Going after the BUMP isuue..

[lord Kelvin]

Wow, that's interesting. I have a set of APP765 plugs in the garage waiting to be installed. I've always used Motorcraft plugs, but thought I would try the Autolite plugs since I use those in all my other cars successfully.

I saw this on the autolite website: http://www.autolite.com/pdf/Half_FullThread.pdf
This suggests the thread difference is by design.

I totally believe changing plugs fixed your problem, but I'm not ready to conclude these plugs don't work based on one data-point. I say this because given just one data-point, you can extrapolate in any direction.

So the question is: is anyone using APP765's successfully?

[garync1]

Wow.. You Bring up a good point with the web site explanation.. Funny thing about all this.. Every time I buy a part I always compare it to the one I am replacing.. So my thinking is I saw the same the first time or I did not check. I may have made sure they were the same size but did not check the thread count. Or I did. Who knows.. The thing is I replaced the fronts and got no change so I assumed my back plugs were ok.. I just decided to change the rear plugs to go ahead and rule those out. I pulled my coil and checked it and it was fine.. So I put the plugs in and drove it yesterday and nothing happen. So today i went ahead and did the long drive test and nothing happened. So I figured it had to be the plugs.. They were replaced a year or 2 ago. Makes me wonder to if anyone else is running the APP 765 with success or are most running the APP 105.. Then again did Auto light put that out to cover there behinds.. LOL Sure seemed like it went in a couple of turns deeper to me.LOL I wish I kept my motorcraft plugs.

[Andrew1941]

Congrats on locating the issue.

I did so many things all at once too and it was difficult to determine why the bump went away, DPFE, plugs, wires, who knows? I did install Motorcraft plugs, but I had a cracked one that came out so she was running rough before. In my case the bump was the DPFE sensor.

[Ed_Strong]

WOW... Sweet deal, I'm really happy for you Gary. Glad you got it working better now and I hope the new plugs was all the money you had to spend to get it fixed!

I would need to check my plugs to see which ones I'm running, I don't have any engine idle or drivability issues.

[garync1]

You know after all this it would be nice to know if someone had the same issue with the APP 765.. The site that Kelvin put up above makes me wonder why Autolight had to explain it to begin with.. The APP 105 yes is the same plug in its right.. But I think it sets deeper in head from what they claim.. It seem it would have to.. Just wish I kept my stock Motorcraft plugs. That would solve my theory.. I just will say this. I have put wrong plugs in and had the piston top out on them before in a car once. Can't remember what make it was but I got lucky it just flatten the electrodes and not break off or damage the piston. So I know you can put too long of a plug in.. Just glad the thing did not start up.

All in all Today on the way home I saw my gas millage go up. Its now a steady 17 mpgs in the city. Also drove 33 miles to next Town last night and saw 22mpg's in the rain.. That same trip had drop to 18 -19 mpg's.. Also my Trip to Florida on the new trans only got 20mpgs average.. Not sure if it was the New trans or my dang plugs.. Or both.. But I have notice it does not bog down like it did right before the bump , No.. I did not replace the coil or plug wires. Just the plugs.. Although I may have held off on the new trans if I had changed my plugs first. LOL.. But then again I would have rented a van to go to Florida.LOL. Now I just know my vans reliable.. However I did notice the darn front main seal is starting to leak a little. Not bad though.. It has over 100,00 miles.. So that's to be expected..