OK...so today I was stuck in traffic and noticed the revs a little low on tickover. As I pulled away the engine felt very lumpy It was immediately obvious that all 4 cylinders weren't powering the car. Previously (only 10 minutes earlier) it was pulling perfectly fine on the dual carriageway with no loss of power at all.
I limped home and whipped off the engine cover. I checked that each coil pack was producing a spark from the end of the pack itself (main plug) and also the HT lead to the opposing cylinder's secondary spark plug. All seemed fine and dandy
I removed each of the spark plugs for inspection. They all seemed fine excpet for the ones from cylinder 3 which were wet...so this was clearly the cylinder not firing. I dryed off the plugs and swapped them with ones in another cylinder just to confirm that it was knackered plugs. Ran the engine for a few minutes (still lumpy) then checked again...all the swapped plugs in both cylinders were dry I wasn't expecting that so back to the drawing board.
So...now I'm not sure which cylinder is the problem and whether it is the spark plugs that are at fault. On the service history is does say the plugs and leads were all replaced about 3 years ago due to a misfire and the car has done less than 20k since they were all changed. I believe that these plugs are supposed to last a long time (60k??) so I'm not sure why they would have given up so soon if it is the fault of the plugs. Is there any easy way of checking which cylinder is not firing and if it is really the fault of the plugs? The TS malarky seems a little more complicated to diagnose than a standard 4-plug setup. I guess I'm right in saying it is the large plug on the end of the coil pack is the one that does the actual firing? (what does the spark from the other plug actually do? ).
Anyway...if anyone is able to give me a few tips or pointers on how to diagnose which cylinder is the problematic one and how to actually tell if any of the TS plugs are at fault I would be very happy. If the plugs weren't so expensive I would just go out tomorrow and buy a new set to give them a try but it is bound to be sods law that if I do that it will turn out not to be faulty spark plugs at all
I would say dodgy lambda also, as thats what mine felt like, apparently the engine will run too rich, causing the plugs to foul, hence the three cylinder running.
there are cheapo versions of those plugs available, just wont last as long, could use them for elimination purposes. The second set of plugs is to clean up the emissions IIRC.
Not had a lambda go so unsure of symptoms but many have. The plugs are japanese, the lambda, Bosch, which is most likely to fail..........??
Cheers for the suggestions guys...at least I have somewhere else to start looking as I wouldn't have even considered it could be the lambda sensor. I'll have a butchers and see if I can locate it...I guess it is somewhere on the exhaust after the manifold. As it looks like I'm now going to be working outside tomorrow I expect it to be raining in true British weather stylie
It guess it may still not be the problem but it's definately worth a look. It just seemed a bit odd to me that the plugs would suddenly let go while on the move. If they were beginning to break down I would have at least expected misfiring to occur first before a total all out complete non-firing of one or more cylinders
Does anyone happen to know the rough cost of new lambda sensors off the top of their head? Is it better to stick with the original Alfa supplied Bosch one or are other ones just as good? (I notice that Lucas appear to do some and I'm sure other manufacturers do too).
My MPG was very poor in the lead up to the Lambda going pop... a tell-tale sign apparently. The garage fitted mine and used a factory spec Lambda. Car has been running like new ever since.
There are others available and Symon has had a good result with the one he picked up on eBay.
What type are the plugs that were fitted 3 years and 20k ago. Indeed correct plugs have a life of 60k but are yours genuine or a cheaper type?
They are actually NGK plugs (written on the ceramic top of each plug). The invoice lists them as BKR6EKPA (x4) and PMR7A (x4) at £64 for the lot so unless the garage lied it does mean the proper plugs have been fitted
The more I think about the problem the more I'm beginning to wonder how the lambda probe could cause it to run so badly (if it is indeed the probe at fault). It really does sound like a tractor...not just slightly lumpy And can a lambda probe just give up like that mid-way through driving?
Is there any way of testing the lambda probe for a fault rather than just taking a pot-shot chance by replacing it? Like the plugs, it's a an expensive part to buy (about £95) so to replace it and then find no difference would be a real bummer.
Maybe I will try to take an audio recording of the engine running later on and post it up if I can.
It's like a spagetti junction of leads down there Is it possible to disconnect and remove the secondary plug coil packs & leads during the diagnosis process (i.e. in a 'normal' running engine would the lack of a spark in the secondary plugs make a noticable running noise difference to the engine?).
unplug the lamdba see if it makes a difference, the connection is on the bulkhead, mounted in a small cover in line with the steering wheel, rubber plug type connection.
