What could be wrong?

syncview

Well-Known Member
Joined
Oct 11, 2007
Messages
1,136
Location
Lahore, Pakistan.
Car(s)
Suzuki Alto...yayyy!
When idling or at constant revs, my car sort of BURPS... you can see the watery bubbles out of the exhaust pipe when its started in the morning.. and it feels like it misses after some intervals can hear the engine sound change for a second or less and at the same moment the bubbles can be seen... everything like spark plugs, breaker point, plug wires are fine, had them recently installed.. Spark plugs are bosch's four tip plugs (new for the car)never used these before .. note that i dont feel this missing while driving.. could this be the distributor?


and sometimes the starter motor stops when starting, and then goes fine.. had the starter motor done, new bushes etc.. and had a new battery installed.. so i dont think that starter motor or the battery is the problem... would this problem be related in anyway to the clutch or pressure plates? :?


i sound like an idiot, but i dont know the exact words for/about what i'm trying to say :S
 
Are we talking actual bubbles, or just liquid? Secondly, is it actually water (a sign of good combustion) or gasoline (you're running much too rich and not burning it properly).
 
There are physical bubbles coming out of the exhaust? Does this persist when the engine is warmed up? Finally, does the exhaust smell sweet when you see the bubbles? If so, it's coolant.

A poor idle, and water being where it shouldn't be seems to me like a head gasket issue where the cylinder and coolant are now linked. If water dribbles into the cylinder when the car is off, it would make it somewhat hard to start occassionally, and be rough idling if the compression has dropped significantly. Once moving though, the car should seem normal, maybe with a slight ticking sound (similar to a leaky exhaust manifold).

Have you ever noticed a release of smoke or excess internal pressure when removing the cap from your coolant expansion tank? If water is getting into a cylinder, gas should be getting out.

Running a compression test should give you a definitive answer. Testers are fairly cheap, and all you have to do is remove the spark plugs, hook it up, and give the engine a few cranks. If there is a problem, my bet is that one cylinder will be very low (sub 100psi), and another one will probably be a little low.
 
It may help to know what sort of car: make, model, engine, and year. How has the weather changed since this started happening? Any rain?

Also, it is common for water to come out of the exhaust when you first start an engine. This will happen in the mornings after being driven the day before or if it has at least a few hours to cool off. This is completely natural and is just condensation from the exhaust cooling off. It will disappear soon after warming up. If it does smell sweet, that is a problem though.

Secondly, you mention that you recently had the car tuned up. So the first thing I would check is to make sure that all of the wires are on correctly, ie. the metal piece should be on the spark plug terminal, and the boot should be snuged down on the ceramic insulator. Also make sure that the plug wires are correctly installed on the distributor cap. You may have also damaged the wires, this ussually happens at the spark-plug end.

http://en.wikipedia.org/wiki/Spark_plug#Parts_of_the_plug


If this all checks out you may have carbon tracks in the distributor cap. They will look like a river does on a map, on the inside of your cap.

If you do have a blown headgasket there are a couple of things that give it away. First check to see if you have any coolant loss. It can be a small amount at first so note any drop (you will see it in the expansion/overflow tank first). You may also notice that it isn't producing heat as well as before.

If you notice either of these the best test is a compression test. It is easy enough to do, and is easy to diagnos exactly what is wrong inside the engine.



Be catious when looking into the radiator, it can sometimes "burp" when the thermosat first opens.

But, there is an alternative. With the car cold, take the cap off of the radiator (put the cap where it won't fall into moving bits) and then start the car and let it warm up. You may see bubbles in the coolant escaping if it is a head gasket. They will be small, like in a fish tank.
 
Hmm.

If there's pressure building up to create sudden air flow (and therefore creating bubbles) then this sounds like maybe a sticking valve problem. This would cause pressure to build up in the cylinder, which would be released causing a bubble, and would also cause the engine to lock on the compression stroke, hence the motor stopping.

