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Engine Specific Info and Questions => IDI Engine => Topic started by: Mopar44o on June 02, 2008, 03:12:49 pm

Title: Rough with A/C on
Post by: Mopar44o on June 02, 2008, 03:12:49 pm
Hi guys, New to VW's and Diesel here.

Just got a 96 vw jetta gl diesel. Runs great except when ac is on.

It blows ice cold and when cruising at 2000+ rpms no problems

The problems are when the ac is on and I take it out of gear the rpms drop really low and it almost stalls out (stalled once). Or when trying to get rolling from a stop I gotta rev the *** out of it and it idles low and rough.

Other than when the ac is on though I have none of these problems. Anyone know what the cause is and how to fix it?

Thanks
V
Title: Rough with A/C on
Post by: gigaz2 on June 02, 2008, 03:24:55 pm
what engine do you have?
Title: Rough with A/C on
Post by: Mopar44o on June 02, 2008, 03:26:19 pm
Its a turbo diesel So im guessing in 96 its the 1.9 no?
Title: Rough with A/C on
Post by: gigaz2 on June 02, 2008, 03:30:10 pm
it helps when we know what engine you have under the bonnet ;)
Title: Rough with A/C on
Post by: Mopar44o on June 02, 2008, 03:42:43 pm
Well please correct me if I'm wrong but they only had one turbo diesel option in 1996 no? The 1.9L right? So that would pretty much narrow it down

And we call it a hood over here ;)
Title: Rough with A/C on
Post by: Vincent Waldon on June 02, 2008, 03:42:50 pm
Quote from: "Mopar44o"
Its a turbo diesel So im guessing in 96 its the 1.9 no?


Unless you've had an engine swap you have the AAZ version of the engine... and it should have a fast-idle actuator that bumps up the idle when the A/C clutch comes on.

It's a black plastic device on the top of the injection pump with vacuum connections to a solenoid valve.... it has a cable that pulls on an IP lever.  Sounds like yours is defective/missing.
Title: Rough with A/C on
Post by: Vincent Waldon on June 02, 2008, 03:44:07 pm
Quote from: "Mopar44o"
Well please correct me if I'm wrong but they only had one turbo diesel option in 1996 no? The 1.9L right? So that would pretty much narrow it down

And we call it a hood over here ;)


This is an international forum... you would do well to respect the fact that there are many different people here from many different countries... not all of whom call it a hood.  :wink:

This also means that what actual engine you have *is* a relevant question.... not only did VW ship many different engine configurations worldwide but many folks have done engine swaps.
Title: Rough with A/C on
Post by: Mopar44o on June 02, 2008, 03:52:23 pm
I was just joking with the hood comment no harm meant. Sorry buddy if you were offended it wasn't the intention.

Im pretty sure I know what you're talking about with the actuator is their a way to test it or adjust it?
Title: Rough with A/C on
Post by: gigaz2 on June 02, 2008, 04:11:31 pm
no prob on my behalf ;)

you can apply vacuum directly to the canister, it should move and make the idle go higher in order to cope with the AC load.
Title: Rough with A/C on
Post by: RabbitJockey on June 02, 2008, 05:05:10 pm
in america they call it a mushroom and in the europe they call it an elephant trunk
Title: Rough with A/C on
Post by: Mopar44o on June 02, 2008, 06:14:16 pm
It  looks like there are several hoses coming off the acutuator which one is the vacuum line that is responsible for pulling the cable?
Title: Rough with A/C on
Post by: Vincent Waldon on June 02, 2008, 07:11:14 pm
Quote from: "Mopar44o"
no harm meant.



Me neither... I myself get "toque" and "hat" mixed up all the time. And then there's "haggis" and  "food poisoning"  ;-)

All of the AAZ fast-idle actuators I've seen only have one hose connection:

(http://i197.photobucket.com/albums/aa85/vwaldon/AAZ_AC_idle.jpg)

On mine that one hose leads to a solenoid valve mounted on the passenger-side shock tower.  From the solenoid valve another hose goes to the a tee fitting on the vacuum pump.

