My car used to have a intermittent bad connection at the differential pressure regulator if I recall correctly. It would act sluggish until I wiggled the connectors on the side of the air intake and restarted the engine. I think the ignition key off/on resets something in the computer. The coolant temp sensor circuit also plays a role in the air fuel ratio so I'd check those out.
On Tue, Oct 19, 2010 at 12:54 PM, Matthew Yip <[email protected]> wrote: > I changed the knock box but have the same issues. I'm starting to think > that it's a weak O2 sensor. > > Here's my logic which is probably flawed. > > The O2 sensor has a heater - when I start the car from cold, it fires up > easily due to the cold-start valve. Perhaps 30 seconds after cold-start, the > engine stumbles and is very sluggish to respond to the throttle. It remains > sluggish until the engine temp warms up which keeps in thinking that the O2 > sensor is bad. > > The problem is worse when it rains which points to a bad ground as well but > I'm at a loss about where to find that issue. > > Aarrgggghhh!!! Maybe I should knuckle under and buy a car built in this > century. > > - Matthew - > > On Oct 1, 2010, at 21:16, Denis Goldman <[email protected]> wrote: > > > Matt, > > > > I had that same intermittent power-loss/limp-home/acts-as-no-o2-sensor is > > connected gremlin at one point - turned out, after months of trial and > > error, swapping parts one at a time, to be the knock box under the > passenger > > side of the windshield (this was a CIS-E 1.8 16v, I think motronic has > the > > 02/Knock CPU as part of the main CPU on the driver's side). > > > > The key cycle you mentioned was the same for me....unlike a torn air > boot, > > the problem often went away with a quick flip of the ignition. > > > > Swap it out with a good one if you have access to someone with an > extra... > > > > Of course, if you have motronic, then disregard what I said above. :) > > > > Regards, > > Denis > > > > On Fri, Oct 1, 2010 at 12:27 PM, Matthew Yip <[email protected]> wrote: > > > >> ITA allows for a final-drive change but it's verbotten to "mix and > match" > >> the > >> internals. I run a 4.25 which, according to Shine, is the wrong final > >> drive - > >> wrong for his application but fine for me. > >> > >> > >> I've considered a newer car and the myriad of benefits. The issue is > that > >> I'm > >> flush with antique VW bits - most of which are worthless to anyone who > >> isn't an > >> "enthusiast". That having been said, I'd love to get into an E30 BMW > >> (newer but > >> not so new that it's fully computer controlled) or an Integra (new > enough > >> to be > >> tunable). > >> > >> > >> > >> My street 16v GTi seems to have a black cloud hovering over it - I've > >> touched > >> virtually EVERYTHING and yet it spites me. It starts and runs GREAT > until > >> it > >> drops into some sort of low-power mode, sputtering and stumbling. All I > >> have to > >> do is cycle the key and it goes away BUT I have no idea where to start. > It > >> drops into that mode for no apparent reason and all temperatures > although > >> it's > >> more "sensitive" when it's cool and wet. AAARRRGGGHHH!!! Give me > >> something > >> broken - I abhor these intermittent problems. > >> > >> Matthew > >> > >> > >> > >> ----- Original Message ---- > >>> From: Les Noriel <[email protected]> > >>> To: Volkswagen a2 16v discussion list <[email protected]>; > >>> [email protected] > >>> Sent: Fri, October 1, 2010 11:21:39 AM > >>> Subject: Re: [a2-16v-list] General Li Update > >>> > >>> Matthew, > >>> Does ITA allow for any gearing changes or do they have to remain > stock? > >>> > >>> Over revving the motor--Many of the newer cars once again have engine > >>> management limitations that prevent that from occurring on newer > engines. > >>> Again, another advantage to newer cars. > >>> > >>> > >>> Regarding older cars, Rafi