That's my theory anyway, I don't claim to be an engine expert. :)
 
Damn it QUICK REPLY! :(


Thank you to all of you, will check everything mentioned next morning and will tell you guys..

its a suzuki alto, 3 cylinder 800cc on CNG.. has done 74000 Kilometers, 71000 being on CNG and 3000 on petrol.

I had written a VERY detailed reply, but dammit.. my mistake, didnt copy it before submitting. I will check all that tomorrow morning and will tell you guys.
it does sound like a leaky exhaust.. doesnt heat up aswell (but this might be due to the weather change, as now we dont need A/Cs in homes.. but do need them in the car though.) The bubbles just show up at the end of the exhaust pipe and vanish.. I will check all things mentioned by Cubits and GRtak... and will tell you guys..

Thanks!
 
Ok guys..

did a check today in the morning, there were no bubbles :?

but it still misses.. and i can hear w/e it is called from the exhaust pipe when it misses.. there was water but no bubbles.. I think the headgasket is fine, there were no bubbles in the radiator.. no oil in the radiator..would the bubbles be due to the rain?

now i didnt understand that coolant loss? it drops coolant when driven for like 2 to 3 hours.. and then parked in the garage, after sometime we can see 2 to three drops of coolant..


and got that exhaust checked, its fine, the whistling sound is coming from the generator pulley's bearings...


Would it miss because of the spark plugs? If it is because of the spark plugs, how can i check that?
 
Would it miss because of the spark plugs? If it is because of the spark plugs, how can i check that?

Change them. Unless you want to hold one in your hand and crank the engine (with the others removed) and watch for the spark. If you're using different sparks than before you should really get a new set of the 'old' ones.

Coolant loss is strange, have you checked the expansion tank lid? The radiator bottom hose? It's coming from somewhere. Might just be a pipe on the engine block itself. My Series III sprays oil out of a breather pipe, took me a while to work out where the black was coming from.

Anyway I think the missing sound is because your fourth cylinder has escaped.
 
Ok guys..

did a check today in the morning, there were no bubbles :?

but it still misses.. and i can hear w/e it is called from the exhaust pipe when it misses.. there was water but no bubbles.. I think the headgasket is fine, there were no bubbles in the radiator.. no oil in the radiator..would the bubbles be due to the rain?

now i didnt understand that coolant loss? it drops coolant when driven for like 2 to 3 hours.. and then parked in the garage, after sometime we can see 2 to three drops of coolant..


and got that exhaust checked, its fine, the whistling sound is coming from the generator pulley's bearings...


Would it miss because of the spark plugs? If it is because of the spark plugs, how can i check that?

If you are losing coolant and the exaust is bubbling, you could have a cracked block/or leaking gasket somehwere and coolant is escaping from the water jackets into the cumbustion chamber.
 
You need to find your coolant leak. It sounds like it may be a pinhole leak that can be hard to locate. If the pinhole leak is in the right spot, it can spray onto your plugs/ wires, distributor, or even into the air inlet which can cause a miss. How much is the coolant down? And are you filling it back up? A small coolant leak can lead to a big problem like: Blown headgasket, cracked head or block, scorched cylinder walls, so make sure you keep it filled up.

You also mentioned a noise from the generator, are you sure the noise is from the generator and not the water pump? Water pumps can make noises when they are failing and leak small amounts of coolant at the same time.

Maybe it is time to get someone with some experience to help out locally. Basic experience is a big help. And it is hard to diagnos a problem with out being there to check it out.
 
Yes, its from the generator, the bearings need to be replaced.. got it checked from the mechanic. it leaks the coolant under the coolant bottle.. i mean its under where the bottle is placed. it comes out from the bottle. The bottle needs to be filled up till half, i checked the coolant in radiator..its up to the level. and there were no bubbles when i start it in the morning.

I will do the spark plugs test tomorrow. But, what i can say is, by using these bosch's four tip plugs, mileage has significantly increased, from 11 to 12 kilometers a liter its gone upto 14 to 15 kilometers per liter.

and on CNG on one tank it used to do around 95 kilometers with a/c and now it does around 120-125 with A/C..
 
Top