Dead cylinder for the first mile

[morsing]

Have you swapped injectors? I saw that you posted that you were going to, but didn't see a post that you had done the swap. Your symptoms are classic injector opening pressure, leaking, and/or really bad spray pattern. Good luck!

I swapped the cold-start injector, yes. It was leaking.

Pulled the #1 and #2 injectors yesterday, and attached little plastic bags to them. No leaking at all. Also previously checked the spray pattern which looked fine.

Could this be a vacuum leak? Time to get the propane torch out.

 

[morsing]

Air meter bellow is still soaked, I'm wondering if the new (refurbished) cold-start injector is leaking as well.

 

[tbrcktch]

Yes, I saw where you swapped out the cold start injector. But did you swap the #2 injector with another cylinder, to see if the misfire/dead cylinder followed the injector? Just swap #1 and #2 injectors. Just remove the 6mm bolts (10mm head), holding the injector housings. Pull the injector and housing out together (easier), and swap injector and housing together. Don't worry about the o'ring, for now. You should replace all the injector 0'rings, and the injector housing o'rings, but for now, just see if the dead cylinder follows the #2 injector. As to the bellows, take it off, and clean it, inside and out. Check to see if the bellows is split around the clamp area. Also pull the TV, and clean it out, and adjust to specs. If the bellows feels super squishy/slimy, it's probably oil soaked. Might want to replace it

 

[morsing]

I forgot I was planning to swap #1 & #2. I can easily just pull them from the housing. I checked the O-rings for leaks, they're tight.

 

[morsing]

Swapped #1 & #2 injector this morning, both fuel soaked, still #2 cylinder that didn't fire, so not a running problem with the injector.

Will leave them swapped over-night and if the dead-ness is on #1 in the morning, it's a leaking injector.

I have also taken the cold-start injector out and wrapped a little bag around it, I'm beginning to suspect the refurbished replacement is also leaking.

 

[morsing]

Cold-start injector not leaking. However, when I pull it out, there is oil in the hole. Also, the soaked air-flow meter bellow doesn't smell of fuel, so I'm beginning to think it might be oil from the oil-breather box? Could that be pushed into the inlet manifold after engine shut off? Not sure how that would happen.

 

[dl242gt]

It may be that the breather box isn't separating the oil and vapor so the combination makes it to the intake. The later kjet setup with the breather hose going into the air flow sensor dumps any oily residue right in there.

 

[morsing]

Started up again this morning with the injectors still swapped from yesterday, and it is still #2 that doesn't fire.

Could a blocked oil separator really cause this? The car doesn't burn oil and doesn't have any other issues.

I have noticed though, for some years, that I need to top up the coolant once or twice a year, this is why I did the head gasket test (see other thread). Not that I was super-confident in that testing.

 

[apollokid]

Have you tried to run the injectors manually with the engine turned off to check the spray pattern and the fuel delivery? (You can put a little plastic bottle under each injector, manually activate the pump and move the air meter plate with your hand)

If is not a fuel problem it could be that the spark plug is contaminated by water, fuel or oil and the electricity flows on the side of the plug and not jump the gap of the electrode until engine is hot.

Another possible cause is that a valve that doesn't seal perfectly when cold and you cannot diagnose it with a traditional manometer since it reads only the maximum pressure with a non return valve (for this type of failure a test with an in-cylinder pressure transducer is very powerful)

Check also for intake air leaks throught the manifold gasket by spraying LPG and see if the engine sound changes

 

[tbrcktch]

I think you can rule out injection, after your injector swap results. Do you have a spark plug tester (spark plug with ground clamp), and a remote starter cable? Try this cold: pull all plugs, connect remote starter, KEY OFF, position yourself so you can watch for any blow out of coolant from #2 cylinder, then activate remote starter to spin up motor (like if you were doing a compression test). Next, plug in spark plug tester to #2 plug wire and connect ground clamp to good ground, KEY ON, position yourself to see if the plug tester sparks, activate remote starter, and see if it sparks. Question: when the valve springs, and guide seals were replaced, was the head removed to do so?

 

[morsing]

Hi apollokid,

I think that is a little bit beyond what my toolset and skills can handle.

