This problem has me really baffled. The engine miss just recently started. I replaced the head and flywheel [flexplate] about a year ago. I replaced the plugs. The problem has been determine to be with the number 3 cylinder. There is no change at all when removing the #3 spark plug wire while the engine is running. The resistance for #3 injector is within tolerance at 16 ohms. The voltage at the connector is good at 14vdc. Removing the connector at the #3 injector changes nothing. I swapped #2 injector with #3 and #3 works fine in #2 position. #3 injector ok. The spark at #3 wire and spark plug tip is great. I even swapped plug wires to eliminate the possibility of a faulty wire. Nothing that i did changed or move the problem associated with cylinder #3. I failed to mention that I also replaced the timing belt last year. Is it possible that the spark is not being delivered at the correct time to the #3 cylinder? If so, what faulty sensor, etc. could cause this? I have the Haynes manual. Any help greatly appreciated.
1999 Escort 2.0 SOHC Missing at idle and low speedT
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Just what I was afraid of!!!!!!!!!!!!!!
I did a compresion test. Cylinder #1 [155 - 160], Cylinder #2 [160 - 165], Cylinder #4 [180], oh and yeah Cylinder #3 [10]. #1 & #2 readings increased by about 20 when I squirted a few drops of motor oil in the cylinder. #4 stay at 180 after the oil. #3 didn't change. I plan to pull the head even though it was just replaced last year and hope that it is a valve problem with #3. The engine did'nt seem burn much oil with 150K plus miles and it didn't smoke. No noticble engine noise either. Compression for the other 3 cylinders is not great but ok I guess. The problem happen without any warning. Even now, I can hardly tell that I have a problem except at idle......strange. Any suggestion fellow Escort owners?
Thanks
I did a compresion test. Cylinder #1 [155 - 160], Cylinder #2 [160 - 165], Cylinder #4 [180], oh and yeah Cylinder #3 [10]. #1 & #2 readings increased by about 20 when I squirted a few drops of motor oil in the cylinder. #4 stay at 180 after the oil. #3 didn't change. I plan to pull the head even though it was just replaced last year and hope that it is a valve problem with #3. The engine did'nt seem burn much oil with 150K plus miles and it didn't smoke. No noticble engine noise either. Compression for the other 3 cylinders is not great but ok I guess. The problem happen without any warning. Even now, I can hardly tell that I have a problem except at idle......strange. Any suggestion fellow Escort owners?
Thanks
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If the head valves on #3 happen to be good then the piston rings seized and broke. Also what can be done is remove the intake and exhaust manifold, and remove the crankcase and splash guard.
Place the piston on BDC on compression stroke and fill with oil slowly compress the oil and check the intake side and exhaust side and the bottom of the piston look where the oil is going out.
The oil should not go out from any place but if it does you found where its coming from.
Place the piston on BDC on compression stroke and fill with oil slowly compress the oil and check the intake side and exhaust side and the bottom of the piston look where the oil is going out.
The oil should not go out from any place but if it does you found where its coming from.
I just had this happen to my 97 Escort in late July. The #4 intake valve seat on the replacement rebuilt head came loose without prior warning after only 16 months in service. Fortunately, it didn't disintegrate and damage the piston.
Check the #3 intake valve seat carefully to see if it sits higher than the other three (it should be flush with the surface of the surrounding head like the other 3).
Check the #3 intake valve seat carefully to see if it sits higher than the other three (it should be flush with the surface of the surrounding head like the other 3).
I pulled the head today. the top of the pistons and cylinder walls look good ---no broken metal that i can see. The pistons go up and down like they are suppose to. No stuck valves for #3. I need to get a valve spring compressor tomorrow to remove #3 valves for a detailed inspection but the valves fully close and open like they are suppose to. Now the head gasket may be a suspect. It looks a little strange where it mate wit #3. There is a small raised area on the gasket where a leak could be possible but I don,t know if it would cause the low compression that I am reading on #3. Hopefully I should no a little more tomorrow. What do you guys think about the head gasket?
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461 Posts
Not necessarily if only one ring broke it will lose almost all compression but not burn oil heavily. For that the two top rings must not exist or be heavily damaged, worn.docwr1234 said:
update
I replaced the head gasket and remove #3 exhaust and intake valves for inspection. The intake had a heavy buildup of hard carbon deposit in one area of the valve but didn't seem to interfere with the seating of the valve. I cleaned both valves and reinstall. I reinstalled the head and put every thing back together. Started the engine and ....... same old problem on #3. I guess it has to be the compression rings. Time to pull the engine/tranny combo....never done that before. It looks pretty straight forward in the Haynes manual. If i get that far, I plan to do a complete overhaul. Question, if the cylinder walls look good, do I still need to rehone them or have them machined to slightly larger size pistons/rings? Still debating the options [1] rebuild the engine, [2] install a use engine from the salvage yard, [3] install a recondition short block. Any suggestions for a first timer? BTW, I checked all of the local salvage yards and no one has a used engine that will fit the scort.
