991 Eagle 15

Offline Rich (Prevost)

  • Jr. Member
  • **
  • Posts: 77
Neat stuff Pete.............Keep me posted.

Rich
800-468-5287