I don't have a spark plug tester, but I believe my timing gun would show the same. If I remember correctly from the early days, it was quite erratic, but that can also be due to a fouled plug. I will try this again for conclusive results.

I am still concerned about the injectors being soaked in fuel every morning. Are they really meant to have fuel up the sides?

I can do the cranking test looking for coolant, but I have also been considering getting a borescope. Not expensive these days.

The head was not removed to do the valve job. The coolant disappears so slowly, especially considering this is my daily driver, that I am a bit sceptical that would cause the problem. Compression is solid.

Regards,
Henrik Morsing

 

[apollokid]

Hi Henrik, also if I feel me much confident with LH systems than K-jets ones I don't agree with tbrcktch since swapping the injectors cannot tell you anything about the state of the fuel distributor. Also if is only an hypotesis, an uneven flux of fuel to the injectors could explain why you have a missfire in a specific cylinder.
That's why I suggest you to check the k-jetronic system running. Take a look at this video, but I suggest you to use 4 single bottle and not one big like he did

Regarding the timing gun I don't think that is a good tool to diagnose a fouled spark plug nor is good a spark tester (the light or the gap electrode tools that you put in series to the spark plug).

Es.
or


The problem with those tools is that in case of a fouled plug the electricity flows near normally into the HT leads but doesn't jump throught the electrodes and that's why the mixture doesn't ignite.
The only ways that I know to detect a fouled spark plug is to change it with a new one or to check the secondary signal with an automotive scope but unfortunately only a few people have one and are able to use it.
After having verified that is not a wiring problem and the plug makes the arc I suggest you to make this simple test: remove all the spark plugs and the fuel pump fuse, crank the engine for a few seconds to clean all the combustion chambers, install a new spark plug on the faulty cylinder and reinstall the other plugs, reinstall also the fuse and crank the engine. If the problem is no more present it could be due to something that prevents the spark plug to do its job (water, fuel or oil).

Finally, compression could only be one of the causes but it doesn't means that is the cause.
It must be checked anyway.

You say that it is solid but I'm generally a bit skeptical in checking compression with standard manometers since I think that it must not be so difficult to reach acceptable maximum values by letting the piston to compress the air many times throught a one way valve.
In the past I remeber some professional compression tools that were able to trace the pressure on charts when the engine is cranking so that it was possibile to see how fast the pressure grows up and not only to get a maximum value.

Es.

I don't think that you are using a tool like this one but may be I'm wrong. In this case I'm sorry.

Diego

 

[tbrcktch]

If you look at my post, I recommended pulling the injector, with the housing, and just swapping out the #1, and #2 injectors, with housings still on, and still attached to the injector line. That would be an effective test of both the injector, and the fuel distributor, if the misfire remains with #2 cylinder. Also regarding the plug tester, wasn't talking about using either of your examples. I described the style using a spark plug with clamp attached to the metal base that you ground at the engine, which will fire across an electrode gap, because it is a spark plug. You will be able to see a spark if it is firing.

Hi Henrik, also if I feel me much confident with LH systems than K-jets ones I don't agree with tbrcktch since swapping the injectors cannot tell you anything about the state of the fuel distributor. Also if is only an hypotesis, an uneven flux of fuel to the injectors could explain why you have a missfire in a specific cylinder.
That's why I suggest you to check the k-jetronic system running. Take a look at this video, but I suggest you to use 4 single bottle and not one big like he did

Regarding the timing gun I don't think that is a good tool to diagnose a fouled spark plug nor is good a spark tester (the light or the gap electrode tools that you put in series to the spark plug).

Es.
View attachment 23081 or View attachment 23082


The problem with those tools is that in case of a fouled plug the electricity flows near normally into the HT leads but doesn't jump throught the electrodes and that's why the mixture doesn't ignite.
The only ways that I know to detect a fouled spark plug is to change it with a new one or to check the secondary signal with an automotive scope but unfortunately only a few people have one and are able to use it.
After having verified that is not a wiring problem and the plug makes the arc I suggest you to make this simple test: remove all the spark plugs and the fuel pump fuse, crank the engine for a few seconds to clean all the combustion chambers, install a new spark plug on the faulty cylinder and reinstall the other plugs, reinstall also the fuse and crank the engine. If the problem is no more present it could be due to something that prevents the spark plug to do its job (water, fuel or oil).

