first project MK2 GL

**luckymois** · 07-25-2012, 12:47 AM

Hey everyone, this is basically my first real post. I just purchased a 91 Jetta GL 1.8L. It needs a bit of work to really get it going. The body is pretty straight, the paint is good, engine seems to run strong and the interior is pretty decent. Currently it does not pass smog but I think that that is probably something minor. I will be posting pics soon, I bought it and had to leave for a few days so I did not have a chance to take any. I am up in Murrieta and it is going to be my daily driver to downtown SD. I mainly purchased it for the great gas mileage, but now that I have it, I remembered how much I loved driving VW's. this will be the 4th that I have ever owned. I am thinking that I want to definately fix it up quite a bit and maybe go with some mild custom.

Any ideas and thoughts will be greatly appreciated. Also my knowledge is kinda on the lacking side so I may ask a lot of questions because of this.

**Euro** · 07-25-2012 12:47 AM

**Agent Orange** · 07-25-2012, 09:33 AM

Ask away. You have to start somewhere. On my first Mk2, I asked a million what seem to be now stupid questions. But 5 Mk2s later, I finally almost have a grasp on it.

Post pics too! The 1.8 8v will never be a rocket, but with some fine tuning and a little love, they can be fun and reliable.

**luckymois** · 07-25-2012, 01:34 PM

i will definately be posting some pics as soon as i get home...

i am mainly wanting it to get slightly better performance...i do not need a lot because i have a heavy foot as is. i just want to tune it and get best mpg possible from it. oh and i need to pass smog before i do anything performance- wise to it.

**g60racer** · 07-26-2012, 09:00 AM

From my years with a 1.8L 8V Jetta Carat (which went 671,000 miles before getting creamed in a wreck), I can tell you that it's a pretty simple motor to keep running well.

To get you up and going and pass smog, do the basics:
*new spark plugs, cap & rotor
*check ignition wires for cracking. Replace them if they're cracked/hardened, not flexible.
*change oil & filter - Mobil1 10W30 or 5W30 works nicely for that motor.
*new air filter (or upgrade to a K&N type cone filter with CARB certification like a Neuspeed P-Flow - won't help performance much but you'll love the noise it makes)
*new O2 sensor
*check for broken vacuum hoses around the intake manifold, replace them as needed. They like to fray & degenerate, and just fall apart.

**luckymois** · 07-26-2012, 12:21 PM

thank you...that is some very helpful advice...just the thing i needed right now. those items will be the first on my list...that and rebuilding the shifter, it is really sloppy and i practically have to slam it into reverse.

are there any plugs that you might recommend as better than others. and should i use synthetic oil(i can't remember if all mobil1 is synth or not)

**luckymois** · 07-26-2012, 01:42 PM

does anyone know of a manual for the 91 jetta that is electronic or pdf format. if so can you hook me up with the link?

**luckymois** · 07-31-2012, 08:21 AM

ok so i have two questions...i went to rock auto's website to order the o2 sensor for my car...how do i know which one is the right one to order. there are like 20 different o2 sensors listed for the 91 jetta gl. i am way confused..

also...i am checking all the vacuum lines and such and coming of the pcv valve hose there is a small blue and white valve in line with the pcv grommet. it has a crack in it...what is it? could this be part of my problem with passing smog?

**rysskii3** · 07-31-2012, 09:49 AM

Originally Posted by luckymois

ok so i have two questions...i went to rock auto's website to order the o2 sensor for my car...how do i know which one is the right one to order. there are like 20 different o2 sensors listed for the 91 jetta gl. i am way confused..

also...i am checking all the vacuum lines and such and coming of the pcv valve hose there is a small blue and white valve in line with the pcv grommet. it has a crack in it...what is it? could this be part of my problem with passing smog?

Check the part number on yours. Or use germanautoparts.com

**Agent Orange** · 07-31-2012, 09:59 AM

Yeah. GAP helps narrow it down a LOT.

**VWaGoGo** · 07-31-2012, 11:21 AM

Originally Posted by luckymois

ok so i have two questions...i went to rock auto's website to order the o2 sensor for my car...how do i know which one is the right one to order. there are like 20 different o2 sensors listed for the 91 jetta gl. i am way confused..

also...i am checking all the vacuum lines and such and coming of the pcv valve hose there is a small blue and white valve in line with the pcv grommet. it has a crack in it...what is it? could this be part of my problem with passing smog?

You can also order parts locally at Pure Motorsports and pick up in the shop to avoid any shipping costs. They can help you out with any questions you may have.

**luckymois** · 07-31-2012, 01:07 PM

thank you for the input on the O@ sensor...that will help a lot..

any ideas on that little plastic blue and white valve in line with the pcv grommet?

**Agent Orange** · 07-31-2012, 01:10 PM

Can you get a pic of it? Sounds like a check valve, but I'm not 100%

**luckymois** · 07-31-2012, 01:25 PM

i am pretty sure it is a check valve also...is there a reason why it is in line with the pcv...does it need to be there or would i be better without it?

**rysskii3** · 07-31-2012, 01:41 PM

Originally Posted by luckymois

i am pretty sure it is a check valve also...is there a reason why it is in line with the pcv...does it need to be there or would i be better without it?

Order everything from Germanautoparts.com! They have about 99% of everything you need to repair your car.

**SYNYSTAGLI** · 07-31-2012, 03:30 PM

Order everything from PureMS.com! They have about 99% of everything you need to repair your car and If they don't have it they can get it. If you can't install it they can do that too. Support your local VW scene

**Bierbau** · 07-31-2012, 07:21 PM

First thing if you are going to be doing your own work buy a bently manual.
Other places in SD area to get parts is VeeParts, they have a ton of MK2 stuff in stock. North Side Import parts is another option.
I also use Parts4VWS.com & Concept1.ca (they are in Canada)
Another place that has a bunch of MK2 parts is Parts Place inc., their website doesn't have all the parts on it but they will send you a free catalog which has a ton of stuff in it. Good luck with the new car!