Anyone familiar with MKII VW tech?

[riverdale21]

I just recently purchased a 1985 VW GTI 16v to add to my little fleet of toys. I haven't found any decent VW forums out there. It's hard to compare forums after using this kickass one for so long.

Anyways. I am having some trouble with my little kart. It has been idling at about 2000 RPM and I have been averaging only 10.5 MPG. And that is mostly highway driving at 65-70mph, not exactly lead foot territory. According to Edmunds.com my engine (from a 1991 Gti 16v) should be getting 21-28mpg.

Anyone know what is going on or can point me in the right direction?
I have checked out VWvortex.com and I didn't really find anything there.

[Julien]

contact "dirtygerman" on this forum.. he's a mk2 16v guy



hth
ju

[dirtygerman]

Re: Anyone familiar with MKII VW tech?

No problem, first check what type of 16v engine your car has.. No 1985 came with a stock 16v.. they had 1.8 16v's and 2.0 16v's in the later cars your car has a swap, in the US they were the PL and 9A engines.. How are you noticing your getting crappy mileage are you going by the MFA (multi-function unit) or did you fill it up and test it.. MFA's are usually wrong they are run by vacuum.. the little hose comes undone alot in the back of the cluster and other things... Find out if you have a PL or 9A engine first and let me know how you came up with those MPG readings..

If you have a 1.8 16v you probably have 4 braided fuel lines coming from your distributor CIS-E, if you have 2.0 16v you have motoronic which was offered on the later GLI Jetta's and later GTi Golf's and Passat of those years which has a MAF box... get back with me.

[riverdale21]

From what I understood from the previous owner is that this is a swap from a 1991 Gti 16v. He said it was a 2.0. I will have to see what the engine code is. Right now I'm at work.

I was guaging gas mileage by a combination of both the MFA and by the amount of gas in my tank. I don't know how big the tank is on this little bugger but I filled up the other day when the needle was low and I was able to pump in 10 gal and change.

When I get more definate info on the engine code I'll let you know.

As far as the high idle could that just be a vacuum leak?

[dirtygerman]

You have a 9A engine code im positive. The tank is 14.5 gallons.. fill it up and do the whole testing thing, and lets go from there... as far as your idle try spraying out your ISV first.. Idle Stabilizer Valve.. with some carb cleaner alot of gunk will come out of it most likely.. if that dont help post again.. im at work too ;)

From what I understood from the previous owner is that this is a swap from a 1991 Gti 16v. He said it was a 2.0. I will have to see what the engine code is. Right now I'm at work.

I was guaging gas mileage by a combination of both the MFA and by the amount of gas in my tank. I don't know how big the tank is on this little bugger but I filled up the other day when the needle was low and I was able to pump in 10 gal and change.

When I get more definate info on the engine code I'll let you know.

As far as the high idle could that just be a vacuum leak?

[riverdale21]

Know any decent MKII sites or forums? I looked around www.carlynx.com but couldn't find anything worth while.

[e30fiend]

http://www.vwvortex.com is a pretty damn good site, and the 16v engine forum is one of the largest technical forums on the site. What exactly are you looking for that you didn't find?

[cramer]

vwvortex is the best you're going to find. Check the techinical 16v forum

http://forums.vwvortex.com/zeroforum?id=35 lots of good info there.


I'd first start with the basics, have you changed your fuel filter? (this is something that never hurts to do)

Any fuel leaks? The Mk2's can leak around the fuel pump, my Fuel DPR (on top of the airbox) leaked, very expensive part... and check the conditions of your lines. You may be leaking more fuel then you're using.

High idle can be adjusted down, The ISV may need to be cleaned or you can have a leaking gasket on the idle screw.

[a32guy]

I believe there is also an idle adjustment near the airbox on 2.0 16v's. Can't quite remember. But my money is on ISV. Try a local junkyard and grab one off an early 16v passat. They are pretty common.

By the way, nice to see fellow vortexer's on here! :D

[riverdale21]

I'm nice and relatively new to the whole VW scene. Is there a company that is equivalent to BMP Design / BavAuto as in provides a one-stop solution to VW stuff? Whether its restoration parts or performance.

[dirtygerman]

www.germanautoparts.com << good service

https://www.parts4vws.com

https://www.autohausaz.com

I'm nice and relatively new to the whole VW scene. Is there a company that is equivalent to BMP Design / BavAuto as in provides a one-stop solution to VW stuff? Whether its restoration parts or performance.

[cramer]

i'll throw out a couple more

https://www.evolutionsports.com

www.worldimpex.com (was vwparts.com)

those are the two i get all my parts from :)

[Werksmini]

I get all my replacement style parts from parts4vws.com There good people. Ive had a shitty idle for like a year. I even got the head rebuilt bla bla bla. For me its the injectors, but the 16v is one of the most fickle motors ever produced, there are about a thousand things that could be wrong. But I would check the idle switch and the Idle Control Valve or whatever vw calls it. I would doubt that a loose vaccum hose is the culpret. Good luck, and have fun.

[rahmin]

my old 16v did this and I couldn't sort it out. mine was also super groggy between 2-3500 rpm. I spent many evenings in the garage with tracing and replacing every vacuum line. Then the isv and on and on. i finally gave up and took it to a shop after i spent a week with a multimeter hooked to fuel distributor (cis-e 16v) to adjust the fuel mixture. The shop hooked it to a 4-gas analyzer and found that I had a major vacuum leak from my fuel injector seals. They diagnosed and replaced the seals for about 150. After that, I had better gas mileage, an amazing factory-like idle and much more power. Good-luck and enjoy your A2 because I really miss mine.