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Injector woes

 
Old 02-12-2013, 03:26 PM
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vanster
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Default Injector woes

Recently I'm getting a misfire, popping etc.
Two ways to get rid of it, 1) The 'ol Italian tune up. (drive the snot out of it for 10 miles or so)
2) Pint of injector cleaner at $10 per pint from my local Chevron dealer.
After a tank or two it comes back. Does this mean I need to take my injectors apart and clean them?

I don't let the tank get below 1/4.
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Old 02-12-2013, 05:43 PM
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dr bob
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Can't say for sure that the injectors are the problem. If they are, cleaning is a good idea especially if they haven't been thoroughly cleaned in the last 50k or so, maybe less if your car is a not-too-regular driver. Mine has been my DD for years, gets "top tier" gas, but still benefited significantly from clean injectors.


Meanwhile, back at the ranch...

Misfire can be caused by almost anything weakening in the ignition system too. Tired plugs, old leaky or cracked/broken wires, worn cap and rotor. A weak spark combined with a weak mixture is a recipe for misfire. If you are going to have the tools out anyway to remove the injectors for cleaning, take the time to inspect the ignition system bits. Replace any stuff that's at all marginal.
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Old 02-13-2013, 09:14 AM
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While the spark plugs are out do a compression check (popping) could be valve related. i.e. Carbon build up.
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Old 02-13-2013, 10:49 AM
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Imo000
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Originally Posted by dr bob View Post
Can't say for sure that the injectors are the problem. If they are, cleaning is a good idea especially if they haven't been thoroughly cleaned in the last 50k or so, maybe less if your car is a not-too-regular driver. Mine has been my DD for years, gets "top tier" gas, but still benefited significantly from clean injectors.


Meanwhile, back at the ranch...

Misfire can be caused by almost anything weakening in the ignition system too. Tired plugs, old leaky or cracked/broken wires, worn cap and rotor. A weak spark combined with a weak mixture is a recipe for misfire. If you are going to have the tools out anyway to remove the injectors for cleaning, take the time to inspect the ignition system bits. Replace any stuff that's at all marginal.
Using or not using "Top Tier" gasoline has nothing to do with injectors getting clogged. Regular gasoline is not dirtier than premium. People have to stop spreading myths like this.
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Old 02-13-2013, 11:24 AM
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Originally Posted by Imo000 View Post
Using or not using "Top Tier" gasoline has nothing to do with injectors getting clogged. Regular gasoline is not dirtier than premium. People have to stop spreading myths like this.
Not so certain that major sellers of petroleum products would agree with that. cheaper grades of gas tend to leave deposits (varnish sorts of buildup on valves, injectors and the like) where some better grades of gas do not. Shell Techron comes immediately to mind as a gas that tends not to leave as many deposits, and that can be demonstrated, and if you have friends at Shell they can supply lab results, blind tests, and competitive data to this point. By the way, I suspect other "good" gas has similar additives, cheaper gas, not so much. One other point, I am not speaking to regular versus premium, but rather good grades of gas versus cheap gas.

Last edited by tmpusfugit; 02-13-2013 at 11:31 AM. Reason: need to learn to spell
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Old 02-13-2013, 04:49 PM
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Good thoughts
I drive my car at least 2 to 3 times a week and I only use Chevron Premium gas
I have replaced the wires, cap, plugs, fuel filters less than 5k ago.
As I mentioned if I put a pint of Techron in the tank it goes away until the next tank or if it sits a for 2 or 3 days. Saturday I did about 50 miles of freeway driving and it went away, for a while.
I have not cleaned the injectors and I have no idea if they have ever been cleaned. I have 106k on the clock.
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Old 02-13-2013, 05:30 PM
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Sounds like time to get the injectors cleaned...we don't really have much other choice as OEM's/Porsche seem either very costly or NLA depending upon whom you ask. And there does not appear to be any decent replacements for the 16V injectors. I would love to be proven wrong on the NLA comment by the way, as I have a couple of sets that should be cleaned I think, or replaced....
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Old 02-13-2013, 06:01 PM
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Originally Posted by tmpusfugit View Post
Not so certain that major sellers of petroleum products would agree with that. cheaper grades of gas tend to leave deposits (varnish sorts of buildup on valves, injectors and the like) where some better grades of gas do not. Shell Techron comes immediately to mind as a gas that tends not to leave as many deposits, and that can be demonstrated, and if you have friends at Shell they can supply lab results, blind tests, and competitive data to this point. By the way, I suspect other "good" gas has similar additives, cheaper gas, not so much. One other point, I am not speaking to regular versus premium, but rather good grades of gas versus cheap gas.
Considering all gasoline in an area comes from the same places for the most part...there is no such thing as cleaner or dirtier gas.

Most addatives happen at the tanker fill, not in the refinery
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Old 02-13-2013, 06:21 PM
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Originally Posted by tmpusfugit View Post
Sounds like time to get the injectors cleaned...we don't really have much other choice as OEM's/Porsche seem either very costly or NLA depending upon whom you ask. And there does not appear to be any decent replacements for the 16V injectors. I would love to be proven wrong on the NLA comment by the way, as I have a couple of sets that should be cleaned I think, or replaced....
http://www.fiveomotorsport.com/product-search/?v=28369
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