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Thanks for the answers. Cepheuz, you mean pics of compression and vacuum readings in plug holes? I narrowed down to the possible fault of the crankshaft (=speed) or the camshaft sensor. I'll try to clean / re-fit them. If still nothing, I will replace them. If none of this helps, I will buy a compression kit, and check cylinder compression.

Hi! Just this short question: I am working on the engine (it has a very rough idle), and for a short time I need to start it occasionally to see if the problem has changed. Can I start the engine when black engine cover is off? It is also the housing for the air filter, so no air filter in this case: the throttle body is open to the air. Thanks!

Yes, I think it's misfiring. But interestingly, no fault codes in VAGCOM. I'm going to replace the crankshaft (=speed) sensor and the camshaft sensor. If this does not help, I will check the compression. Does anybody know what is the solution for the very common momentary engine cut-out symptom at steady speed (usually highway) ? Is it the crankshaft or the camshaft sensor? You can find lots of hits for this exact problem, btw it seems to be a common VW issue, not just Fabia. Just a few: http://www.ilexa.co.uk/forum/index.php/topic,15476.0.html http://briskoda.net/forums/topic/161463-faulty-camshaft-or-crankshaft-position-sensor-or-something-else/ http://briskoda.net/forums/topic/88425-14-16v-revs-momentarily-dying-on-the-motorway/

What do you mean by "missing"? This engine has spark plug coils, high-tension is creared only right at the plugs. I checked the coils with a multimeter, and they seem good.

Hi Nick! Have you since replaced your camshaft sensor? Is your engine cut-out restart problem solved? Thx

Hi Nick! Have you since replaced your camshaft sensor? Is your engine cut-out restart problem solved? Thx

Thanks for the advice. I will probably do the compression test after replacing the camshaft sensor which probably needs to be replaced anyway. Do you have any experience with this highway sudden loss of power symptom described in this thread: http://briskoda.net/forums/topic/161463-faulty-camshaft-or-crankshaft-position-sensor-or-something-else/ I had the very same phenomena occuring occasionally during the last 2-3 years. Have not checked cambelt timing. Is there some simple method or kit to check cambelt timing?

I've never tested it, and no experience in how to do it. Is it a DIY job for a non mechanic? I just hope that the engine is mechanically all right .

Maris, I have a strong feeling that the engine problem we experience might be related to a faulty camshaft sensor. The misfires I have could be definitaly explained by this. Although I don't know if your throttle valve is OK or not. A VAGCOM alignment would help. BTW, have you experienced the symptom that usually occurs at highway speed, and described as "sudden loss of power symptom"? The engine stops for a moment, rev gauge falls to 0, but the next moment everything goes back to normal. This can also be caused by intermittent hall sensor fault. And my theory is that finally this ended up in a totally bad sensor that keeps the engine even from idling. I opened a new thread for it: http://briskoda.net/forums/topic/185223-symptoms-of-faulty-camshaft-hall-effect-sensor-car-unusable/

1.4 16V BBY

Hi! In summary: I have an engine, that runs very roughly, dies when idling, car not usable. I can crank it, but if I let it idle, it will die in a few seconds. By pushing the gas pedal, I can keep it running, but the engine shakes horribly (probably ugly misfires), and no power at all. Unfortunately, no faults indicated in VAG-COM at all. (You can check this other thread in which I describe the same problem: link ) I have done the following so far: - coolant temp sensor changed - fuel filter changed - throttle valve cleaned last year. Now I just checked that it is not stuck, valve moves when pushed with finger. - resistance of spark plug coils checked, all 4 is equivalent - spark plugs changed - air filter cleaned with compressed air - ECU unit connectors disconnected, checked, reconnected - MAP sensor cleaned, air pressure checked in VAGCOM = 1 atm - fuel pump checked: pressure normal (3bar), hold pressure OK (-0.5bar / 10min), fuel flow rate 1 liter / 30 sec Not yet checked: - EGR valve (might need a clean, but don't think it causes my problem) - O2 sensor (How can you check this ???) Now I have a very strong feeling that the above problem is caused by a faulty hall effect sensor!!! The nature of the problem suggested to me that the fuel pump might be broken, but the same symptoms and misfire can be equally explained by a faulty camshaft sensor reporting faulty position readings to the ECU. Also, in the past 2-3 years I had those unexplainable occasional highway power loss syndromes (this is a very frequent problem reported on these forums, but Ive seen no reported solution so far), that may also be related to faulty camshaft sensor. My theory is that the earlier intermittent sensor problem has finally ended up in a totally broken sensor. So my question is: How frequently do these camshaft sensors die, and what are the symptoms? Do you think my problem can be connected to it?

