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914World.com _ 914World Garage _ Any spark-plug readers in the house?
Posted by: SirAndy Apr 10 2010, 08:47 PM
Do these look OK?
I haven't been reading spark-plugs since my dirt bike racing days.
On my bike, those would have indicated a slight lean condition. 
What about a 993 3.6L motor? Still too lean? Or OK?
Andy
Attached image(s)
Posted by: TC 914-8 Apr 10 2010, 09:05 PM
Although I am far from an expert on FI engines They look lean to me
Here's a Link
http://www.verrill.com/moto/sellingguide/sparkplugs/plugcolorchart.htm
One other concern There is only 10 ?
Posted by: Jeffs9146 Apr 10 2010, 09:22 PM
If it was my motor I would not be upset!! Maybe a bit on the lean side but not too bad! How many miles??
Posted by: SirAndy Apr 10 2010, 09:23 PM
One other concern There is only 10 ?
Yo. I know that ...
Two of the lower ones on the passenger side can only be removed with the engine dropped down about 2 or 3 inches. I'm going to do that next weekend, i ran out of time today.
Andy
Posted by: SirAndy Apr 10 2010, 09:26 PM
If it was my motor I would not be upset!! Maybe a bit on the lean side but not too bad! How many miles??
On the old plugs? No idea.
I actually never had them out. They were in there when i bought the motor, i just fired it up and it ran.
Andy
Posted by: Jeffs9146 Apr 10 2010, 09:29 PM
Notice the darker tips, I think that is a good thing! Have you run it on a sniffer?
PS: Those are not cheep plugs!!
Posted by: McMark Apr 10 2010, 09:29 PM
Check you distributor caps next time as well. 
Posted by: TC 914-8 Apr 10 2010, 09:32 PM
Here's an Idea, that won't cost too much. Being in Kalifornia, Stop by a smog test place (pass or don't pay) have them throw a sniffer up the tail and give you a reading.
All in all a bit on the lean side but burning clean. Especially not knowing the age. A new set of Bosch-4'2 or E2's and check them in a month.
Posted by: rdauenhauer Apr 11 2010, 12:39 AM
Ha! I used to race a H1 and had to be an EXPERT at plug chop reading.
If it were me Id look for a little more tan than white, nut as others have said a little on the lean side but thats where the power is at!
Posted by: messix Apr 11 2010, 01:40 AM
need closer shots of the insulator and the the tip of the electrode to tell you anything that would be of any worth. and pulling plugs out of a street car and trying to read rich or lean when it has idled is worth less for any judgement on full throttle mixture.
closer shots will show if there is any deposits on the insulator from detonation, and if the electrode is erroding from over heating from lean conditions.
Posted by: Racer Chris Apr 11 2010, 05:24 AM
Unleaded fuel doesn't provide the same distinct color comparisons on spark plugs as the old leaded fuel did. As Messix noted, aluminum deposits and erosion are important telltales though.
We had some of the plugs out of the 3.6 in our shop last week and they looked much as yours appear.
Have you put a scanner on the OBD2 to check for fault codes?
Do you have the stock ECU chip or an enhanced performance chip? The performance chip in the car we have here tries to keep the AFR around 13.0 +/- 0.2, but the engine was lean and pinging at moderate load/low rpm until we replaced the O2 sensor.
Posted by: ME733 Apr 11 2010, 08:42 AM
...............ANYTHING that WHITE is too LEAN.....look closely and you will find hard /melted/fused ..deposits....the plug tip is so hot it,s melting....Richen up the mixture before you burn a valve, hole a piston, or worse.........(needs a little more brown color to get "normal looking".)......and as mentioned check the oxygen sensor, a old or defective one will alter fuel mixture..+.check fuel filter..+..did you add race gas or an additive , drive awhile , before pulling plugs?........Ideas to consider. the chart in an earler post is Identical to the CHAMPION spark plug chart and is an excellant referance for spark plug condition..........
Posted by: Racer Chris Apr 11 2010, 09:02 AM
...............ANYTHING that WHITE is too LEAN.....
I think the flash on his camera causes a misleading brightness to the picture.
Posted by: charliew Apr 11 2010, 11:12 AM
I agree also the resulting condition is from probably a idle period that doesn't show the rich or lean condition at wot or under a good load condition where det usually occurs and could cover up the small specks from det unless you use a loupe or magnyfing glass under a good light. The additives in unleaded gas in the different parts of the country make plug reading a problem unless it is done on new plugs at wot or under a load and immediately shut off. The air cooled motor is way more critical than a water pumper because the head temps vary so much. The sniffer at various rpms would be the easiest way to get real information or a afr gauge in the car all the time. The four seasons in the country will mean the fuel properties change more than we can keep up with on pump gas.
I think reading plugs is for racers that change plugs regularly and only run race gas.
Posted by: McMark Apr 11 2010, 11:23 AM
Yup, they're not that white.
Posted by: kg6dxn Apr 11 2010, 02:50 PM
Theres a guy in Concord with a dyno and lambda sensor. I took my last car there to tune the EFI. I think it cost me $200 for the day.
Posted by: underthetire Apr 11 2010, 03:11 PM
Those look totally normal with Kalifornias alcohol content in the fuel.
Posted by: Vacca Rabite Apr 11 2010, 05:57 PM
Andy, do you have an Air Fuel Meter sniffing your exhaust? That will tell you much easier if you are rich or lean.
I am thinking about adding one to my little 4.
Zach
Posted by: sixnotfour Apr 11 2010, 06:53 PM
modern engine is smarter than you think.
Posted by: McMark Apr 12 2010, 12:16 AM
Zach, it tells you if you're rich or lean, but it doesn't tell you if you too rich or too lean. 14:1 is almost never the right value. Especially with a modern motor. I'm sure you already know that, but for others who might be reading, I thought it was worth saying.
