VdubEd's Mk1 Cabriolet 'Felix'

[VdubEd]

Hi everyone, so I thought I’d finally start a thread for my Mk1 Cabriolet. Some of you may know me from club meets and previous posts.
I’ve got some issues at the moment and I’m hoping there’s someone out there can help me find the solution to my current Mk1 woes.

Ok, brief history of “Felix” my red Mk1 Cabriolet. (1990 1.8ltr, K-Jet). Called Felix after my brother who was born in Osnabrück in the same year it left the Karmann factory.
I’ve had it for a few years now and it my daily drive, i've also driven across most of East & South Australia in it.

Work done to Date:
- Cylinder Head Ported
- Techtonics Tunning 266 Cam
- Heavy Duty Springs
- Jetex 2” exhaust with Straightline Performance Extractors
- New Mohair Roof
- Some chrome parts - hoping to do more

Planned for the next couple of months:
- Rear disc brake upgrade (ship with all my parts arrived today and they're waiting to be picked up from Mascot)
- Re-trimmed interior (planned to be completed after christmas)

And a few pics:

[IMG]<a href="http://s772.photobucket.com/albums/yy6/eddieppe/?action=view&amp;current=7914eee7.jpg" target="_blank"><img src="http://i772.photobucket.com/albums/yy6/eddieppe/7914eee7.jpg" border="0" alt="Photobucket"></a>[/IMG]

[IMG]<a href="http://s772.photobucket.com/albums/yy6/eddieppe/?action=view&amp;current=d2bf9113.jpg" target="_blank"><img src="http://i772.photobucket.com/albums/yy6/eddieppe/d2bf9113.jpg" border="0" alt="Photobucket"></a>[/IMg]

OK; so the troubles I’m having at the moment:

Started a few months back that I was having cold start problems and misfires until the engine was warm, it’s also running lean. This was all going on whilst I was having teething problems with the new exhaust and the gaskets kept going at the head. Clearly it’s pretty difficult to tune anything when the exhaust blowing something crazy at head. Anyway after getting the car back from the exhaust shop last time I found a vacuum leak at the base of the intake manifold. I replaced the gaskets as well as all the vacuum lines. Excited I thought it should be fixed I drove it up to the hunter and after a couple of hours driving around up there one of the exhaust gaskets went again. After a long and painfully noisy trip back to Sydney I replaced the engine mounts with polyurethane ones (thanks Aydan gldgti) and took it back to the exhaust shop to be patched up again! (4th time).

Anyway since getting it back the cars pretty much un-driveable when cold. It idles at around 400rpm and has no power under 3000rpm . It misses and stumbles and has massive flat spots in acceleration. Once it’s up to temp the idle isn’t so bad but it still sporadically loses power and misses. Since the problem first started I have replaced the oxygen sensor and coolant thermo time switch. I’ve checked the timing and there doesn’t seem to be any problems there. I’m thinking it’s probably fuel system related, any advice would be great!

Thanks in advance, Ed

[roccodingo]

Hey Ed,

with the car running ( idle) close the throttle switch ( close the full throttle switch only, not open the throttle) if the idle rectifies itself then the ox sensor is toast or the wiring to it is damaged.

I changed my K E Jet back to K jet basic, runs way better ( no cat convertor, lambda or ECU ) Installed a TT 268 cam, 2 1/4" exhaust, Mk3 ex manifold and TT downpipe. Still needs to go back to the dyno tho. Stock tune was about 68 HP at the wheels ( 1.8 JH with Aussie emissions, 100k on the engine.) I know the 93 has a idle boost circuit as well, will dig out the relay number so you can check if the 90 has it fitted.

If your needing the KE parts I have all the electronics + wiring harness saved.

HTH

Pix fixed

[gldgti]

wow Ed! the car looks fantastic!

I can't offer you any more than roccodingo has said with respect to the k-jet, never had much of a chance to play with it myself. Best of luck is about all I can offer there.....

wheels look tough!

[VdubEd]

Thanks guys. Appreciate the advice. I would be interested to know about the relay. I've notice same arcing / electrical cracking coming from the fuse box recently when driving.