Hi, did you perform a throttle body alignment in VAGCOM? It lasts a few seconds, moves the valve back and forth, and makes some squeaky noise.

Hi Maris, You took off the cylinder head? I still don't use the car, use the other. I will probably take it to a service station soon, because I have no ideas left. Although I'm quite disappointed after having checked lots of things. In the meantime I did some more checks, the most important one being the fuel pump. I've been strongly suspecting the fuel pump up to now, but no luck. I connected a gauge to the fuel filter output line. The fuel pressure is good (3bars), the pressure loss after switching off the pump is under 0.5bar after 10mins. The fuel flow rate is about 1 liter / 30sec, way above minimum. One last idea: Can alternator fault cause such symptoms? That is, the engine is trying to start on sole battery power (I've recharged it to full since), without the alternator delivering the 14V charge. In theory, can the engine run on sole battery power, for a few minutes at least?

Hi, The throttle body, I have cleaned it a year ago, and reset it. But now, I did not cleaned it, I just gave him a reset through VAGCOM. The EGR valve will be checked next. (At least I have to rule it out, because I would not like to buy a new fuel pump in vain :-)) How do you do the EGR valve in VAG-COM? Thx

It does not idle at all. When I first start it, it idles for longer (although very roughly), maybe for 10-15 seconds, then stalls. When I try to crank it for the 3rd ot 4th time in a row, it won't fire up. I will check the EGR valve. Is it an easy job? Interestingly, noone mentioned the fuel pump yet. Can it not be the fault? Thx

OK, I took out the MAP sensor, cleaned it thoroughly, put it back: nothing has changed. The sensor itself was a bit dirty. As I observed wIth disconnected sensor, the engine won't start at all, just cranks. With MAP sensor connected it starts, idles for a few seconds (very roughly) then stalls. So, I think MAP sensor is ruled out (for the time being).

I tried to start the engine with MAP sensor disconnected: it wouldn't fire up, but it throwed 2 DTCs (something like Manifold pressure sensor ground, and Intake air temperature value too high). VAG-COM showed 2 mbar for Manifold Pressure value. When I reconnected, it wouldn't start either. VAG-COM meas. block group 002 field "intake manifold pressure" says: 995 - 1001 mbar (the exact value varies between these boundaries). I think the value is correct, corresponds to 1 atmosphere. I am not convinced by this that the MAP sensor causes the problem. Either connected or disconnected the engine won't idle. I think Apogee's point was that if the engine is much worse with MAP sensor disconnected, then the sensor should be all right. But in my case, the engine just cannot be worse because it is totally bad already. Question1: if you disconnect the MAP sensor, should the engine start up at all? Question2: can a dirty EGR valve make the engine not start at all? Question3: can a faulty fuel pipe cause the same? How can I check if the pump delivers the correct pressure (3bar) ? Thx

UPDATE: I fiinished checking some more things. So in summary: I have an engine, that runs very roughly, dies when idling, car not usable. Unfortunately, no faults indicated in VAG-COM at all. I have done the following so far: - coolant temp sensor changed - fuel filter changed - throttle valve cleaned last year. Now I just checked that it is not stuck, valve moves when pushed with finger. - resistance of spark plug coils checked, all 4 is equivalent - spark plugs changed - air filter cleaned with compressed air - ECU unit connectors disconnected, checked, reconnected To be checked (in order of probability): - MAP sensor - fuel pump - EGR valve - O2 sensor - ignition lead (no idea how to check this) Any further tips/advice greatly appreciated! Regarding the MAP sensor: I'm going to start engine with MAP sensor connector unplugged as suggested by Ap0gee. Also I'm going to check VAG-COM measurement groups that display air pressure data. (I still don't exactly know which group should be checked, and how the indicated valued should be interpreted. What are the correct ranges?) I located the MAP sensor, it's the sensor number 4 (behind the oil dip stick): here Should I buy a new sensor, or is it just the carbon deposits that has to be cleaned off? Regarding fuel pump: is there any home method to check this? The fuel pump has to deliver 3 Bars pressure. Thanks!

