solved? was: [16v] hard start, bucking/bogging off idle

[scirocco at vintagewatercooleds.com (Eric S)]

Don, your getting two systems confused.  (not your fault)

CIS-E (16vs) you do need a little harness so you can intercept the
readings going to the DPR.

CIS Lambda (8v with oxy sensor) has a small 2 prong connector near the
rain tray for measuring the signals going to the Frequency Valve. (similar
in function to a DPR on CIS-E).  You need a dwell meter for that reading
though.

-- 
Eric
www.vintagewatercooleds.com

1981 Scirocco S (TDI swap project)
1988 Audi 90 Quattro
1990 Corrado TDI
1991 Cabriolet (2.0 crossflow 8v project)

Don Walter said:
> Did you use a special harness to check with the ammeter?  That is how
> I have always thought it had to be done but just recently another
> scirocco owner said he could check it by using the open connector that
> is near the firewall (used for testing) to measure the Air/Fuel ratio.
>  Anyone else hear that?  Should would beat having to hook up that
> harness or leaving it in and jumpering it.
>
>
>
> On Sun, 5 Dec 2004 19:12:00 -0800 (PST), T. Reed <treed2@wsu.edu> wrote:
>> My car really pissed me off today.. it did the "cut out in the middle of
>> busy intersection" thing, then it ran like crap all the way back home. I
>> felt like I should drive it really hard to teach it a lesson, but it
>> would
>> just buck and slow down whenever I hit the gas.
>>
>> So... despite 28 F, darkness, several inches of snow deposited on
>> several
>> inches of ice, and a 10 mph wind, I decided I was going to go out and
>> find
>> out what the hell was making it do this.
>>
>> Popped the hood, began looking around. Discovered that the coolant
>> temperature sensor wire insulation was cracked and the wire had bent at
>> a
>> 90 degree angle because of the lost strength. It was all nasty and
>> corroded. Decided that it would be good to replace, so I got my
>> inverter,
>> soldering iron, and a desk lamp (had to improvise since I'm away from
>> all
>> my tools), and soldered a new tail on the wire. Only after reconnecting
>> it did it occur to me that this was the sensor for the GAUGE!! Ugh, I
>> need
>> to work on my car as often as I used to so I'll start thinking these
>> things through...
>>
>> The one for the F.I. has an interlocking 2 wire connector. Oh well, I
>> guess having accurate engine temps in the cluster is important too.
>>
>> Frustrated but numb from the cold, I realized it had been a while since
>> I
>> checked/set the dpr current at idle. I think it was April or May.. so I
>> hooked up the ammeter, dpr harness, and got my 3mm hex key.
>>
>> Checked the current. It was something like 17 mA, then 15 mA, then 10
>> mA,
>> then 6 mA, then 2 mA, then 17 mA, and it kept repeating this cycle. The
>> low battery indicator was flashing on the meter so I replaced it and
>> tried
>> again. This time I got a steady 5-6-5-4-5-6-5-4-5-6-5-4 fluctuation.
>>
>> Decided to try setting it to the stock 10 mA +/- 1 mA. After doing so,
>> unhooked everything and went for a spin.
>>
>> Wow, lots of low end torque now. I could spin the tires (on snow/ice of
>> course) in 1st through 4th just by giving it a little gas. The car feels
>> distinctly different, so I proceed out of the parking lot with caution.
>> Drove around the neighborhood, stopping about 10 times... no problems
>> with
>> stalling or bucking when coming off idle! Now my biggest problem is
>> throwing snow in 1st or 2nd even if I start out easy..
>>
>> Did I fix it? I hope so! I won't know for sure until it doesn't do it
>> for
>> like a week straight..
>>
>> The current theory is.. some things have changed since I last set the
>> dpr
>> current:
>> - the cat plugged up and had to be gutted to put it out of its misery
>> - added an autotech fuel module (disconnected for past few days)
>> - new battery cables and grounds
>> - car sat for 3 months
>> - the temperature dropped (20 - 30 F  vs.  45 - 65 F)
>>
>> Somehow, these factors made the idle mixture rich enough to cause the
>> car
>> to run like crap.
>>
>> Cold enrichment would make an already rich motor richer, which could
>> explain why this problem didn't set in until after I put the snow tires
>> on
>> (it's been consistently 10 - 15 F colder since I put them on). The
>> sudden
>> disappearance of the cat could throw things out of tune too
>> (particularly
>> if I last set the dpr current when the cat was still semi-plugged).
>>
>> The other corroborating evidence is that despite bucking and bogging
>> seemingly at random, the car ran amazing above about 3500 rpm.. all
>> kinds
>> of torque. It ran right up to the rev limiter..
>>
>> So apparently this craptacular hesitation is what a 2L 16V with CIS-E
>> will
>> do when there is proper fueling at the top end, but too much fuel around
>> idle.
>>
>> Now, with the 10 +/- 1 mA current setting, its going to peter out at
>> 5000
>> rpm or so, but be very strong down low..
>>
>> Anyway, just thought I'd share the latest development in my quest to
>> make
>> this damn car run properly.
>>
>> -Toby
>>
>> _______________________________________________
>> Scirocco-l mailing list
>> Scirocco-l@scirocco.org
>> http://neubayern.net/mailman/listinfo/scirocco-l
>>
>
>
> --
> Don Walter - Waukesha, WI
> 1986 1.8 16V Black Scirocco
> 1986 2L 16V Toronado Red Scirocco (under repair)
> 1988 1.8 16V Toronado Red Scirocco (sold on 3/29/04)
> 1984 1.8 8V Pewter Scirocco (sold years ago)
> 1971 Karman Ghia (sold)
> 1969 Karman Ghia (sold)
> 1969 Beetle (sold)
>
> _______________________________________________
> Scirocco-l mailing list
> Scirocco-l@scirocco.org
> http://neubayern.net/mailman/listinfo/scirocco-l
>