BK stumble, stutter, shudder I have Vag-com

artie b

Veteran Member
Joined
Sep 23, 2001
Location
zip code 46371
TDI
97 B4 TDI stock, have owned and repaired 4 B4 TDI's since 1996
Morning everyone. I have been very fortunate that I have never had to use my Vag-com for anything other than timing on a TB change and resetting the IQ after a IP reseal.
I have a BK ECM. 5th injector and cat probes are resistor ed out. EGR wires only. Timing at top of graph, and a IQ of 7 warm.
No codes.
When I accerate slow, like I do, a slight hesitation, then a small surge.
When I up shift early, like I do, a shudder presents itself.
Starts nice warm hot and cold. No smoking, pulls nice, boost jumps to 15 psi or so, then settles down smoothly.
I have searched and found that my practice of taking the timing to the moon, is not ideal, must be complemented with a good IQ starting point.
I'll be checking my injector balance, and gather whatever information we need to get it running smoothly.
I'm comfortable with whatever needs to be done. Such as hammer mod or adaptation with help.
Thanks to everyone Artie
 

Abacus

That helpful B4 guy
Joined
Nov 10, 2007
Location
Relocated from Maine to Dewey, AZ
TDI
Only the B4V left
Drop the IQ to 3.5+/- and see if it goes away. An IQ of 7 is pretty high unless you're running PP520's or larger injectors, and even then it's at the upper end of where I'd run the PP520's. I assume your fuel filter is clear? Have you done an Italian Tune Up lately to clean things out? Slow acceleration and early shifting will coke these cars up pretty good in short order. I've had to de-coke more than one to clean it out and the owner is always surprised at what comes out the tailpipe and how much better it runs after. I recommend them once a week to once a month depending on use.
 
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artie b

Veteran Member
Joined
Sep 23, 2001
Location
zip code 46371
TDI
97 B4 TDI stock, have owned and repaired 4 B4 TDI's since 1996
Thanks Abucus, this is an engine, ecm, donor for my GLX wagon swap, I got from Goodmonkey. I'll contact him and ask on some history. I was hoping to hold off on a water pump until the TB was due...... pump has another agenda, Fix me now! Thanks again Abucus.
I'll get a hold of Goodmonkey and go from there.
 

artie b

Veteran Member
Joined
Sep 23, 2001
Location
zip code 46371
TDI
97 B4 TDI stock, have owned and repaired 4 B4 TDI's since 1996
Hi and I did the water pump and checked TB timing, right on. All seals are dry. When I checked my IQ it was 5. Before when I had the 7, the AC was on. Ah, I said. More quantity to maintain an idle with a load.
When I drove it there was still a stumdle of an idle when in first gear. When i have my aux fuel pump on it seems to go away. I'll address the feul filter and my tanks draw straw, and go from there. As the pick up is a gas unit that had the in tank pump removed.
Thanks Artie
 
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