Thanks for the answer. Where is the MAP sensor on Fabia1 1.4 16v (not MPI) motorcode BBY? Here is an old thread of mine with a few pictures where some time ago I tried to figure out all sensors I could see (8 pieces actually) in the engine area http://briskoda.net/forums/topic/131944-start-engine-first-time-after-6-months/page__p__1655334__fromsearch__1entry1655334. Maybe someone could point me the MAP sensor on those pictures? I suppose a MAP sensor can be tested with an ohm meter, right? To tell the truth my engine problem is not intermittent. Whenever I start the engine, and let it idle, it will die right away if I don't rev it up a bit. And also during revving it is not running well, it shakes, no power, so the car is totally unusable at the moment. But I will check the MAP sensor if it's simply a multimeter measurement.

I also got some hints that maybe the ECU connectors should be tested and cleaned. When I get to finish the spark plugs I will check those remaining things (ECU, air filter, O2 sensor via VAGCOM, fuel pump (still no idea how to check this)). OTOH, I checked some pictures regarding the used spark plug: Accrording to this http://www.spark-plugs.co.uk/pages/technical/diagnosis.htm my old spark plugs look o.k. to me, weared of course after >70000kms. I also checked what piston tops used to look like: Found these posts, scroll down to the pictures: http://forums.vwvortex.com/showthread.php?1581500 another post with pictures http://forums.vwvortex.com/showthread.php?4054146 Comparing to the above, my piston tops could be normal (at least I hope so).

Thanks for all answers. Actually, all of you have some good points there, because the engine is not running well. It runs very roughly, and it dies when idling. Overall the car is unusable at the moment. I started to repair as a DIY job: I already changed the coolant temp sensor, changed the fuel filter, checked resistance of spark plug coils, none of them helped. Now I am changing the spark plugs as my next guess. Air filter was changed 1.5 years ago, but I will check it anyway. So you say a faulty O2 sensor could also be a possible cause? At the moment I also suspect the fuel pump. VAGCOM did not show any faults. Is it possible to tell with VAGCOM if for example the O2 sensor readings are not quite correct? Any further advice appreciated!

Hi! I am changing the spark plugs for the first time in a fabia 1.4 16v with 70000 km mileage. I took two pictures of the pistons through the spark plug hole. The top of one piston is covered by this black soot/sludge, the other piston is covered only partially. Do you think it is totally normal, is it as it should be? Here is the old plug. Does the old plug look also O.K.? Thanks!

So, I changed the fuel filter. And I also bled the system! Sort of. What I did is that after I installed the new filter, I connected only the IN and RFL (return flow line) line but left the OUT line disconnected. Then I turned the ignition key into accessories 2 or 3 times, but did not crank, switching on the fuel pump for a few seconds several times. Thus the pump filled the empty filter with fuel (don't forget to put a catch can under the filter). Finally I connected the OUT line. I think with this procedure you can minimize the air blocks in the fuel line. Now about my engine problem: unfortunetaly this did not solve it, it still runs very roughly so that I can not use the car. When idling the engine always stalls. I already changed the temp sensor, cleaned the throttle. What is left: fuel pump, spark plugs (I don't think it is the spark plugs though, because all cylinders seem to be affected), injectors? But suspect the fuel pump does not deliver the 3 bar pressure. Probably it is an easy change, but the pump itself is expensive. Can I somehow check if the pump is OK. Verify the pressure with VAGCOM? Any ideas?

I already bought the filter (with integrated 3 bar pressure valve): 6q0201051b (original VW supplier, seems completely identical to Mann wk69). Actually, the engine started to run very-very roughly - affecting all cylinders so I have a feeling that it might be caused by a clogged fuel filter. I already swapped the coolant temp sensor in the thermostat, but no improvement. So I bought the filter, but now hesitating because of this bleeding procedure. No idea where I can get these valve connectors. How risky is it to omit the bleeding, really? Should I expect that the air escapes through the injectors?

In the meanwhile I found these: changing fuel filter, no bleeding done: http://www.golfmkv.net/blog/archives/10# Also found this one (VW Jetta fuel filter change procedure. You can observe the additional special adapters that are needed to bleed the fuel system): http://www.keepandshare.com/doc/990557/fuel-sysyem-bleeding-pdf-december-29-2008-3-34-pm-121k?da=y It says: "Fuel System, Bleeding Note: If fuel supply system was opened, it must always be bled before starting engine. If fuel supply system is not bled, catalytic converter will be damaged." So is this a DIY job, or should I take to Skoda service?