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Old 12-15-2015, 01:34 PM   #1
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Default rough idle only when cold???

My 1.8 turbo car with LINK ECU started running real rough at idle but cleans up at operating temp or when cold above about 3k rpm.
I pulled plug wires 1 at a time and it seemed to not change when the skip when I removed wire #3.

This is getting progressively worse. Last night, it would not start once it got to operating temp. I waited until this morning and it started right up....still with the skip but it started.

I was thinking spark plug or injector. Any thoughts?
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Old 12-15-2015, 03:52 PM   #2
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Quote:
Originally Posted by vincentrx7 View Post
My 1.8 turbo car with LINK ECU started running real rough at idle but cleans up at operating temp or when cold above about 3k rpm.
I pulled plug wires 1 at a time and it seemed to not change when the skip when I removed wire #3.

This is getting progressively worse. Last night, it would not start once it got to operating temp. I waited until this morning and it started right up....still with the skip but it started.

I was thinking spark plug or injector. Any thoughts?
What head / lash adjusters do you have? When was the last time you adjusted your valve lash?

I ask this because this was one of the symptoms that presented when I had a failing intake valve. Car ran very rough when cold until it warmed up. When the valves had worn enough that when they were warm they were still leaking.... thats when I knew I had a real issue.

Could be any number of things....and this is probably the least likley.....but younare looking for ideas.....so there is an idea
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Old 12-16-2015, 02:44 PM   #3
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Thanks TNTUBA. I hope this is not the issue.
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Old 12-24-2015, 03:45 PM   #4
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Any other thoughts? I replaced the spark plugs and it is better but not right. The missing seems to go away above 1800-2000 rpm.
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Old 12-28-2015, 05:24 AM   #5
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Well, the next step could be to swap injectors, although it does not probably explain why it runs well on higher RPM. Is the air/fuel ratio OK on idle and at 3k RPM if you turn off the EGO corrections?
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