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#1 OFFLINE   ratrace427

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Posted 01 July 2017 - 04:36 AM

I have a check engine light that i keep clearing out every few weeks. I have closed the gap on the plugs to .022 i think. They really should not need to go any smaller. I didnt write down the plug part number down to look them up but they must not be copper core. I have a good knowledge of plug designs but when it comes to temp range it is a trial and error thing.

 

What temp range do i need for a 650 hp super snake?

 

thanks

john



#2 OFFLINE   ratrace427

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Posted 01 July 2017 - 04:44 AM

i see now that NGK-TR6 is the choice. I am pretty sure that is what i have, the "V" power BS. I will have to pull a plug to confirm but im 90% sure that is what i am running and i still get misfire. It comes in copper or platinum? Maybe i have the platinum...


Edited by ratrace427, 01 July 2017 - 04:46 AM.


#3 OFFLINE   shelby001

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Posted 02 July 2017 - 05:39 AM

Is it a code or just check engine light & why do you think its the plugs, or a plug?



#4 OFFLINE   mhr1961

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Posted 02 July 2017 - 07:40 AM

Check coil on plugs and O2 sensor.

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#5 OFFLINE   ratrace427

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Posted 02 July 2017 - 12:14 PM

isnt a code and a engine light the same thing? The code turns the light on and a bad O2 would have its own code. faulty O2 would also make for a rich or lean engine and my wide band says all that is good. The engine code says multiple misfires. I have thought about the coil packs but that would mean the factory coil packs are not powerful enough for 15psi and I dont think that is true. I was thinking the simple answer was the right one. Plugs are blowing out. Whatever it is, it is happening on multiple cylinders.

 

Maybe the tune is doing something so fast that i cant see the wide band respond. 


Edited by ratrace427, 02 July 2017 - 12:19 PM.


#6 OFFLINE   mhr1961

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Posted 02 July 2017 - 08:54 PM



P0300 Ford

Posted on November 10, 2013 by fordobdcodes

Ford P0300 OBD-II Trouble Code Definition:

P0300 Random Cylinder Misfire Condition

P0300 Ford OBD-II Trouble CodeDescription:

OBD Trouble Code P0300

Random/Multiple Cylinder Misfire Detected

What does the code mean? OBD-ii Code P0300 definition:
Basically this means that the the cars computer has detected that not all of the engines cylinders are firing properly. A P0300 diagnostic code indicates a random or multiple misfire. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. A P0302 code, for example, would tell you cylinder number two is misfiring. Unfortunately, a P0300 doesnt tell you specifically which cylinder(s) is/are mis-firing, nor why.

Symptoms Sumptoms of OBD code P0300
the engine may be harder to start the engine may stumble / stumble, and/or hesitate other symptoms may also be present

Causes Causes of the OBD-II code P0300
A code P0300 may mean that one or more of the following has happened: Faulty spark plugs or wires Faulty coil (pack) Faulty oxygen sensor(s) Faulty fuel injector(s) Burned exhaust valve Faulty catalytic converter(s) Stuck/blocked EGR valve / passages Faulty camshaft position sensor Defective computer

Solutions If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back. If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. Ive also heard in other cases the problems were faulty fuel injectors. Random misfires that jump around from one cylinder to another (read: P030x codes) also will set a P0300 code. The underlying cause is often a lean fuel condition, which may be due to a vacuum leak in the intake manifold or unmetered air getting past the airflow sensor, or an EGR valve that is stuck open.

Edited by mhr1961, 02 July 2017 - 08:55 PM.

2008 Shelby GT Convertible CSM#08SGT1754
Vista Blue/Silver Stripes,Automatic Transmission,Interior Upgrade Pkg-Satin Alum Panels, HID Headlamps, GT Upfittters Pkg, DVD Navigation System, Heated Seats, Active AntiTheft, Ambient Lighting, Shaker 500 Audio, Sirius Satellite Radio

No Major Mods-Only Mods are Dress Up Items that can be removed easily to be able restore car back to original condition in an afternoon
Dress Up Items to Individualize my 08SGT:
SAI-"Shelby GT" Billet Aluminum License Plate Frame
SAI- Berg "S" Cobra Black/Silver Wheel Center Caps
SAI- Berg "S" Cobra Brushed Finish Stainless Steel Dead Pedal
SAI- Berg "S" Cobra Custom Made 12 V Power Plug

SAI- Berg "S" Cobra Trunk Lock Center Emblem

SAI- "Shelby GT" Logo Front Floor Mats
SAI- Shelby GT Billet Aluminum Grille-Lower

Scott Drake 6 Way Programmable Sequential Tail Lights
Ford- OEM Ford Racing Oil Filter (Mobil 1)
Ford- OEM "Personalized " 19.125" Shortened Antennae to match roofline with convertible top in the up position
Ford- OEM Driver's Side SunVisor signed and dated by CARROLL SHELBY 10/23/10
3M ClearGuard "Bra" on First 2" of Hood and Front Fenders


#7 OFFLINE   ratrace427

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Posted 03 July 2017 - 02:58 PM

very nice info. Thanks! I did get a cylinder two misfire once before but the plug was gaped larger than the other 7. I also felt the misfire stumble with the cylinder two code. This time with the multiple misfire i did not feel anything at all. If i remember correctly i was just cruising and the light came on.