Kazanjian of Eurosport campaigns a MK1 here > >> on the > >>> West Coast. The car is almost entirely stock. The balance and > lightweight > >> of > >>> the car (Along with his driving skills) makes him competitive against > >> many of > >>> the newer cars. > >>> > >>> > >>> I had a similar electrical experience on the road with my MKI many > years > >> ago. > >>> It did not matter what I did, the wire would dislodge from the > >> alternatior. I > >>> replaced the cable, used zip ties, etc. I even created a small metal > >> bracket > >>> and screwed it down to prevent the cable from coming off. That was to > no > >> avail > >>> as the metal bracket broke one day while driving away from a stop > light. > >> That > >>> car was cursed and refused to be fixed. > >>> > >>> > >>> Good luck this season. > >>> -----Original Message----- > >>>> From: Matthew Yip <[email protected]> > >>>> Sent: Oct 1, 2010 6:46 AM > >>>> To: [email protected] > >>>> Subject: [a2-16v-list] General Li Update > >>>> > >>>> It's been several years since I've written any updates. I'm > astonished > >> that > >>>> y'all find my drivel interesting. Be honest - many of you have kids > now > >> and > >>> need > >>> > >>>> > >>>> something to read that will drone the kiddies to sleep. > >>>> > >>>> > >>>> > >>>> Nothing too spectacular has happened in the past 3-4 years of racing. > >> The car > >>> is > >>> > >>>> > >>>> becoming less competitive bc of new cars being classed into ITA. I'm > >> not > >>> pleased > >>> > >>>> > >>>> but understand that we can't stand in the way of progress. What I am > >> seeing > >>> that > >>> > >>>> > >>>> annoys me is that the EFI cars are getting all the breaks while the > old > >> junk > >> > >>>> like the CIS-E or carbureted cars are getting left behind. > >>>> > >>>> > >>>> After 6, yes SIX, seasons, I finally replaced the otherwise stock > >> engine 3 > >>> years > >>> > >>>> > >>>> ago. The "race" motor is now a .020 overviews 1.8l 16v with porting > as > >>> allowed > >>> > >>>> in IT - 1" in from the outside edge of the head. Otherwise everything > >> else is > >>> > >>>> OE, just fresh and new. > >>>> > >>>> > >>>> > >>>> The results of the fresh engine amazing. All that time spent trying > to > >> eke > >>> out > >>> > >>>> momentum paid off. The engine was worth a good second PLUS it as > great > >> to > >>> final > >>> > >>>> motor past other cars on the straights. > >>>> > >>>> > >>>> 2 years ago, I finally ditched my ancient Koni single adjustable for > >> some > >>>> Bilstein Race shocks. Again, what a HUGE difference. The car actually > >> stuck > >>> and > >>> > >>>> I found myself gaining in otherwise faster cars in the twisties. > >>>> > >>>> > >>>> The past years have had a few "moments" as well. > >>>> > >>>> The last race of 2007, a car spun on the first lap in T9. I spun to > >> avoid or > >>> I'd > >>> > >>>> > >>>> have shortened his car by several feet. I took out the tyre wall with > >> the LF > >>> but > >>> > >>>> > >>>> the car was unfazed. Unfortunately, going down the front straight, I > >> saw a > >>> flash > >>> > >>>> > >>>> of orange which told me that the hood pin had come loose. Worse, > >> entering T3, > >>> > >>>> the car go loose on me, I jumped the inside kerbing, giving the car > >> behind > >>> me, > >>> > >>>> the SAME that that I'd spun to avoid, a great view of the underside > of > >> the > >>>> General Li as I balanced the car on the RR tyre. I slid to a stop in > a > >> cloud > >>> of > >>> > >>>> > >>>> dust, heard squealing tyres and WHAM - Earl's 240 pummeled the > driver's > >> side > >>> of > >>> > >>>> my car, side-to-side. I restarted my car and left the scene in a > hurry > >> to > >>> avoid > >>> > >>>> > >>>> having other cars find me in the fog. Ducking into the pits, I > >> frantically > >>>> motioned to some friends (I still don't normally travel with crew) to > >> take a > >> > >>>> look at the hood - they gave me a "Come back in 2 laps" signal. 