Dubsquad.org

78 Rabbit, CIS, 1.6L

Facts:
*Doesn't "do it" when it's cold.
*Seems to "do it" when under load most (going up a hill etc).
*Sputters a small bit while at idle, there is a 'hic during idle that is rhythmic.
*WOT leads to TONS of hesitation but car does eventually accelerate.
*Is worse at times but less at others.

What I've done thus far that's probably not related:
*Replaced fuzebox.
*Replaced sparkplugs.
*Replaced wires.
*Replaced cap/roter.
*Replaced oil.

What i've done in trying to fix this or like issues:
*Replaced primary fuel filter.
*Replaced fuel pump.
*Replaced thermal timing switch.
*Replaced injectors/seals.
*Replaced warmup regulator.
*Replaced Air Filter.
*Cleaned Fuel distributor.
*Replaced all available vacuum lines and everything is now hooked up!
*Timed the vehicle.

...about the only thing I haven't done is the EGR.  Duff mentioned it might be a mix issue on the fuel distributor?  Fuck, I've always been scared shitless to play with the mixes on there. 

Does anyone have any ideas?  I've quite seriously built this car from the ground up and would so hate to have to bring it into a mechanics shop to ask for help :(

From just reading the title, here's my advice. Just talk to her dude, it's only a broad, the worst thing that will happen is she says "no."

Hahah, thanks!  Good advice, but I think I'm going to stick with slipping GHB in her coke and waiting till she's asleep like I usually do.

condoms, candy, flowers, ghb = things u take on a date

did u check tming? both the cam timing and igniton? i had a rabbit last week a good 2teeth off behaving like this, reset cam timing and wow it was magilcy better

CIS meter air boot and TB boot?

did you check the contact points?

I haven't changed the cam timing, do you think that it could just "meander out"?  The car wasn't doing this issue a couple months ago.


I suppose that's a possibility.  They look good but leaks could be anywhere.  I have spares so will swap those over.


I didn't cause I replaced them when I started work on the car, who knows, I'll check em again!

Thanks a bunch for the responses guys!!!  My adventures into "non-carb'd land" have been treacherous!

So they're new?  Not likely the problem, but sounds to me like a vacuum leak somewhere.  Have you chased for leaks with either a propane bottle of brake clean?

The contact points?  Replaced.  The boots?  They aren't new but they are much newER and look it externally. 

I got this post to my same query on the whoretex:


It's pretty much GOT to be a vacuum leak at this point as I've replaced/fixed most everything having to do with fuel.  The rationale sounds sound.  I'm going to swap the boot first then think about deleting my EGR and check the auxillary air regulator...

Um...cold start valves ONLY spray during startup (ie cranking), they don't do anything else any other time but hang out. 

I was talking about the intake and TB boots, I've had perfectly good looking ones cause issues.  Especially cause you say it acts up depending on if the motor is loaded (engine torquing, pulling on the boots)

Roger that, I'm a FI newby :).


That's what I figured you were talkin' about.  That's a quick fix, I'll swap those when I get home and see how it goes.

Timing - Mine behaved identically and even though I was damn certain I had timed it right, I had the crank retarded two teeth from everything else.

Alternately, check your cold-start air bypass valve. I had one that had cracked in half at the seam and would sometimes suck itself back together. Caused an intermittent version of what you're describing. I always remove them and plug both hoses after that experience.

Swapped the boots and EGR, problem persists but is less.  I found a gaping hole behind the boot at the TB so I'm sure that was part of it.  Car doesn't lurch as hard now - it's just a super bad sputter that doesn't allow me to accelerate or run right still - when warm (which is super frustrating since the car runs LIKE A FUCKING DREAM when it's cold).

Perhaps it is Timing.  I must admit - I don't fully understand how to be a tooth out.  You mean on the flywheel/I'm going to have to pull the trans again, rotate the flywheel a couple teeth and reinstall?

No, the flywheel is keyed into place by means of offset bolts.  The tooth off is refering to the timing belt.  I'd double check the timing.

So now it only stutters when warm?  I think you said you already changed the warm up regulator in the fuel system?  That's an odd one.

Alright, that makes more sense.  I did change the warm up regulator.  Yep, only when warm, man it's frustrating.  I'll hit it again with the timing light and then try to make sure it's not a tooth off (Bentley here I come).

BTW - it was a RIDICULOUSLY awesome night last night for riding the bike  :thumbsup:

Nobody up here runs the CPR, so I can't say I've seen what problems with those would do. I have heard of them going bad and doing a variety of weird things, though.

