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Discussion Starter #1
My 95 T-Bird with 153k miles, and my GF's 96 XR-7 with 88k - can't get rid of the WOT pinging from 3000 RPM on up! The 95 needs 89 octane, and the 96 needs 93 octane just to keep from pinging on part-throttle, but no octane increase gets rid of the WOT pinging!

Both cars have a full tune-up & fuel filter - mine includes cleaning the EGR ports (made it worse!), and combustion chamber cleaner run thru it.

Changing from the K&N back to a paper filter helps a lot, so they have to be too lean. Next I will try colder plugs - currently running standard Autolites. The last set was very clean but whitish - the porcelain was chalky, but not melted or anything!

Any tips would be greatly appreciated!

Thanks!
Al
 

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Discussion Starter #3
Pretty sure no vacuum leaks, car runs great otherwise! How can I check the fuel pressure? Looks a little cumbersome on this car!

Where can I get AWSF-22C spark plugs? No luck so far!

Thanks!
Al
 

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Discussion Starter #5
YT90SC said:
Clean your MAF.
Already cleaned the MAF. Didnt notice any difference.

Al
 

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Discussion Starter #7 (Edited)
Actually, I pulled the octane plug last night. The car felt a little slower, and it did reduce the detonation, but still didnt completely eliminate it! It pinged from 4000 on up, though it was more faint.

Since that didnt fix it, I doubt colder plugs will help much - unless combined with something else to richen it up, like a resistor in the air temp sensor or higher fuel pressure.

To re-cap: my car has 153k, my GF's car has 88k - both have WOT ping regardless of the octane. Mine is worse from the extra carbon build-up, I guess. No pinging climbing hills or part-throttle though.

Not ever going WOT is not fun, and builds up carbon - making it a catch-22!

Thanks,
Al
 

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i say there's extra air coming in somewhere from a leak thats not being metered by the MAF, or your MAF is failing and not giving the computer the proper voltage signal, or insufficient fuel pressure at high RPMs.....sometimes even the EECs go bad...or a combination

might just have to fork over those $60-$70 and have a dealership diagnose it so you can have a concrete answer in writing
 

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Discussion Starter #9
I checked everywhere for air leaks. Both cars are running EXCEPTIONALLY well, except for the WOT ping. Mine has pinged at WOT ever since I had the car - 4 yrs and 40k miles!

An ex-GF had a 96 Mustang V6 with 50k miles, pinged! That's 3 for 3 for OBD-II Fords that I have been around a lot that ping! I had an 88 T-Bird - great car! Pinged! It did have 206k miles when I sold it and it is still going!

I have come to the conclusion that these cars are set up borderline too lean from the factory for emissions. As soon as it gets some carbon build-up, it pings.

I will take off the MAF again and literally give the hot-wire a shower of contact cleaner! It just seems crazy that a stock vehicle needs more fuel than the factory provided. But if I want to get on the car I guess I will have to richen it up!

Thanks,
Al
 

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T6Rocket said:
It just seems crazy that a stock vehicle needs more fuel than the factory provided.
actually, that is crazy...i don't know where you're getting that idea from.....most cars are factory-set up to go rich upon WOT ......when my car was stock, A/F would go below 10:1 starting at 3.6k RPMs....now, i'm not sayin ALL cars do this, but it is true in general....that i why i say that something is definitely wrong somewhere.....so before you start richening things up by putting in bigger injectors or something crazy like that, it would be wise to have it looked at so you can have something to work with instead of blindly replacing things........sorry that i can't be of any more help :zdunno:
 

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Discussion Starter #11
I know that cars usually come setup very rich from the factory - esp turbo cars. I would pay a person (tuner) to check out my car, but NO WAY am I taking the car to the dealer for this!

The car's driveability is at 100% otherwise, it's just the WOT knock that has plagued every Ford I have ever been around that's starting to drive me crazy!

Is there a place to plug in a voltmeter to monitor O2 sensor voltage on these cars? Then I could at least see if the voltage is dropping at WOT. I used to tune my Turbo DSM that way back in the day before widebands were commonplace.

Thanks,
Al
 

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i can tell you right now since youve already spent your money, take it to your ford dealer have them run the baro pressure on the maf my money is both mafs are bad, my car did the same thing when its maf was bad, i cleaned it, it kept throwing lean codes and geting crappy mpg

id take it to a ford dealer have them run a diagnostic test on your sensors, if they dont come up with anything, then its time to look over your fuel and air deliver system bud, but im beting on the maf
 

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when is the last time you change your FUEL FILTER??? if never then it might explain it.:D
 

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If I'm mnt mistakd and I sumtim am. Digimoto can tel you the voltage of certain seoncrs if you have OBDII. Just my 2 cents. Thank you Jake and Will for wshing my happy 21st!
 

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Discussion Starter #16 (Edited)
I have changed the fuel filter - twice in 4 yrs! I have not spent any money so far on trying to remedy this, other than Sea Foam.

Can a bad MAF cause hard-starting? I had a crazy hard-starting problem recently. I would turn it over and over and it wouldnt start, then I would let off to try again, but before I could try, the car would usually sputter to life and start running! It did this for 2 weeks, now it is fine! I did add Amsoil PI fuel injector cleaner, but it went away the day before I put it in!

If the MAF is bad, wouldnt I have a check engine light? I will try cleaning it again. I will pick up the tamper-proof T-20 Torx bit and take it "all the way" apart this time.

Thanks!
Al
 

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Casper said:
when is the last time you change your FUEL FILTER??? if never then it might explain it.:D
i dont think it would cause as sever pinging as he is describbing, maybe a little bit really high up in the revs
 

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mylittleblackbird said:
If I'm mnt mistakd and I sumtim am. Digimoto can tel you the voltage of certain seoncrs if you have OBDII. Just my 2 cents. Thank you Jake and Will for wshing my happy 21st!
the sensor can still be in voltage spec but be out of wack like crazy, at ford the run a baro presure test on the sensor, so that cant always find out if the sensor is messedup, mine was in the correct voltage spec, but the sensor was bad when i check it, found out from the ford dealer
 

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Does anyone know of some private people that can run the baro test INSTEAD of a Ford dealer? I would have to make an appt and then leave the car then get a ride home, then another ride to the dealer, pay a high price etc. no thanks.
I live in south east Michigan. Is there a reliable person that can do the baro test while I wait?
Danford1
 
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