Posted by: '73-914kid Apr 12 2010, 12:29 AM
Okay, an old fashioned dragster taught me a few of these.. not sure on the accuracy though.. the line on the ground strap looks to be in the right place meaning the timing is optimal for that combustion chamber. The plugs look slightly lean, but the flash could be doing that.. they look really nice though Andy. The darking electrode would also imply that it's rich on idle mixture.
That's a nice clean burn though.. Even if it wasn't the flash that makes them seem so white, you should look at how white/grey racing spark plugs are.. no comaprison..
Posted by: ME733 Apr 12 2010, 08:12 AM
............OK everybody.......You think the flash from the camera is making the SPARK PLUGS look to "white"....this is possable... SO lets ask andy to rephotograph the spark plugs in a more normal lighting condition.....One other thought, the multiple ground spark plugs, will restrict FLAME propogation in the combustion chamber. I,m thinking these are not factory recommended spark plugs......and generally you (it,s possable to tell)....can tell if the heat range and spark plug temperature is correct by reading the spark plug threads....Andys plugs show no color change from top to bottom....possably due to the photograph and lighting.................just a few thoughts..........................murray.
Posted by: sean_v8_914 Apr 12 2010, 09:47 AM
looks like a 993/964 plug to me. do an AFR. I,m sure you can get your hands n an LM1.
looks like a stock chip'd DME to me
Posted by: SirAndy Apr 12 2010, 10:48 AM
I,m thinking these are not factory recommended spark plugs......
Stock 993 spark plugs (Beru). That's the way they come from the Factory.
I replaced them all with a set of the same.
I think i'll look around for someone with a sniffer and maybe even some software to plug into the OBD1 port ...
Andy
Posted by: mightyohm Apr 12 2010, 11:59 AM
They look ok to me, very similar to the plugs I have removed from most modern cars that aren't running pig rich... Slight grey color on the insulator, right?
Posted by: RobW Apr 12 2010, 04:30 PM
Check you distributor caps next time as well.
YES...
You do NOT want to bust the timing belt in the distributor either....
Posted by: McMark Apr 12 2010, 05:57 PM
Distributor timing belt is new. 
Modern FI runs the motors lean when it can to help emissions. So yes, it's running lean. But only when it's supposed to run lean. Ergo, it's running fine.
Posted by: 70_914 Apr 12 2010, 06:15 PM
PS: Those are not cheep plugs!!
$2.67 each. Seems cheap to me.....
Posted by: McMark Apr 12 2010, 06:29 PM
Where are they $2.67 each?
Posted by: KELTY360 Apr 12 2010, 06:48 PM
SO lets ask andy to rephotograph the spark plugs
Do you understand what you're asking? That's a shaky proposition at best.
Posted by: 70_914 Apr 13 2010, 10:32 AM
Where are they $2.67 each?
WorldPac with my wholesale discount. I don't know what year the engine was out of, but I chose a 1992 just to get an idea of price.
Posted by: charliew Apr 13 2010, 10:37 AM
I ran across this in another forum I was on.
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp
Posted by: McMark Apr 13 2010, 12:08 PM
Where are they $2.67 each?
WorldPac with my wholesale discount. I don't know what year the engine was out of, but I chose a 1992 just to get an idea of price.
Nice to know, but not really pertinent for the home buyer is it?
$7.75 each at Pelican
Posted by: 70_914 Apr 13 2010, 02:24 PM
Where are they $2.67 each?
WorldPac with my wholesale discount. I don't know what year the engine was out of, but I chose a 1992 just to get an idea of price.
Nice to know, but not really pertinent for the home buyer is it?
$7.75 each at Pelican
I don't know. You would have to call your local Car Quest (they own WorldPac) and see what they sell for retail.
I don't remember anybody posting an "I'm-looking-for-parts-for-my-project-can-anybody-hook-me-up-with-wholesale-pricing" topic. Now THAT would make it pertinent for the home buyer....
Posted by: charliew Apr 16 2010, 10:19 AM
My youngest son thinks I'm being rude everytime I try to get something for less than retail. He is my son and I can't understand why he didn't learn this process from me like all the other stuff I taught him. After all he does drive a suby not a porscha.
Posted by: Phoenix 914-6GT Apr 16 2010, 10:44 AM
Where are they $2.67 each?
WorldPac with my wholesale discount. I don't know what year the engine was out of, but I chose a 1992 just to get an idea of price.
Nice to know, but not really pertinent for the home buyer is it?
$7.75 each at Pelican
I have a bag full of these as well from WorldPac (about $2) but even still $7.75 isn't bad when you compare them to the 100k mile platnum plugs some Hondas and Toyotas are suppose to have. I believe they are $15 a plug at cost.
Posted by: McMark Apr 16 2010, 10:53 AM
Remember Andy needs 12 of them. 
Posted by: Phoenix 914-6GT Apr 16 2010, 10:58 AM
Yeah, that can add up 
Posted by: ghuff Apr 16 2010, 12:56 PM
That is too lean and possibly too hot of a plug for your app...
Better pictures are needed. Can you get some macro shots of the insulators and center electrode?
If those came from a turbocharged or supercharged motor, I would be very concerned, or something with a lot of compression and timing.......
You can get away with lean in certain instances, I'm also assuming your 993 motronic has multiple piezo's picking up any knock.
Does your motronic have misfire detection at all as well?
Is the car missing at all?
I do not know what air cooled motors like mixture wise, but too lean = higher egt's, more heat, etc....
This all may be worthless, I do not do air cooled stuff, and do not know what they tolerate. But anything I own, that would be cause for concern.
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