Finally, compression could only be one of the causes but it doesn't means that is the cause.
It must be checked anyway.

You say that it is solid but I'm generally a bit skeptical in checking compression with standard manometers since I think that it must not be so difficult to reach acceptable maximum values by letting the piston to compress the air many times throught a one way valve.
In the past I remeber some professional compression tools that were able to trace the pressure on charts when the engine is cranking so that it was possibile to see how fast the pressure grows up and not only to get a maximum value.

Es.

I don't think that you are using a tool like this one but may be I'm wrong. In this case I'm sorry.

Diego

 

[tbrcktch]

There is a possibility that you might have carbon build up on your valves on #2 cylinder. If you have enough build up, it can cause, usually, cold start misfiring. It acts like a charcoal briquette, and just sucks up the fuel, which is a bigger issue when starting up, and running cold. Once warmed up it isn't so detrimental, as you don't need as much fuel, as during cold start. That could explain your issue. Check by pulling the intake manifold, look down the intake ports. If that's the problem, you should be able see the build up.

 

[apollokid]

If you look at my post, I recommended pulling the injector, with the housing, and just swapping out the #1, and #2 injectors, with housings still on, and still attached to the injector line. That would be an effective test of both the injector, and the fuel distributor, if the misfire remains with #2 cylinder.

You are right, sorry.

Also regarding the plug tester, wasn't talking about using either of your examples. I described the style using a spark plug with clamp attached to the metal base that you ground at the engine, which will fire across an electrode gap, because it is a spark plug. You will be able to see a spark if it is firing.

Firing outside of the combustion chamber is not the same as inside since the pressure is different.
It is still a good test to check that leads are not broken.

 

[tbrcktch]

No worries, was just clarifying. Sometimes, we just have to do alot of testing, during our diagnosis, that may not in of itself, tell us the answer, but will help us weed out the things that were a possibility. Then we can really focus on what is left, and how we can finish solving the riddle, eh?

 

[apollokid]

No worries, was just clarifying. Sometimes, we just have to do alot of testing, during our diagnosis, that may not in of itself, tell us the answer, but will help us weed out the things that were a possibility. Then we can really focus on what is left, and how we can finish solving the riddle, eh?

Sure, that's why it is very import that a test is as much accurate as possibile since if we conclude that a compontent is ok when it is not the solution of the enigma will never be found and all the diagnostic process will fail.

Moving injectors with the hose attached was a really good idea, much smarter than mine since if the missfire doesn't follow the injector we can exclude at 100% also the fuel distributor (Furthermore also if the distributor or the injector spray pattern wasn't fine we can exclude it anyway for this problem).
I was thinking that only the injector was moved (like we generally do in EFI systems), may be due to a misunderstand of what you had originally written.
If this test was already done a fuel problem can be excluded and it remains only ignition or mechanical.

 

[tbrcktch]

Yup

 

[morsing]

Apologies for going quiet, have been away on family business.

I bought an inspection camera, and very briefly checked cylinder 1 & 2. Both looked to have burnt oil on the top. Didn't look at the valves.

I have a problem, as the engine and transmission are always soaked in oil, and I'm pretty sure I need to have a look at the oil separator box.

I replaced it some years ago, and I have had the oil and dead cylinder problem for some years as well. I just looked at some info about working on the separator, and it said to be careful with some tube that going into the block. as it needs to sit at the right height. I had never heard of that! Could that be my problem?

Regards,
Henrik Morsing

 

[apollokid]

This is the top of the pistons in the 940 B200FT that my dad had bought last year, may be that the seals of the valves are a bit worn but the engine runs fine and doesn't smoke. The car have 330.000km mostly drived with LPG instead of gasoline.
It is much different from yours?

I don't think a clogged blow-by recirculation system could give you those symtomps, generally the first syntomps are oil leaks from seals due to the increased pressure inside the block or the oil dip stick that jumps out of its tube.