 

This info you provided states that a lean condition will cause the misfire.

 

I wonder if a "misfire"  is also considered detonation/pre ignition?  In my turbo dodge mind a misfire is spark blow out but maybe this is detonation because of the tune pushing the limits. 

 

"Lean misfire refers to an engine misfiring because the air-fuel ratio is not properly balanced. Ignition misfires occur when either the spark plug, wire, distributor, or ignition coil fail, causing an engine misfire on the specific cylinder." I looked it up  :clapping: 

 

Thanks again for this info. I am now on the path of a "LEAN misfire" (detonation) not a "Ignition misfire" (blowout)

 

Only way to fix this is with a new tune =(. I have not learned where to go for Ford tuning yet. I wonder if Las Vegas could send me one after i buy a programmer.  I did find out that John Lund from somewhere did a "remote" tune for the P.O. at the local mustang speed shop.



#8 OFFLINE   twobjshelbys

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Posted 03 July 2017 - 04:04 PM

A new tune may be needed but you didn't say what you have. Does your car have a non-factory tune in it? In any case, why did you regap plugs? If factory tune they should be set according to the factory recommendations.   On the other hand, if you have a custom tune, then you should set the plugs (both type and gap) according to that recommendation.  The reason I mention this is because you think you need to buy a programmer.  If there was a custom tune you should already have one.   I just think we're not getting the full story.


Cheers,
Tony

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#9 OFFLINE   ratrace427

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Posted 03 July 2017 - 06:54 PM

yes, it has a custom tune. I re gaped the plugs because i was having #2 misfire and #2 had a larger gap than the rest. This car has passed threw three different owners and none of them know anything about cars. They all spent big money having other people do the work. It is difficult not having any more info. I might have to start over with the tune unless this John Lund guy can help me out. I will see about tracking him down. I think he might be in Chicago area where the car started its life. If i buy a programmer then it might be as simple as putting the super snake tune on from las vegas. The only thing original is the long block so most likely i need to find someone to do tuning.

 

Maybe just learn how to do it myself. i wonder how much $ it would be for the software. 



#10 OFFLINE   twobjshelbys

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Posted 03 July 2017 - 07:25 PM

The software is only part of it.  You need a dyno too...

 

I would suggest starting over with a good tuner. 

 

Transplanting a tune from another custom tuned vehicle will also require all of the other things they did to the car.  For example, if the new configuration included a different throttle body you will need that.   Same for a CAI.

 

I don't know how these "tunes" live, but it is possible, even likely, that they are somehow "signed".  Vanity lives on forever, so chances are there is some kind of identifier present that might help trace it back to the original.   Going to a new tuner will essentially start everything over, and he'll probably require some inventory of what's there and changes to accommodate the new tuner's style.

 

Whatever you do don't take it to a Ford dealer or they will likely restore it to factory.  I can tell you from experience that the factory tune bricks my Ford GT unless I also restore some original hardware.

 

Good luck

 

 

PS.  I strongly discourage the Do It Yourself strategy here. I attacked a highly programmable DFI (Digital Fuel Injection) system in my Cobra, and after buying the software, and diagnosing the root cause (altitude compensation table was not populated) took it to a tuner that knew how all the knobs interacted.  Unless you're going to make a career out of it, it's not worth the investment in time.  And there are no classes or books and the cost of a failed experiment is a rod through the block.   This is a "Don't Try This At Home" task.


Edited by twobjshelbys, 03 July 2017 - 07:27 PM.

Cheers,
Tony

Motto: You can have fun going fast. ... but ... You don't have to go fast to have fun.

Current:
2006 Ford GT Heritage Edition, 650 RWHP, 600 FtLb torque.

Former:
CSX4005LA - Shelby Continuation Series Cobra. The most fun you can legally have, sitting in a chair, in public.
CSM08SGT2228 - Barrett Jackson Special Edition Convertible, 5-speed, Kenne Bell S/C. Carroll Shelby Children's Foundation Gift at Barrett-Jackson 2009 Scottsdale
CSM08SGT2247 - Barrett Jackson Special Edition Convertible, Automatic. Kenne Bell S/C installed. WHOOT!
Simple Mods: Electrochromic mirror with compass/temp/HomeLink, Ford HD Radio with iPod, lower billet grill insert, sequential tail lights.

#11 OFFLINE   ratrace427

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Posted 04 July 2017 - 04:22 AM

hmm agreed. one key stroke could hurt the engine. sometimes paying for the professional is better than learning and paying the price and time. Just like differentials and transmissions. I always pay to have these things done so it is quick and i dont have to buy the special tools.  



#12 OFFLINE   NJPat

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Posted 05 July 2017 - 04:40 AM

Jon Lund is easy to locate - if you want a Ford tuning specialist

 

Simply look on the web for Lund Racing, and make a call (or send an email)






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