Hi all, great site i have introduced myself in the newbie section.

As i say it's my sister-in-laws 2002 Fabia 1.4 16v Elegance (AUB) that i am working on.

we recommended it to her as my wifes Polo is so good... she paid £1600.

so, the car strips the twin cam link belt of teeth and royally bends the tappets.

I sourced a 2nd hand replacment head and used the original cams.

New head gasket and stretch bolts

liquid gasket between cam and head.

EGR was all blocked so that was cleaned... rough idling, and VERY roocky engine before it laboured and stalled.

Enter Briskoda and I purchased a memoscan VAG reader EBay £13.

I had the following codes:

16685 - Cyl 1 misfire

17526 - ????

17513 - 02 short Bank 1 Sensor 2 - FIXED BY REPLACEMENT LAMBDA SENSOR

16522 - high voltage on 02 sensor B1 S2 - FIXED BY REPLACEMENT LAMBDA SENSOR

17961 - Barometric sensor

17912 - intake air bypass leak

I have replaced the Lambda Sensor and the MAP sensor. I have leaft battery unplugged for an hour and made sure it was topped up. Redex in New fuel.

I have tried different Coilpack from replacment head setup.

I have quadruple checked the timing marks.

HT leads have an ohm resistance of 5.4 except one wich is 5.

erased codes.

NOW engine runs on key, shudders while roughly idling and hunting.

upon accelerating it picks up but then the EPC and ENGINE MGMT lights come on...

The codes i still have are:

17961 - thought map sensor would fix this...

16685 - Cyl 1 misfire MAIN ISSUE I THINK

16684 - misfires blah

16687 - misfires blah

whats next guys? I need guidance, i am great mechanically but autoelectrics is not a home pastime.

cheers in advance and sorry for long post but I wanted to include all background.

ok, have you checked compression first? they can suffer from worn valve guides and that causes the valves to not seal, coilpacks play up too.

you set the crank timing at the right mark as there are 2 on the engine one says 4v next to it this is the one the ground tooth should line against.

they really do not like any inlet air leaks so go around everything again, throttle body off and a bit of grease around the rubber seal, if still no good try blanking the egr off as that could be stuck open and as it was blocked would have sealed itself so cleaning it out could have caused the air leak.

no 1 is compression test tho.

A friend is bringing me a compression tester tomorrow. I have blanked off the EGR by using a blanking gasket each side of the valve. I have wrapped Insulating tape around the throttle body head to airbox to get a nice tight fit.

the timing was done as the kit suggested... the two cams locked by using a bolt through to indents in the head casing like 2oclock and 10 oclock facing each other. the lower crankshaft was done with the shamfered tooth in line with the timing mark which is about 1oclock on the block. i didn't see any 4v but will go check. is it that likely TWO coil packs are bust?

i'll also remove the air intake maifold and grease the seal before refitting.

i'll post results.

Coilpacks do indeed pack up, these engines also eat spark plugs, it may also be running too lean and misfiring if the ECU temperature sensor is telling lies, they usually need replacing around ten years old. Thermostats stick open so the head doesn't get hot enough, gauge will read a quarter instead of half during normal running if stuck.

Edit: Also the EGR valve will not be doing anything at all until the engine is at normal operating temperature.

Edited 11 June, 201313 yr by sepulchrave

got new spark plugs, getting new HT Leads. which one's the temp sensor?

Do a compression test before you throw any more money at it. As jim says above those engines are a proper bugger for premature valve guide wear, I've seen ones with less than 40k on them with guides worn so bad that you can move the head of the valve over 10mm either way.

some motors have 2 marks, coilpacks do play up quite a bit too.

don't worry about sealing the throttlebody to the airbox for now the engine has no way of knowing of any leaks there, but an leaks however tiny from the throttle body to the engine will give all sorts of problems

ignore me if im being an idiot, but have you run basic settings with Vagcom? i could never get the ECU to reset properly by just disconnecting the battery.

Just alot of readings would be saved from the last MAP & Lambda sensors combined with the rest of the work you have done

as the EML comes on when you rev it, it cant be purely mechanical, surely?

Temp sensor is under the coilpack, it's blue, four wires.

this is great thanks guys, so...

I have to buy new HT leads as i pulled one out when ohm checking doh!

so i'll try and post a photo of the timing... the shamfered tooth is on the righthand mark say 1 oclock and the line on the crankshaft pulley is dead centre 12 oclock in line with leftmost mark.

I looked for the blue temp sensor but didn't see it... is it the one in the plastic coupling from rad pipe to head?

my VAG reader is simple, i did an erase to clear the codes as well as battery disconnect... i do not know how to do a 'basic setting'..

Kyle

what measurement am i looking for on the compression test?

what measurement am i looking for on the compression test?

Just get maximum readings for each cylinder and compare the values, they should all be similar. Post them here.

Yes, the temp sensor is on the plastic housing you describe.

Disconnecting the battery returns the ECU to base settings.

Hi all,

so I have a compression tester. I get in kg/cm2 'cyl 4 - 11' 'Cyl 3 - 10.5' 'Cyl 2 - 11.5' 'Cyl 1 - NOTHING!'

I removed the cam head and wasn't sure if once it was on the tensioner that it made the cam to cam belt one tooth out so reset the belt... could this be all it is? or should i go ahead and remove the HEAD again?

If I do remove the head then release the valve springs to reseat valves do i have to cut the valve and seat or can I clean and lap grind them back in?

Am I OK to reuse the same valve?

I feel I am on the road to the end now...

thanks for all input.

it's pot luck with those cylinder heads, sometimes you can get away with it, I've seen them in the past with mis machined valve seats from the factory, or it may be a burnt out exhaust valve but I would have thought you would notice that when you assembled it.

you need to whip the head off and have a look, if the seat needs re grinding i would just throw the head away and stick another one one there.

Sounds like some valves on cylinder 1 are not closing, possibly bent and sticking in the guides.

I had a misfiring problem on mine, It's the same engine (AUB). Mine turned out to be a coil pack if that helps... Weren't too dear either

^^ yeah coil pack Is always a good shout, but there is obviously a mechanical fault on this one if there is no compression n number 1.