See how I go today but doubt I'll get a chance to look at it in this rain! Cheers Ed

---------- Post added 24-11-2011 at 04:33 PM ---------- Previous post was 23-11-2011 at 07:32 AM ----------

Rocco FYI, i found these images of Mk1 Cabriolet relays. I'll check ém against what i've got tonight.





I haven't been at home to do anything to the car yet (and it's been non stop rain) but i'll let you know how i go on the weekend! Thanks again

[roccodingo]

Your's will have an extra large fuse fixed to the top for the power roof. LMK if you need a wiring diag for the Idle control relay, had to piss about with ours a bit to make it work. If you have aircon ( aussie aftermarket junk) it will prob have another idle solenoid fitted as well. Might be some pics on the cabby thread i did ages ago.

[chortle]

This might help a bit.

The Mk1 Golf Owners Club: You have been blocked

[VdubEd]

Thanks guys. Problem has been located. It's a fuel injector o ring that's leaking. Or at least that one of the problems! Interested to check out these relays as well though but will fix the leak first and hopefully that will get me moving.

Rocco in response to you message on my post about the rear disc brake upgrade, i've got bias valves from a mk2 Gti, I assume these will do the trick?

Cheers, Ed

[roccodingo]

Yep, check for vacuum leaks at all hose joins etc You will want to change both the top and bottom injector o rings whilst you got them out.

Good idea to have the mixture checked and reset in having a different exhaust fitted ( possibly causing the run lean condition )

If the Prop valves are marked 3 -15 then all is good. The drum brake version is 3-35 from memory (= closing pressure is to high ) Check Pete Jones' thread, there's pics in there somewhere..

[VdubEd]

Thanks rocco, I had a bit of a search and came up with this from previous posts:

These are the prop valves in the thread.


but i have these adjustable ones, from Mk2 that i have. The closing pressure says 35 on the valve, but i am assuming that by adjusting the these mk2 valves I will be able to get the Bias correct? as they are loaded to be adjustable dependant on the load on the rear? When i bought them in UK the guy who sold them to me seemed pretty sure they were the right ones for the job, i hope so anyway?

[GoLfMan]

nice looking rig mate! Best of luck with the issues

[VdubEd]

Thanks mate, just need to get the final two injectors out. Jesus Christ they're hard to get out. Any got suggestions, I've just left them with a good dose of wd40 hoping they might pop out a bit easier tomo

[roccodingo]

Thanks rocco, I had a bit of a search and came up with this from previous posts:

These are the prop valves in the thread.


but i have these adjustable ones, from Mk2 that i have. The closing pressure says 35 on the valve, but i am assuming that by adjusting the these mk2 valves I will be able to get the Bias correct? as they are loaded to be adjustable dependant on the load on the rear? When i bought them in UK the guy who sold them to me seemed pretty sure they were the right ones for the job, i hope so anyway?

Not sure about using the axle adjusting valves as pictured. You will have to do more research. Gotta remember the MK1 is a lighter car than a MK2, Although the cabrio is heavier than a std Mk1. Have a read in the manual and see if the Mk2 valve you want to use is adjustable, I am under the impression all you adjust is the preload on the lever with the spring position ??

Could always try using a pair of adjustable valves and trial N error ??

[VdubEd]

Yeah I think the adjustable valvs and trial n error will be the way to go for the simple reasons they easier to find and cheaper!

[mikinoz]

Are you upgrading the front brake diameter? The issue as I see it is that the discs on the back are not too much smaller than the brakes on the front so as they have less weight on the rear are prone to locking earlier. In the event that you upgrade the front disc diameter, and increase the stopping force there, I would assume that the bias would move forward even with the std proportioning valves? I am no expert, but just putting my idea forward.

[roccodingo]

Rear discs require a lot less operating pressure than comparable drums, hence the difference in the cut of for the valve pressures.

Drums = 35 Bar, discs = 15 bar. ( so I am led to believe this is what the numerals identify )

I understand what your saying Mik. Changing to larger discs on the front will increase the mech advantage and hence improve the braking.