Thanks
I replaced the head gasket and remove #3 exhaust and intake valves for inspection. The intake had a heavy buildup of hard carbon deposit in one area of the valve but didn't seem to interfere with the seating of the valve. I cleaned both valves and reinstall. I reinstalled the head and put every thing back together. Started the engine and ....... same old problem on #3. I guess it has to be the compression rings. Time to pull the engine/tranny combo....never done that before. It looks pretty straight forward in the Haynes manual. If i get that far, I plan to do a complete overhaul. Question, if the cylinder walls look good, do I still need to rehone them or have them machined to slightly larger size pistons/rings? Still debating the options [1] rebuild the engine, [2] install a use engine from the salvage yard, [3] install a recondition short block. Any suggestions for a first timer? BTW, I checked all of the local salvage yards and no one has a used engine that will fit the scort.
Thanks
Why guess? It would be much simpler to swing the cat conv out of the way, remove the oil pan and baffle, disconnect the rod and remove the #3 piston to see what's going on. I'd hate to pull the engine/tranny only to find nothing wrong with #3.
If there's nothing wrong with the #3 cylinder, just hone it a little to break the glaze.
The proper way to test #3 when you found no compression is to do a cylinder leakdown test. Normally you'd use a gauge to measure flow, but in this case, just apply shop air thru the spark plug hole (using an adapter) with the valves closed and see where it's leaking out of (intake, exhaust or oil cap). At this point, it's probably easier to remove the oil pan than to put the head back on with the old gasket.
If the engine was running ok except for this problem, a complete overhaul might be a bit much at this point.
If there's nothing wrong with the #3 cylinder, just hone it a little to break the glaze.
The proper way to test #3 when you found no compression is to do a cylinder leakdown test. Normally you'd use a gauge to measure flow, but in this case, just apply shop air thru the spark plug hole (using an adapter) with the valves closed and see where it's leaking out of (intake, exhaust or oil cap). At this point, it's probably easier to remove the oil pan than to put the head back on with the old gasket.
If the engine was running ok except for this problem, a complete overhaul might be a bit much at this point.
I was thinking overhaul because the problem has been narrowed down to a failure of some sort within the #3 cylinder. The head /valves/ gasket has all but been eliminated as a cause of the very low compression. Compression in # 1 and 2 cylinder improved significantly after squirting a few drops of oil in the spark plug hole before compression test. Cylinder #4 remained at 80+ even after the oil. The engine has over 150K. My guess is IF the rings failed in #3, the rings for the remaining cylinder are probably not far behind from failing. I would love to just have to pull the oil pan, pull #3 piston, replace the rings, hone the cylinder a bit and be done with it. Has any one out there had any long term success in doing this procedure? I don't want to have to replace the engine if I can help it.
Question for "rbailin" if nothing is wrong with the piston/rings in cylinder #3, what would be the purpose of honing the cylinder to remove the surface glaze? Also, the head has already been reinstalled with a new gasket. Can I get by without pulling the head again to pull the cylinder?
Thanks
Question for "rbailin" if nothing is wrong with the piston/rings in cylinder #3, what would be the purpose of honing the cylinder to remove the surface glaze? Also, the head has already been reinstalled with a new gasket. Can I get by without pulling the head again to pull the cylinder?
Thanks
What I was trying to say was that if there's nothing wrong with the #3 cylinder and you had to replace the rings, you could get away with just honing the cylinder to help seat the new rings.
It may be possible to remove a piston from the bottom, but with the crankshaft in the way, and the likely ridge at the bottom of piston travel, it would be difficult indeed. And you'd have to pull the head to install the piston anyways.
I didn't realize you had problems with the other cylinders as well. Since you already put the head back on, why not do a quick leakdown test if you have access to an air supply of about 100 psi.
You can buy a hose-to-spark plug adapter at most auto parts stores. You can do without an actual leakdown gauge for now. Loosen all the rocker arm holddown bolts to allow the valves to close completely. Replace the valve cover. Screw the adapter into each spark plug hole, apply 100 psi air, and listen for leaks. Usually the test is done with the piston at TDC, but since your looking for a major leak, it doesn't really matter.
