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dead cylinder

Been trying to find the cause of my misfire in my Carrera and today I went to another trusted mechanic I know who had time to check my car. He pulled number 1 plug wire and sure enough there was no change the way that the motor ran. Pull the other plugs and the rpm's go down. He did the dollar bill test and it showed that my exhaust was sucking as well and blowing out. He then checked my new number 1 injector and it was clicking fine. I also have spark. Valves have been adjusted so I am very bummed because I feel something is very wrong with the number 1 valves. Just not a good Wednesday.
Old 05-16-2018, 09:23 AM
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Let it cool off and jack it up on the drivers side and pull the valve cover checking the valve adjustment. Shouldn’t have any oil running out
Bruce

Last edited by Flat6pac; 05-18-2018 at 03:38 AM..
Old 05-16-2018, 09:26 AM
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Nick -- While you confirmed that the injector's clicking, did you pull the injector to confirm that it's squirting fuel? Clicking (as I understand it) means it's shutting off fuel flow at each click. Finally, you indicate that you "also have spark" -- did you pull the plug for the offending cylinder, ground it and confirm spark? Want to be sure you have both spark and fuel going to that cylinder.

Finally, if the above all pan out (you confirm that cylinder 1 is indeed getting both spark and fuel), you should have a leakdown/compression test done on that cylinder (as lack of compression/abnormal leakdown would confirm that something's amiss with that cylinder).

Confused by the dollar bill check, as it sounds like it was done on the tailpipe and would therefore be reflecting overall running condition of engine, not stuff specific to cylinder #1?
Old 05-16-2018, 09:31 AM
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Dollar bill test shows that the overall conditions of motor are bad. Shows sucking in Old school trick. Car has good spark. I’ll check valve clearance again on cylinder number 1.
Old 05-16-2018, 10:41 AM
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I just pulled plug wire again and still no change Running on 5 cylinders.
Old 05-16-2018, 10:43 AM
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Have you run a compression of leak-down test on your engine? If not that would be a good place to start. If you have a serious valve issue it should be readily evident with a compression test.

Also, just a suggestion, but it might be best to keep your troubleshooting and question to a single thread. I believe you have at least 3 or 4 thread all pertaining to this same problem, so the information is scattered, as far as what you've done and testing you've performed. Pick one thread and continue with it, and possibly refer the old threads to the one you want to use.
Old 05-16-2018, 10:44 AM
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Quote:
Originally Posted by darrin View Post
Nick -- While you confirmed that the injector's clicking, did you pull the injector to confirm that it's squirting fuel? Clicking (as I understand it) means it's shutting off fuel flow at each click. Finally, you indicate that you "also have spark" -- did you pull the plug for the offending cylinder, ground it and confirm spark? Want to be sure you have both spark and fuel going to that cylinder.
Nick, have you done this? Is the plug bad? Injector clicking but not squirting? It appears they are OK but are they?
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Old 05-16-2018, 10:53 AM
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Injector squirting , has 12 volts going to injector. Have good spark . Checked valves twice already. Will check again. Fresh oil and tuneup. Pull number 1 plug wire, no change . Car will soon be a very pretty planter full of Daisies and philodendrons.
Old 05-16-2018, 10:59 AM
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Sorry about all the threads. I did fix some of the stuff on old threads like the cold startup and rough idle. The new intake gaskets fixed those.
Old 05-16-2018, 11:02 AM
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Quote:
Originally Posted by Nick Triesch View Post
Sorry about all the threads. I did fix some of the stuff on old threads like the cold startup and rough idle. The new intake gaskets fixed those.
Compression test.
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Old 05-16-2018, 11:38 AM
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compression test.... shoulda done it first
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Old 05-16-2018, 11:45 AM
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Outside shot, but I had a mechanic diagnose a dead cylinder on my car recently. Ended up being the spark plug wire had somehow managed to unscrew from the spark plug boot (Beru.)

Car was fine when I dropped it off, but sure did idle lumpy when I picked it up.

Fortunately took me 2 minutes to diagnose and 10 more to fix.

Not going back to that mechanic.
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Old 05-16-2018, 11:55 AM
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Originally Posted by 76FJ55 View Post
Have you run a compression of leak-down test on your engine? If not that would be a good place to start. If you have a serious valve issue it should be readily evident with a compression test.

Also, just a suggestion, but it might be best to keep your troubleshooting and question to a single thread. I believe you have at least 3 or 4 thread all pertaining to this same problem, so the information is scattered, as far as what you've done and testing you've performed. Pick one thread and continue with it, and possibly refer the old threads to the one you want to use.
Absolutely.

Did the car ever run well after the OP adjusted the valves ? Hard to tell with the dozen threads on this.
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Old 05-16-2018, 12:04 PM
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If the dollar bill test is accurate, it sounds like you have a burnt exhaust valve. No need to do a leak down test, a cheap compression tester with a screw on hose will do the job. If you do a leak down, it would show if the leak in at a valve or at the rings.

If an exhaust valve was adjusted too tight, you can burn a significant hole in it. There are worse things, just not if you were wanting to go for a quick drive. If you keep driving it and drop a valve, that is when things get super expensive.
Old 05-16-2018, 12:21 PM
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Quote:
Originally Posted by 76FJ55 View Post
Also, just a suggestion, but it might be best to keep your troubleshooting and question to a single thread. I believe you have at least 3 or 4 thread all pertaining to this same problem, so the information is scattered, as far as what you've done and testing you've performed. Pick one thread and continue with it, and possibly refer the old threads to the one you want to use.
Agreed, and it's closer to 12.
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Old 05-16-2018, 01:01 PM
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wow i figure at least 8 suggestions to check the compression already ... and ???
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Old 05-16-2018, 01:01 PM
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Ok, I did compression check. 5 cylinders at right about 150, Number one at 140. Also took valve covers off of intake and exhaust valves. both intake and exhaust number one have movement and I adjusted them correctly . After everything, still no change when I remove number 1 spark plug. Still have misfire throughout the entire range. I have done everything that I can do. Even Techron. Stumped also I know I have low compression numbers but car has 157,000 miles on th clock. It should still fire. The
Old 05-17-2018, 04:49 PM
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Quote:
Originally Posted by Nick Triesch View Post
Sorry about all the threads. I did fix some of the stuff on old threads like the cold startup and rough idle. The new intake gaskets fixed those.
When replacing the intake gaskets, if you did not retighten the manifold correctly, you will end up with a dead cylinder even though you have spark, fuel, and compression. Check those nuts again.
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Old 05-17-2018, 07:24 PM
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I only replaced the gaskets on the passenger side . The drivers side where cylinder number one is did not leak . So if I have fuel, spark and valve movement and compression, Maybe it is the ECU or the dme relay.
Old 05-17-2018, 09:14 PM
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, not likely to be dme or relay I would think. Doesn't the DME just fire all injectors at the same time and provide spark, it does not discriminate cylinders is my understanding.

I know it sounds odd but did you check , cap rotor and wires ?

as this is still not fixed maybe we need to go back to basics, did you use a new plug to check spark against a ground , and then install that actual plug in the engine ?
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Last edited by theiceman; 05-18-2018 at 05:17 AM..
Old 05-18-2018, 05:15 AM
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