2 > laps > >>> later, I > >>> > >>>> > >>>> > >>>> returned and they graciously taped my hood shut and I returned to the > >> melee. > >>> > >>>> > >>>> The final outcome wasn't pretty but it wasn't hopeless either. The > >> drivers' > >> > >>>> side of the car was beat up and the rocker panel was bent at the > >> trailing > >>> edge > >>> > >>>> of the door BUT the car was still running without any pulling, > rubbing > >> or > >>> fluid > >>> > >>>> leaks. Earl's 240 went back to the paddock b/c of a bent tie rod - > >> Germany > >>> 2, > >>> > >>>> Japan 0. > >>>> > >>>> Over the winter, I replaced the fender and Auto Expectations (owned > by > >> the > >>>> former owners of Datsun Dynamics) pulled the major dents in the LR > >> quarter > >>>> panel. I retained the door and the dents in the rocker panel for > >> asthetics. > >>> > >>>> > >>>> > >>>> For the first race of 2008, we raced in a misty pseudo-rain. A few > >> laps into > >>> > >>>> the race, I was running with Doug's MR2 and eating up the track. In > T7 > >> on > >>>> Summit Point, Doug started a rather lurid spin - anticipating that > he'd > >> spin > >>> off > >>> > >>>> > >>>> to driver's right, I hit the grass on driver's left. Nope - wrong > idea > >> - > >>> Doug's > >>> > >>>> > >>>> car instead came back to driver's left and found the RF of my car. I > >> tagged > >>> the > >>> > >>>> > >>>> RR of his MR2, spinning both of us surprisingly quickly. Per usual, > I > >> drove > >> > >>>> away, bouncing off the rev limiter in the grass. Doug got the short > >> end of > >>> that > >>> > >>>> > >>>> contact with about 6 degrees of toe-out in the RR - Germany 3, Japan > 0. > >>>> > >>>> > >>>> > >>>> The rest of 2008 went well with some oddities starting show up as the > >> car > >>> ages. > >>> > >>>> > >>>> > >>>> > >>>> In particular was an infuriating miss during hard right turns - this > is > >>>> indicative of fuel starvation so I started adding more and more fuel > to > >> the > >>>> car. The problem persisted and I started wondering if something in > the > >> fuel > >> > >>>> system was starting to fail - I HATE intermittent problems with a > >> passion. > >>> Then > >>> > >>>> > >>>> Brian, my crew and now fellow competitor (or maybe it was Bob, one of > >> my > >>> other > >>> > >>>> crew and Brian's Dad) who noticed that the main electrical connection > to > >> the > >> > >>>> alternator was broken. The tab was completely broken away BUT > because > >> of > >>>> metal-memory, it touched the connector. However, under hard right > >> turns, the > >>> > >>>> connector was "pulled" away from the alternator - since the voltage > was > >>> marginal > >>> > >>>> > >>>> (thought the alternator was just junk), the car WAS cutting out in > hard > >> right > >>> > >>>> turns but it was electrical, NOT fuel. Ugh - problem solved although > >> we > >>>> encountered the same problem in 2009. At least we'd seen it before > and > >> Bob, > >> > >>>> whom we all refer to as the Mad Scientist (Think Dexter of Dexter's > >>> Laboratory) > >>> > >>>> was prepared with a full electrical kit including lugs specifically > >> sized for > >>> > >>>> the alternator. > >>>> > >>>> > >>>> As a whole, 2008 was an exercise in frustration - the car is just as > >> fast as > >>> it > >>> > >>>> was in the past 1:31-1:30 on Summit Point Main but the new cars are > >> getting > >>>> significantly faster. The lap record on SP Main is now in the 1:26 > >> range > >>> (might > >>> > >>>> > >>>> even be in the 1.25s - I try to put that out of my mind or I'm just > >>> depressed). > >>> > >>>> > >>>> Starts are still my favorites, especially charging down the middle, > >> scaring > >>> the > >>> > >>>> daylights out of the smaller cars. At the end of 2008, Ryan, my > other > >> crew > >>> and > >>> > >>>> soon-to-be Brian's brother-in-law, thanked me for not making him do > >> bodywork > >> > >>>> over the winter - that's gratitude for you...