Thanks...I just tried this (I assume you mean the blue plug with 3 pins...the only plug I could find in that location) but unfortunately unplugging this makes no difference whatsoever
The coils that fire all the main plugs are the 2 on the far left and I now know that the secondary plugs fire a split second after the main ones (not 180 degree afterwards) so to eliminate any complications I completely removed the coils and connections to all secondary plugs. With this setup, it is no better (I wouldn't expect it to be), but it is also no worse.
The strange thing is that with this simpler 4-plug connection setup, if I remove either of the coils (plugged into the left 2 cylinders) from the spark plug then the engine almost stalls. However if I remove the slave leads to either of the right 2 cylinders then ther is no change in engine running To me, this suggests that BOTH cylinders on the right aren't firing. However, I have proved that a spark is being produced from those 2 plugs by removing the plugs, running the engine then placing the spark plugs (connected to the slave leads) close to a grounding point on the car.
The more I try and diagnose the problem the more confused I am getting and I am now beginning to wonder if there is some electrical fault somewhere which is not firing the sparks at the correct time. Maybe I am just going to have to admit defeat and limp it down to the stealers
The attachment below is the (not nice) sound the engine is making with all coils and leads attached...
LumpyRunningEngine.mp3 ( 159.69k ) : 411
Have you tried unplugging the MAF? To see if this makes any difference. The ECU will go into limp home mode, and if it was the MAF it should run better, although not as good as normal. Though others may say that if the MAF is totally stuffed it will make no difference if it unplugged. Maybe someone else here knows more than me.. ?
Another suggestion would be to disconnect the battery for an hour or so, it may reset the ECU.
Failing that, I would be tempted to get it hooked up to a diagnostic system. The going rate is about £50.00 - it could save you so much time and effort.
if you have prooved that you have sparks on the two cylinders that dont seem to effect the running of the engine i.e slow down any more. Have you checked to see if the injector's are actually squrting out any fuel, you may have injectors that arent firing or are blocked.
If you remove them one by one and get someone to try and start the car, they obviously should squrt some fuel be sure to catch it in something, like a rag or something
jam...I will try out your suggession (unfortunately not until the weekend now) but looking down the spark plug hole, the tops of those two pistons were certainly wet so some fuel is definately getting into them. Whether or not there is some kind of intermittent injector fault though I couldn't really say so I will whip out the injectors and try them anyway to see if there is any kind of obvious problem with them. I wasn't really too sure about the safety of doing this but I guess it should be ok as long as I don't start squirting fuel all over the manifold
Anyway, I actually bit the bullet this morning and booked it in with the stealers. The earliest they could fit me in was in 10 days time and that was only because they had a cancellation. I guess the only consolation is that it will give me more time at the weekend to do some more of my own checks.
Cheers for everyone's help so far
I have now removed the injectors and checked each one...they are all producing a powerful spray of fuel so that isn't the problem either.
With the engine running I have been round and unplugged any connector I can find in turn (just one at any one time) with exception of the ECU obviously. None of them unplugged change the running of the engine with the exception of the brown one which stops the engine completely so I can only assume this is to the fuel pump.
I now believe the car is actually only running on TWO cylinders because if I unplug either of the injectors on cylinders 3 of 4 nothing changes, but if I unplug either of the injectors on cylinders 1 & 2 the car nearly stalls.
I am now beginning to think the problem is a lot more serious than I first thought and WHITE smoke is puffing out of the exhaust Is this a normal symptom of a car running on only 2 cylinders???? (i.e. is it just the unburnt fuel from the other two cylinders?).
It's booked into the stealers on Thursday but now I am beginning to think that my bank account is going to be rather empty by this time next weekend It's sods law...my other (Italian) car which I've had for over 9 years hasn't missed a single beat in the engine department even though it used to be my daily drive, but this 6 year old Alfa which has less miles on and which I've only had for 9 months has already broken down in what seems to be a serious way
I just did a bit of research and white smoke suggests blown head gasket or worse still, a cracked head Is there any way to tell of a dead head gasket without removing the head?
Does anyone know roughly what the damage would be for getting a head gasket replaced by a main dealer (assuming the head itself is actually OK)? I guess this is quite a labour intensive job
The top end was completely rebuilt only 15 months ago (previous owner) following a cambelt failure.
My Girly's MGF had a Head Gasket Failure... very common on K Series engines. I don't know how, but there are tests that can be done to confirm any failure.
Symptons were - a smokey exhaust - running very rough until warm - coolant loss and water in the oil.
In the end, the oil was a coffee coloured creamy substance.