If the air is coming out of the intake/throttle body, your intake valve is leaking. If out of the exhaust, it's your exhaust valve. And if it's out of the valve cover or dipstick tube, it's the rings. Note that you'll always get a small amount of leakage past the rings, but we're looking for a large leak here on #3. Note that there's a 4th possibility of leaking past the head gasket into coolant, oil, or another cylinder, but with the new head gasket that's unlikely.
It may be possible to remove a piston from the bottom, but with the crankshaft in the way, and the likely ridge at the bottom of piston travel, it would be difficult indeed. And you'd have to pull the head to install the piston anyways.
I didn't realize you had problems with the other cylinders as well. Since you already put the head back on, why not do a quick leakdown test if you have access to an air supply of about 100 psi.
You can buy a hose-to-spark plug adapter at most auto parts stores. You can do without an actual leakdown gauge for now. Loosen all the rocker arm holddown bolts to allow the valves to close completely. Replace the valve cover. Screw the adapter into each spark plug hole, apply 100 psi air, and listen for leaks. Usually the test is done with the piston at TDC, but since your looking for a major leak, it doesn't really matter.
If the air is coming out of the intake/throttle body, your intake valve is leaking. If out of the exhaust, it's your exhaust valve. And if it's out of the valve cover or dipstick tube, it's the rings. Note that you'll always get a small amount of leakage past the rings, but we're looking for a large leak here on #3. Note that there's a 4th possibility of leaking past the head gasket into coolant, oil, or another cylinder, but with the new head gasket that's unlikely.
leak down test done
rbailin, I performed the leak down test yesterday evening. I loosen all of the rocker arms to seat all of the valves and replaced the valve cover. I only have a small compressor but it does build up to 180 psi. #1, 2, and 4 were ok. #3, the air leaked out rapidly. I had a difficult time trying to determine where the air was leaking from. It sounds like it's near the exhaust manifold. The air supply doesn't last long enough for me to really determine. I am thinking that maybe it's rushing past the rings and sounds like it at the exhaust manifold. I removed the valve cover and repeated the test while slowly tighten and opening the bolt for the rocker arm for the exhaust valve and I could hear the difference in the air flow at the maniflod. No air is coming from the dipstick tube or the valve cover. Question: if the air is leaking past the rings, should I be able to pull the dipstick and see where the air forced the oil level rise on the dipstick? Also, can I just remove the exhaust manifold to really verify that it is leaking from the exhaust.
Thanks
rbailin, I performed the leak down test yesterday evening. I loosen all of the rocker arms to seat all of the valves and replaced the valve cover. I only have a small compressor but it does build up to 180 psi. #1, 2, and 4 were ok. #3, the air leaked out rapidly. I had a difficult time trying to determine where the air was leaking from. It sounds like it's near the exhaust manifold. The air supply doesn't last long enough for me to really determine. I am thinking that maybe it's rushing past the rings and sounds like it at the exhaust manifold. I removed the valve cover and repeated the test while slowly tighten and opening the bolt for the rocker arm for the exhaust valve and I could hear the difference in the air flow at the maniflod. No air is coming from the dipstick tube or the valve cover. Question: if the air is leaking past the rings, should I be able to pull the dipstick and see where the air forced the oil level rise on the dipstick? Also, can I just remove the exhaust manifold to really verify that it is leaking from the exhaust.
Thanks
Sure you could remove the exhaust manifold and check for a strong breeze coming from the #3 port. You could also probably get away with just disconnecting the cat conv pipe and checking for airflow there if that's easier, but removing the manifold will eliminate all doubt.
In any case, doing either of these will definitely prove whether it's the valve or the rings.
In any case, doing either of these will definitely prove whether it's the valve or the rings.
Hey rbailin, I pulled the exhaust manifold and performed the leak test on #3. Air rushed out of the exhaust port. I don't know if this is good or bad news. All I can think now is that I have a large crack or hole in the head at the exhaust port. I stuck my finger in the port and could feel the air near the valve stem. The valves seated fine when the head was removed. I also replaced the seals for the 2 valves. I plan to finish removing the head tomorrow and throughly examine it. At least I don't have to replace the rings right now. Do you have any more advice?
Thanks for the help
Thanks for the help
If you have the patience, remove the head and swap the #3 & #4 exhaust valves, put it back together with the same gasket and test again. If you have a tube of Prussian Blue, you can use it to check how the valve is sealing. Or, just bring the head to a machine shop and let them test it for cracks and leaks.
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