<G> > >>>> > >>>> In Fall 2008, Brian, my crew member, decided to go racing and I > offered > >> him > >>> the > >>> > >>>> General Li for School. He took to the car like a duck to water which > >> was bad > >>> > >>>> for me. Actually it was amusing to watch the car going around the > >> track > >>> without > >>> > >>>> > >>>> me driving. Some of my fellow competitors mentioned that the car > >> looked fast > >>> - > >>> > >>>> probably b/c it was at least 50 lbs lighter without me driving. I > >> reminded > >>> all > >>> > >>>> > >>>> of them that my bumpers are both big and strong. During the race and > >> the end > >>> of > >>> > >>>> > >>>> Driver's School, Brian and Jesse, son of one of my ITA competitors, > >> were > >>> running > >>> > >>>> > >>>> inches apart. As they came thru T10, we only saw the General Li - > poor > >> Todd, > >>> > >>>> Jesse's Dad exclaimed "Oh, no - Jesse must have gone off". About the > >> same > >>> time > >>> > >>>> that he said that, Jesse popped out from behind the General Li and > >> suddenly, > >> > >>>> there were 2 cars...very, very cool. > >>>> > >>>> 2009 was another exercise in frustration - Brian's car wasn't > completed > >> so we > >>> > >>>> shared the General Li during the season. At the first race, we had > >> shifter > >>>> problems and ended up changing the clutch. That wasn't the problem > and > >> at > >>> VIR, > >>> > >>>> the issues just got worse as the trans had no interest in finding > >> gears. > >>> This > >>> > >>>> made for interesting racing since gear changes had to be very slow and > >>>> deliberate. This relegated me towards the back of the pack and made > >> racing > >>> more > >>> > >>>> > >>>> of a chore than a fun competition. When we (actually just me) > returned > >> from > >> > >>>> VIR, we (this time ALL of us) pulled the trans and sent it to a buddy > >> who is > >>> a > >>> > >>>> VW Master Tech and a transaxle guru. The verdict was that the 1-2 > >> slide had > >> > >>>> worn along with a clutch disc that delaminated - something about an > >> over-rev > >>> on > >>> > >>>> downshift - couldn't have been me <G>. > >>>> > >>>> Once the trans was fixed, the light at the end of the tunnel started > >> getting > >> > >>>> brighter although racing a now "vintage" VW has many challenges. > >> During one > >> > >>>> race, whilst racing with a pack of cars, the car just shut off - the > >> coil > >>> wire > >>> > >>>> popped off - something that happened many years ago so we zip-tied > the > >> wire > >>> in > >>> > >>>> place - apparently that wasn't enough. Scratch one DNF into the > books. > >>>> > >>>> Updates for 2010 to follow shortly. > >>>> > >>>> - Matthew - > >>>> > >>>> > >>>> > >>>> _______________________________________________ > >>>> a2-16v-list mailing list > >>>> [email protected] > >>>> http://mail.a2-16v.com/mailman/listinfo/a2-16v-list > >>>> For list archives, see listinfo link above. > >>> > >>> > >>> > >>> _______________________________________________ > >>> a2-16v-list mailing list > >>> [email protected] > >>> http://mail.a2-16v.com/mailman/listinfo/a2-16v-list > >>> For list archives, see listinfo link above. > >>> > >> > >> > >> > >> _______________________________________________ > >> a2-16v-list mailing list > >> [email protected] > >> http://mail.a2-16v.com/mailman/listinfo/a2-16v-list > >> For list archives, see listinfo link above. > >> > > _______________________________________________ > > a2-16v-list mailing list > > [email protected] > > http://mail.a2-16v.com/mailman/listinfo/a2-16v-list > > For list archives, see listinfo link above. > > _______________________________________________ > a2-16v-list mailing list > [email protected] > http://mail.a2-16v.com/mailman/listinfo/a2-16v-list > For list archives, see listinfo link above. >