I wish you the best.
had this on my Saab. There is a test that involves putting a vessel containing a liquid that changes colour in the presence of carbon monoxide in place of the rad cap. If there is CO present it changes colour, often the fault will cause a lack of compression as the pressure seeps to the neighbouring cylinder, also causes water loss, in very extreme circumstances it can result in oil in water or vice versa or that mayonaise type crap under the oil filler.
THe cost for the Saab was £300 at a specialist, but as that was a chain driven engine they did not insist ona belt/bearing/variator/water pump/oil pump change at the same time.
I have checked the oil and the water and there is absolutely no sign of cross contamination. I also been out again this afternoon and with the engine running the car is no longer producing white smoke anymore
I decided just to let the stealers loose on it as originally planned otherwise I may end up spending far more money unneccessarily as I still don't really know what the cause of the problem is.
OMG, YOU HAVE GONE TO A DEALER??? let us know the diagnosis before you authorise the work. please!!!
the lambda connection is under a black cover at the rear of your engine bay, it just slides upwards and off, and there you'll find a 4 pin connection. and yes, it'll smoke lots of colours and smells if overfueling due to lambda probs
Bo****ks! I just had the diagnosis done and the result is the timing has (somehow) gone out and apparently trashed at least 2 valves. The full extent of any other head or valve damage won't be known unless the head is removed which hasn't yet been done.
The garage has quoted me around £2000-£2500 to do the work dependant upon actual damage and are fully booked up for the next month work wise so wouldn't be able to do the work for quite some time. Obviously I told them NOT to proceed because the whole car itself is probably only worth this amount (with a running engine) so economically it doesn't make sense to pay out this sort of money for repairs. What p****s me off more than anything is that the previous owner had this head completely rebuilt only 2000 miles ago (15 months ago) How on earth would the timing go out like this? I checked the belts last weekend when I was trying to diagnose the problem and not only did they look okay but they were as tight as you like.
I think the only real sensible option money-wise is to tow it back and do the work myself. Maybe it is worth looking for a reconditioned head rather than getting my own repaired (again) in case there is some issue with it and also bearing in mind it's been skimmed once so may already be on the limit. Does anyone know of any places I could look for a new head?
(BTW, the garage it went to wasn't a dealer but an Alfa specialist which I didn't actually realise until yesterday )
The best place for a head is eBay if you are patient. Other than that you could get one from a scrapped 145,146 or 156.
However I don't see a problem re-using the head if there is nothing wrong with it.
Expect to pay £700 in parts (thats what it cost me although I did change a lot of other stuff at the same time such as plugs, thermostat and filters) if you recon your old head, and £50 or so if it needs skimming.
Where did you get your head reconditioned out of interest?
I will probably try and reuse my current head if it doesn't need a reskim, or it does need a reskim and hasn't already been skimmed to it's minimum limit. But, if I do go for an already reconditioned head (I guess they would be on an exchange basis?) then are there any differences between the phase 1 & 2 engines (alloy/plastic cover tops) that I need to be aware of?
I took it to an engineering place and got the valve seats cut but the rest was done by myself.
It should not need a skim. I didn't skim mine, its only really a precaution when the headgasket goes. Just check the head with a straight edge to make sure it isn't warped or anything.
There are no differences between phase 1 and 2 other than the stuff that is bolted to it. Just be aware that 1.6 and 1.8 heads are the same, but the cams are different
I don't know anywhere that recons Alfa TS heads, although I wouldn't be suprised if there is. I think Poweralfa (in AJ's opinion the worst supplier ever known to man) sells the bare head on its own for £700.
That sounds like a good deal actually. If not a bit too cheap. The headgasket and bolts (set) are £50 each, alone.
I think what I will do is get the car back home, get the head off and if it isn't warped then I will give this guy a call and find out the score. My bet is that he will offer some kind of guarantee but I will ask.
It should be relatively straight forward getting the head on and off by following the manual (just time consuming). The hard bit (which I won't be looking forward to) is probably going to be getting the belts back on. I will obviously get some cam locks and go from there.
I reckon you'll just need a few new valves, a valve spring compressor, some grinding paste and one of those rubber suction cup thingies?
(I usually get lazy and put the top of the valve in a drill chuck to grind it in.)
As far as I've ever seen the valve ends just bend a little and then stop hitting the pistons so your head should have survived.
Hi Peter. you might be right. I guess a complete recon is the worst case scenario and seeing as all guides and valves were already replaced just over a year ago, the guides (and most of the other valves) may be perfectly OK. My dad has a spring compressor in his drawer somewhere that I can borrow and a little elbow grease grinding in a few valves shouldn't be too much effort. I guess I will only really know what route to take once I have got the head off and can inspect the damage.
Look for a 156 2.l head.
there the same part number. Plus there easyer to come across.
