9a'd Mk1 - poorly

Hi everyone.

I have just converted my sisters mk1 cab from a 1.6 gli to 2l 16v from a passat (9a engine code)

The car isn't running very well, the engine was running fine when removed from the passat, but since i have changed the cambelt and also the cams for kr ones, i have also used a scirocco inlet manifold with injectors/lines etc.  The timing is, i think spot on, here are some pics….











the bottom end has been timed up to the mark on the pulley/lower cam belt cover which also lines up with the dot on the flywheel.

at the moment, im using the 1.6 metering head but have also tried the 1.8 16v metering head, i have run with and without the cold start valve connect and also WUR connected, no differnces were scene.  

The idle is extremly lumpy, it doesnt rev well and will not hot start at all, new sparks plugs were fitted at the time of conversion and are now after a bit of idle and driving around the block, black.

not sure where to go from here, im a bit unfamiliar with the 16v engine and tbh k-jet itself. I'm thinking a bit of ignition timing and CO adjustment might be the answer but any other suggestions would be greatly appreciated!

Not too familiar with the 16v myself, but timing and mixture would be my first guess. Have you got any picking at all?

Is the new cam a high lift one? This will cause the idle to be lumpy.

Jay

the cams are from a 1.8 16v (kr engine code), just a tiny bit more lairy than the 9a cams.

I don't think its the timing, you've been careful enough to align everything as it should be. Definitely worth checking you're getting ignition advance from both vacuum and 'mechanical' (of course its not mechanical because its done by the ECU, but its the advance from higher engine speed). Then do normal ignition checks (clean leads, check plugs, plug gaps, leads pushed in properly, etc). If you still have a problem it could be the fuel system - faulty WUR, or clogged fuel filters, etc. Which idle system are you using?

faulty WUR is possible i suppose, to me it is unknown, a friend of mine does have a known good working one which i can try.

Leads, cap, rotor arm etc are all good, forgive my ignorance but how can i check the ignition advance as it should be controlled by the ecu?

At the moment im not using any idle control (which i know isnt helping matters, but i know people who have done exactly same conversion and only used the mk2 16v ecu for ignition), i'm going through the wiring diagrams and will be using the mk2 16v isv etc.

What about the hotstarting issue? it just doesnt even try to catch, and obvioulsy after a while of cranking the engine floods.

You can check it advances with rising engine speed, by using a timing light and revving the engine. You can check if it responds to vacuum, by pulling the vacuum connection off the ECU and seeing the timing change (using the light).

Hot starting could be down to improper mixture, or ignition timing, or just poor compression, etc.

Many thanks for your advice paul!  Hopefully i'll have the mk2 16v isv and everything that goes with it in by the end of the weekend, i'll check the vacuum then as i have a timing light, then will just need to get the mixture set correctly - i think this is the problem with hotstarting.

Well the mk2 16v isv is in and working as it should, the cold-start, wur and thermotime switch all seem to be working as they should too but still runs exactly the same,

Im off outside now to try a another wur, we'll see what happens…

Have you measured the mixture at warm and cold?

new spark plugs goin black from new on a tootle round the block?
wouldnt that suggest mixture?

changed the wur and didnt seem to make any difference,

i do need to check the mixture, tried both 1.6 8v metering head and 1.8 16v metering head both seem to run the same.

that was antoher query i had, i heard that the 1.6 8v metering head was better than the 16v one? is this true?

You need to reset the mixture if you swap a WUR anyway! Doh!

oh right, ok,

all this k-jet is new to me, give me a vr6 any day of the week! lol!

K-Jet isn't that hard, but these days its a bit unusual and works in weird/wonderful ways!

prob a bit daft but you did fit the lambda probe didnt you as this was one of the reasons mine was so lumpy to start with ops:  ops:

I pull a good pint but wont make no mechanic 8)

K-Jet doesn't have a lambda probe. KE-Jet does. So, which one was fitted?

My 9a was from a pasat gt. If yours was the same might be thinking about.

Tim

Mine was from a passat gt too, but im not using the ke-jet which uses lambda, im using k-jet

how far up should the flap be on the metering head with the engine turned off?

im guessing it should be closed?

yep, so the problem was overfueling, the flap on the metering head was suppose to be closed, which it wasn't, a little sping underneath the flap keeping it open, all fixed now!

now just to finish everything else off.