85 VW manual idles too LOW

Hey, I just got a VW jetta and am learning manual driving. I need to go on a road trip pretty quick, but the beasty doesn't like to start. It idles way below the first mark and if when warming it up you rev it up a little it stalls out...it stalls out any time you seriously slow down or when going slow on a hill. It also does this the first few times you try and move it. Someone said something about a screw I can fiddle with to fix this but I do not know where this is located. I looked at the throttle area and saw no screw or nut that I could turn with ordinary tools. If you can get this to me quickly I would appreciate it...I need to get this thing going.

Reply to
crowscaw
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For this and other questions about your vehicle, get a Bentley service manual.

Reply to
Papa

Assuming you are talking about a US-market vehicle, you could have one of three different engine management systems: K-Jet, KE-Jet, or KE-Jet with knock sensing (only on GLIs). If you have a GLI, you have KE-Jet with knock sensing. Otherwise the easiest thing to do is look at the fuel distributor (on top of the air cleaner box). If its silver/aluminum colored its KE-Jet. If its black then its K-Jet.

The screw you are referring to is most likely the throttle body rest position screw, which is on the side of the throttlebody (on the font left side if you are facedd into the car). However, this is *NOT* an idle adjustment. KE-Jet cars have electronically controlled idle through the idle stabalizer valve. On K-Jet it may be for idle speed control, I don't know K-Jet that well. Do *NOT* adjust this unless you know what you are doing. Get a service manual (Bentley, not Chilton or Haynes)

If it stalls while you depress the throttle, you have another problem besides your idle. That problem may be causing your idle problem, so trying to fix the idle could actually end up making your problem worse.

good luck...

Reply to
blah

I had a friend come check it out and we fiddled with the screw in question and a few other things. (we were careful to count turns) It turns out that most of the problem is my inexperience with standard shift after all. The slight adjustments seemed to help the idle a bit too. Mostly involving lube and checking the conections on a few things. It is still a little cranky, but it doesn't stall out as much. Warming it up for a few minutes helps even out the idle too (at 800-900 RPM). (I still have no idea what motor I have, but the guy who sold it has the bentley manual for me)

Thanks for the suggestions. CC

Reply to
crowscaw

"KE-Jet with knock sensing (only on GLIs)" I am assuming you mean that the US Jetta GLIs (1985-1987) have this system only. Hey what about the Golf GTIs and Golf GTs having the same FI system as the Jettas?

I am th>> Hey, I just got a VW jetta and am learning manual driving. I need to go

Reply to
One out of many daves

First I would try the fuel filter. It will either be located on the air box or under the car by the gas tank.

The screw you are looking for is located in the intake casting itself. Either on the front or the back, right where the throttle mechanisim is located will be a barrel shaped casting about 1/2" in diameter. This will have a slotted screw in it. I doubt that this is your problem though.

Also check the tube from the air box to the intake. The accordian shaped rubbers on either end are notorious for tearing or leaking when they are old. move them and stretch them to look for tears. This tube supplies the vacuum to the fuel management system to regulate the amount of fuel to the motor. Even a small leak will have a big effect.

You can also remove the large rubber boot from the top of the airbox and make sure that the large round flap moves freely.

Checking your air filter might not hurt either.

Here's a number of a VW only parts place in Aubrun Hills (Detroit), MI: (248) 373-2300 . They will have parts for damn near any VW ever made and are well versed in the mechanics area too.

Also here's the address for Bentley:

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can't own an old VW without one of these manuals. Or look on eBay. Igot mine cheap there. Good luck!

Dave

Reply to
ironhorse

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