Once you get her running again, change the oil and then after a few hundrad miles **BUT** keep to the same make and grade oil. Don't change it.
This is how i trashed my head, by using different oils.
for a complete valve/guide overhall, theres a guy near bicester in oxen that does the whole lot for £275 + vat, and thats worst case scenario replacing the whole lot. he does heads for me and the local stealer, so does a lot of twinny heads.
Well today I started the task of stripping the engine. With the engine at TDC the cam caps would not go on and both cams were out by exactly the same amount (about 3 or 4 teeth) which means the belt had clearly slipped at the crankshaft pulley The (slightly) good news is that there is absolutely no evidence of either the exhaust cam pulley or crankshaft pulley having slipped on their shafts as pulley/engine block markings lined up perfectly so at least I won't have to worry about trying to take these off to check for what I though might have been a sheared woodruff key.
The timing belts were in perfect condition but I could see almost immediately that the white adjustable tensioner wasn't doing an awful lot and the 'pointer' on the spring-loaded mechanism was right on it's bottom stopper (even when the engine was turned in a forwards moving direction)...not good at all I can't believe there is any way the belt would have stretched by so much since it was fitted so as to cause the tensioner to do virtually nothing at all which means the finger of blame lies with the garage who did the head rebuild job 2K ago for not fitting the tensioner correctly It's an absolute miracle I managed to get 2K out of the engine before it trashed itself.
I decided to spent a couple of hours putting the belts back on and timing the car back up correctly (with the tensioner properly fitted this time) just in case, but sadly it was to no avail and the engine still ran like a bag on nails so there is obviously some valve damage somewhere and it was definately a head off job During removal of the head ancilaries, I came across numerous 'loose' bolts including some of the exhaust manifold ones!! I don't know what people this garage has (or had) working for them but they are clearly a bunch of incompetent amateurs
Anyway, the head is almost off but in true p**sy British weather style rain stopped play so hopefully it should be off tomorrow when I guess I will get to see the full extent of the damage
Shame you have no come back with the dodgy gararge... good luck with it all.
Does that mean you a runing around in the Evo?
Good to hear progress is being made. Its just a job of getting the head off and seeing what condition the valves and pistons are in.
Shall we take bets on the number of bent valves? My guess is 8
Head is off First inspection shows immediately that one exhaust valve is definately bent in cylinder 3 which is the cylinder I had suspected. With the cams off this is the only valve which doesn't go back into it's seat so maybe the others are all okay. Next I need to get the valve springs off to see which spin freely against their seats and which do not. This should then conclude how many valves need replacing. Pisons don't look too bad. A few dent obviously but some of theose were from the previous rebuild.
I will post up some pictures later.
Does anyone know the best way to de-coke the valves and exhaust chambers in the head?
Fingers crossed for a painless expereince... lets see some more snapz.
Good to hear it doesn't seem as bad as I was expecting, but like you say you need to get the valves out before you can really confirm it
As for de-coking I used acetone. Soak a rag in it and leave it down the bores for a few hours. After that the crap just wipes off the pistons. I got the head professionally cleaned when I had the valve seats cut.
How about doing the petrol test?
With the head upside down and the valves resting just pour some petrol into the top chambers.
If the petrol drains out your valves need reseating, if it doesn't they've obviously not touched anything and it's up to you to leave or pull apart.
It sounds like you're making rapid progress. Shame the weather's so on & off today.
All the non-damaged valves and all valve seats look in perfect condition but I will petrol test before everything goes back together just in case any do need regrinding.
I removed the springs, and every valve apart from the obviously bent exhaust one sit and spin perfectly ok in their seats, and there was no play in any of the valve guides whatsoever (which I didn't expect as these were all changed not so long ago anyway). I also took out all valves and spun them in an electric drill. All of the other 15 ran perfectly true so it seems I was lucky to get away with just one bent valve. It still boggles me though how just one valve became bent and all the others got away without any damage whatsoever How on earth did the other exhaust valve in the same cylinder survive???
Is it ok for me to replace just the ONE damaged valve or should I really replace both exhaust valves in that cylinder??
Anyway, a selection of piccies below. I will post up a full set once I've completed the job in a couple of weeks time.
Those are excellent pictures.
Was it that clean when it came off?
It looks like it won't be long before it is on the road again.
yeah great photos, thanks for sharing, it gives hope to the rest of use not brave enough to tackle a head job
It looks like its going to be quite a cheap rebuild Are you replacing the variator still?
edit: seen your other thread
I think you have coved every thing you need, but you don't need to replace the head bolts. As these are reuseable. there not strech bolts.
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