Sound familiar, or perhaps yours is a different configuration ??
Title: Rough with A/C on
Post by: Mopar44o on June 02, 2008, 07:46:30 pm
Heres photos of mine i snapped now.

(http://i13.photobucket.com/albums/a265/440Charger/100_0670.jpg)

(http://i13.photobucket.com/albums/a265/440Charger/100_0671.jpg)

(http://i13.photobucket.com/albums/a265/440Charger/100_0672.jpg)

Looks a little differnt from yours[/img]
Title: Rough with A/C on
Post by: Vincent Waldon on June 02, 2008, 07:58:19 pm
(http://i197.photobucket.com/albums/aa85/vwaldon/other_AAZ.jpg)
Title: Rough with A/C on
Post by: Mopar44o on June 02, 2008, 08:00:00 pm
That thingy is my improvised fuel line that replaced the one that cracked twice :D the line to the #2 injector crack twice on me. Thats a gm 6.3 L diesel line straightend out and bent to "fit"
Title: Rough with A/C on
Post by: Mopar44o on June 02, 2008, 08:01:30 pm
Oh wait nm I see what you're pointing to... Its late here :D

There is one that runs along the injectors then goes down below the intake tube. I loose it after that. Plus its dark here. Doesn't seem like there is a spot for a second hose to connect to that.
Title: Rough with A/C on
Post by: Vincent Waldon on June 02, 2008, 08:55:26 pm
Actually I mean the black canister behind the interesting fuel line. ;-)
Title: Rough with A/C on
Post by: Vincent Waldon on June 02, 2008, 08:57:36 pm
yup, so that's the actuator.. apply suction to the hose that goes into it and it should tug on a lever and up the idle.

If not... it's defective.

If so... then the issue is upstream... follow that hose, I'll bet it goes to the white plastic line you can see in the other picture by the air filter, and then to the solenoid valve.
Title: Rough with A/C on
Post by: jtanguay on June 02, 2008, 09:18:03 pm
the rubber can sometimes rot and then provide a leak.  this would probably result in loss of vacuum somewhat... maybe even less power brakes???
Title: Rough with A/C on
Post by: Mopar44o on June 04, 2008, 06:07:43 pm
So I checked it today. Used a vacuum pump on it and no go. The line is sucking pretty hard to. So I guess its the actuator.

Is it hard to replace? Do I have to replace the whole assembly or just the the part where the line hooks up to?

Whats the part run for?
Title: Rough with A/C on
Post by: Mopar44o on June 05, 2008, 10:17:35 pm
Bump
Title: Rough with A/C on
Post by: Mopar44o on June 06, 2008, 02:58:44 pm
Figured out why the idle doesn't rise

Looked at it closely and noticed that it worked in many ways similar to a carburetor... So it stopped looking so Greek to me


On the end of the cable that pulls the lever there is supposed to be a nut or clamp of some sort. Mines missing. So the cable is completely loose... Now I gotta figure out a way to clamp the cable snug.
Title: Rough with A/C on
Post by: Mopar44o on June 07, 2008, 01:12:39 pm
Thank god crappy tire sells some of those cable clamps.

After clamping the cable The idle with a/c improved right away. Then I had to adjust the idle for a/c and non a/c to get it from stalling out when taking it out of gear. But now it works good.

Thanks Vincent Waldon for that picture. It helped.
Title: Rough with A/C on
Post by: Vincent Waldon on June 07, 2008, 02:10:39 pm
Quote from: "Mopar44o"
Thank god crappy tire sells some of those cable clamps.

After clamping the cable The idle with a/c improved right away. Then I had to adjust the idle for a/c and non a/c to get it from stalling out when taking it out of gear. But now it works good.

Thanks Vincent Waldon for that picture. It helped.


No prob dude... a picture is worth at least 1000 words, as they say !!