motorgeek.com :: Socially inappropriate motoring information.
Search this topic:
motorgeek.com :: Board index :: 034 Motorsport :: 034 EFI
Post new topic Reply to topic  [ 3 posts ] 

Help with stuttering/suging diagnosis at part throttle

Author Message
 Post subject: Help with stuttering/suging diagnosis at part throttle
PostPosted: Mon Sep 05, 2016 5:23 pm 
Offline
Redline?

Joined: Wed Jul 27, 2005 1:36 pm
Posts: 110
Location: Maine
Haven't posted in ages, but in the last year or so, my VW 2l 16v running IB w/stock distributor has developed an increasing case of part throttle surging and/or bucking. I've been running the same tune for probably close to 10 years so my thoughts are that's not the issue. If anyone has any thoughts on what it may be (or how to diagnose), I would appreciate it.

Some pertinent info:
-Seems to be getting worse over time.
-It's the worst at part throttle steady cruise (~3000rpm)
-Recently changed plugs, plug wires, distribution cap and rotor with no change.
-Not running any kind of Idle air controller
-There is no way it's a plugged cat
-Not running any o2 input
-I have a fuel pressure gauge in the car and it remains constant through the surging
-I'm lucky if I make it through 1 tank of gas a year, although last year I did fill it up twice, and that seemed to make no difference

thanks for the help
(and just saw no more 034 :? :x )


Top
 Profile  
Reply with quote  
 Post subject: Re: Help with stuttering/suging diagnosis at part throttle
PostPosted: Wed Sep 07, 2016 12:50 pm 
Offline
kickin' tires'n lightin fires
User avatar

Joined: Fri Sep 03, 2004 8:06 pm
Posts: 943
Location: Woodland hills (Los Angeles) CA.
could be two things, bad ign. driver or you're getting interference in the cable/connections for the timing wheel VR sensor pickup. These VR pickups have a very low output and are susceptible to picking up noise in the cable. You should be able to see it on the real time monitor page, look at the hall sensor on the dist: "#cam"
and the VR pickup "WDbg"


Image

_________________
http://picasaweb.google.com/type85

Image

Image


Top
 Profile  
Reply with quote  
 Post subject: Re: Help with stuttering/suging diagnosis at part throttle
PostPosted: Wed Sep 07, 2016 6:59 pm 
Offline
I sprinkle rubber on my Cherios
User avatar

Joined: Tue Sep 29, 2009 6:59 pm
Posts: 260
Location: Bellingham, WA,98225
My first guess was Hall sensor as it commonly shows issues at 2500-3000. I have no experience with 1B, so just guessing. If your stock distributor has a hall unit, check it out. DDG sounds like he's got your system and know's it, so good advice, listen to him....
I live in a very similar climate and a boat owner, and there's 2 schools of thought on gas tanks....you are either a "keep it totally full to limit condensation" or a "keep it empty with fuel treatment, so you can burn out the bad easily"....Since the boat's got a water separating fuel filter, I go empty and change it yearly. Boat's got a 120 gallon tank, so last thing I need is 120 gallons of less than fresh gas. Has worked for me for 20 yrs. The 5-speed sat for the last 3 yrs, and I left 5 treated gallons in it, and is running fine after putting 3 gallons of premium and running that thru....If your filter is old, might want to replace that just for fun. If I"m gonna drive it all winter, I'll keep it more full than empty(needs a few things that I was going to get to this summer, but havent, so it's got 1/4 tank).......Ha

_________________
90 V8 Lago Blue 113K(nice)
93 V8 Pearl 205K(Sold)
91 V8 Indigo pearl 5-speed 165K(Love)
90 V8 Titan Grey 125K (parted)
91 V8 Indigo Pearl (parted)
91 V8 Panther Black 198K(sold)
90 V8 Panther Black 218K(sold)
04 Silverado 2500 HD 4x4(forever)
87 Silver Saab Turbo 205K(given away to friend for project)
4 other Saabs that I'm starting to miss.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 3 posts ] 
Search this topic:
motorgeek.com :: Board index :: 034 Motorsport :: 034 EFI

Jump to:  



Information

Users browsing this forum: No registered users and 2 guests



You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum
  |  It is currently Tue Jan 24, 2017 10:09 am
Share |