If it's only doing it when it's warm, it's probably not timing.

Travis, I have just about every CIS diagnostic tool available.  :wave:

Does your car run well enough to drive over?


 

Actually yea, I could make it over.  When are you available?  PS - I love you.

now, I'm jealous!  :wave:

I had a great time at Dannys, there was meat exchanged  :dance:

Moose burger BBQ planned for Friday...  :thumbsup:

where can i get my hand on some meat.......... love me some moose burgers

LC, you know I am your one stop meat dispensory, now, just arrive, close your eyes, open your mouth, here comes a surprise!

So what the hell was the problem?

Dannys is always fun, I have to admit.

While at Dannys we swapped the fuel dist after dinking with all the timings...  Then played with the air/fuel mix.  Got rid of the hesitation issue all together.  Still sputters.  We think it's due to a vacuum leak at the intake and possible an issue with the CPR.  I'll be switchin them both here very soon...

Update.

Swapped intake manifold, throttle body, new TB and intake gasket, new battery connector on the + side, new fuel injector cups...

Problem persists.  I'm giving up.  I'm going to take it to a shop on Tuesday.

Did you check around for vacuum leaks with a can  of carb/brake cleaner?  It's worth a try for $4.

oh yes it is!  when it revs, you've found the spot!!  :dance:

We did, the only indicator it gave was that the car changed rpms when we sprayed on top of the front of the intake manifold, right over the injectors.  Bugger is they are new o-rings.  This is why I replaced the intake manifold/gasket and the new injector cups.  I haven't tried it again since swapping all of that.  I spose I should.

Behavior of the problem has changed after all of this.  The problem now is a constant sputter, hot or cold.  I seem to have full speed of the car and almost full acceleration.  Just the damned constant sputter.

This weekend I'll probably do the timing belt, tensioner and shift linkage (5 speed box etc) and when I have money, bring the bitch in.

How did you set your A/F ratio?
Just in case, simple way to do it is to unplug the O2 sensor and plug a voltmeter into it, wait for the car to warm up, then adjust your A/F so it reads as close to .5 volts as possible. If it starts jumping around all weird and shit, you still have vacuum leaks but if it stabilizes you're golden. That's if you're running a single-wire O2 sensor. Even if it starts jumping around a lot, it's a sign that your ECU and associated bits are doing what they're supposed to and you just need to do some housecleaning in the vacuum department.

trav, are you sure its fuel infection issues?

you might be having an ignition problem, especially if its constant...

I had a problem starting the scirocco recently, expected the worst... it ended up being fouled plugs.

There is no O2 sensor on this guy.  Danny tuned the A/F for the FD on a car that had an O2 and verified that it was accurate.  As far as vacuum policing - I've replaced 100% of the lines with new lines and Danny and I did quite a bit of the spray/idle check and only found variance near the injectors - which after that I replaced the intake and gasket and then injector seals and cups.


I'm really not sure.  I was at such a loss I finally just brought it into waldenburg performance here local to a good friend.  Man, I swear I about swapped everything in the engine bay.  Plugs was one of the first things I checked, new wires etc but honestly didn't check anything else ignition wise.  I spose that was a mistake.

I would have probably sprayed the wires with water to see if they arced at all, but sometimes they can have internal resistance issues that can cause the same problem without being externally fucked up..

hopefully its something cheap... good luck!

Did this ever get fixed? I'm curious to know how it turned out.

Well, I got the car back from waldenburg and the car ran better then it ever has...  I asked Jay wtf they did and he said not much - usual small stuff.  Then the car just started to work...  He seems to think the problem was with the plug wires (the gap being to great from plug to wire internally).  I had it converted over to the MK2 stylee and he converted it back and the problem seemed to vanish for the most part - the car still sputters and loses power at high rpms but I dunno.  Works fine as long as you don't take it above 3500 rpms but that's pretty annoying.

I'm suspect of the head really.  I have a 2L that will be going in the car and I'm currently driving my new diesel so - I just drove it as it was and gave up....

Bummer. I just got another rocco and it's got some serious idle/vacuum issues that I get to work on this weekend.

how many is that now for you? 36?

Sciroccos? I'm down to 2. Sold one to brother-in-law, gave up the Callaway to a friend who was in love with it... Now it's just the 79 (which I might also give away) and this red 85, which technically belongs to my fiancee, since it was her speakers that I traded for it.

The Corrado ruined my collection. It ate all the time and money that would have gone towards tweaking on the 53's.

corrados ruin everything.

part it out.