no compression in number 7 cylinder intermittent
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no compression in number 7 cylinder intermittent
here a strange problem.
i had a mechanic change my starter on my 92 sc400.
a week later the car runs on 7 cylinders,. the mechanic finds i have no compression in cylinder 7. I take it to the lexus dealer who does a compression and leak down test to find the same, no compression.
i take the car and it limps home. the next day i start it and it runs on all 8 cylinders, i did not do a compression check but i could tell, i drive it for awhile like about an hour and then it starts running on 7 cylinders again.
the car is possessed. i heard it could be carbon build up on an intake valve, so i ran some water through a vacuum hose to get rid of carbon. old school trick i guess, but, it ran good and then came back.
any ideas, its driving me crazy.
how could a cylinder have no compression then work fine.
all ideas appreciated
thanks
i had a mechanic change my starter on my 92 sc400.
a week later the car runs on 7 cylinders,. the mechanic finds i have no compression in cylinder 7. I take it to the lexus dealer who does a compression and leak down test to find the same, no compression.
i take the car and it limps home. the next day i start it and it runs on all 8 cylinders, i did not do a compression check but i could tell, i drive it for awhile like about an hour and then it starts running on 7 cylinders again.
the car is possessed. i heard it could be carbon build up on an intake valve, so i ran some water through a vacuum hose to get rid of carbon. old school trick i guess, but, it ran good and then came back.
any ideas, its driving me crazy.
how could a cylinder have no compression then work fine.
all ideas appreciated
thanks
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here a strange problem.
i had a mechanic change my starter on my 92 sc400.
a week later the car runs on 7 cylinders,. the mechanic finds i have no compression in cylinder 7. I take it to the lexus dealer who does a compression and leak down test to find the same, no compression.
i take the car and it limps home. the next day i start it and it runs on all 8 cylinders, i did not do a compression check but i could tell, i drive it for awhile like about an hour and then it starts running on 7 cylinders again.
the car is possessed. i heard it could be carbon build up on an intake valve, so i ran some water through a vacuum hose to get rid of carbon. old school trick i guess, but, it ran good and then came back.
any ideas, its driving me crazy.
how could a cylinder have no compression then work fine.
all ideas appreciated
thanks
i had a mechanic change my starter on my 92 sc400.
a week later the car runs on 7 cylinders,. the mechanic finds i have no compression in cylinder 7. I take it to the lexus dealer who does a compression and leak down test to find the same, no compression.
i take the car and it limps home. the next day i start it and it runs on all 8 cylinders, i did not do a compression check but i could tell, i drive it for awhile like about an hour and then it starts running on 7 cylinders again.
the car is possessed. i heard it could be carbon build up on an intake valve, so i ran some water through a vacuum hose to get rid of carbon. old school trick i guess, but, it ran good and then came back.
any ideas, its driving me crazy.
how could a cylinder have no compression then work fine.
all ideas appreciated
thanks
lol do this ok!
start the engine, unplug the injectors one by one and see if the idle changes!
do same on the spark plug unplug the wires going to them one by one and se if the idle changes.
I think it maybe be fuel or ignition related.
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