Random RPM drop

[STANN]

Put the KKM intake on a coupla weeks ago (runs great) but at WOT in second gear around 3200-3500 RPM, there's about a 500 RPM drop (really noticeable in engine tone and on tach.) Anybody know why this is happening? I dont remember it happening before the intake but maybe it did and i just never payed attention...Its really starting to bother me....maybe need to clean the MAS??

 

[Alec]

just a thought, did you reset the computer when you installed the intake? don't think that's it, but it could be. Or, it could just be your torque converter locking up.

 

[DarkFox1]

it sounds like your torque converter to me, I didn't have exactly this problem , but I have hda that happen to me before, upon asking the "ford certified transmission specialist" at my local dealer, he explained that it was a "lockup" and that its perfectly normal and nothing to worry about.

If you didn't reset your computer that may be why its doing it. Or, if you started off after a fresh reset driving it hard, it may have adapted in a strange way.

I would try resetting the computer again, this time idle it for 10-15 minutes and then baby it for a short drive and turn it off, then whenever you go somewhere drive it easy for probablly 2 oe 3 days, then it should be ready to play.

if that doesn't fix it, and you have the time/money for a shop to look it over, you may want to take it down somewhere and drive em around, see what they think.

IMO ford wont be able to help, chances are thye'd blame it on the filter 100%, they've given me a hard time about mine a few times, but never taken any action. (probablly cos they're legally prohibitted to take any )

 

[aldive]

Originally posted by DarkFox1
they've given me a hard time about mine a few times, but never taken any action. (probablly cos they're legally prohibitted to take any )

Why would you (1) put up with anyone giving you a hard time (2) take anything to Ford??

 

[DarkFox1]

warranty, and they dont give me a hard time.. they're jst like.. if I say its doin something they're like "its probablly that filter, you know you're not supposed to put filters that big on there, its probablly getting too much air" and then thats the end of it.. its just like.. a poke with some pencil lead.. it doesn't hurt and theres no action to be taken, its just annoying at best. cos they're legally prohibitted from rejecting me for warranty for for this thing

we bought extended warranties. .its 5 years old and still under some form of warranty. Its major things tho.. like if my engine block just.. blows up or something its covered, otherwise its probablly not.

 

[Alec]

When I took mine in for an oil change to a dealer in CA they said, "You know, you're not supposed to put a large supercharger or nitrous on your 4.0."

Then they proceeded to take it out for a test drive

 

[DarkFox1]

I dont blame em, I'd love to take your truck for a testdrive lol, its a great ride.

I've been chewing on a recommendation by some of the people here to go to a non-familiar dealership, and try to test drive a '97 5.0 XLT 4dr 2wd with a 373 LSD a 4R70W and about 67k miles on it and see if it does anything the same as mine (see if the problem is me being crazy or if theres really something wrong) do you think such a specific request would be odd to them?

 

[Alec]

I think that's a good idea. Just look around the lot first and try to find one close to yours. I think you should take another car when you go to do it, and don't ask for such a specific model, just say a pre-2002 X or Mounty with the V8. You'll be able to get a feel for the truck even if it has AWD and different options.

 

[Alec]

BTW Darkfox,
One of my friends had a 96 5.0 2wd a while back. When I had my airfilter, exhaust, and chip, we were dead even.

 

[STANN]

When I took mine in for an oil change to a dealer in CA they said, "You know, you're not supposed to put a large supercharger or nitrous on your 4.0."

jerk.....just kidding

Thanks for the advice- good point about the torque converter. I dont really think its a big enough problem to take it to be checked out by a shop, and anyway I have zero cash for stuff like that now. I dont know about the computer- I didn't reset it but it has adapted to my admittly lead-foot driving style pretty well by now. Maybe I'll reset it though, and see what happens...
Any thoughts on if it might be a dirty MAS?

 

[Alec]

never hurts to clean the MAS. Maybe the filter wasn't installed perfectly and the MAS got some oil on it?

 

[STANN]

just use throttle body/ air intake cleaner on it, right? a q-tip also?

 

[X24]

Why would the torque converter lock up in 2nd gear at WOT??? It wouldnt. It would proceed to redline and shift hard into 3rd. When I've got it floored, I wont hit lock up until 4th at the earliest. Sometimes, if it's not locked up and I floor it, it locks up for a second and then unlocks and then downshifts a second later. Keep in mind I have the SOHC with a 5 speed tranny so all of what I said might not pertain to your situation.

Is brake cleaner OK to use on a MAS?

 

[psychotic]

I've had this same thing happen, only it wasn't after i installed my fipk, it was when i took it off to install sheet aluminum around it. I think maybe some dirt got in it . I dunno, it hasn't done it the past few days. It only occurs at WOT, and when its around 4k rpms.... esp if its after a downshift, the rpms seems to drop maybe 500 then pick back up. By the way, my aluminum flashing heat shield with aluminum dryer hose 'ram air' lowered my 0-60 from ~12 sec to ~11 sec

 

[STANN]

You seriously dropped 1 sec off your 0-60 time? How did you time that? Most impressive.

 

[Alec]

Most likely SOTP performance gain

(seat of the pants)

 

[psychotic]

no.. seat of the pants gain was from my hyper white signal bulbs I actually timed my 0-60 with my cd player. it was a lil over 12 before, now its consistent at a lil over 11. I took aluminum flashing, just put two cut piece in and put the bolts on my fipk through holes in the flashing to hold them together... duck taped it up some . Then i took 4 inch aluminum dryer hose, scraped up my hands a whole whole bunch and managed to get it from the opening in the plastic next to the fog like up to a hole in my aluminum "Heat shield". I also took a small piece and ran it from the heat shield to a spot behind and off to the side of the headlights. With a very accurate "stick hand in different spots" test, i have concluded that the aluminum does absorb header heat, cooler air does enter the dryer hose, and the air temperature around the filter is at least a few degrees cooler than the air temperature on the other side of the heat shield. if i stop being so lazy i'll take some pictures. I haven't even taken any pictures since i lowered it... argh i'm lazy.

 

[STANN]

well........the random RPM drop finally decided to go all out last night.....tranny blew- the infamous flashing O/D off light, the whole shoot-and-she-bang (i'm glad i fit that saying in somewhere ) anyway, tranny's totally gone, had it replaced before less than a year ago...arrggh. Unless the tranny is covered under warranty, it might be time for the X to depart....
Anybody think the RPM drop and this are related?

 

[Jason_25]

I have heard of the torque converter causing an RPM drop and stalling. But I would certainly hope that's not what is happening here.

 

[fordkrazy]

use non clorinated brake fluid to clean the MAS and dont touch the filimants w/ anything. dont spray it too close cause if you break a filimant your car wont run....and you will be forking out over $100 bucks for a new one......as far as the RPM drop....my tranny needs a lesson on how to shift as well.....but try reseting the computer....im sure that will help....but you have to be sure to baby it for about a week and let it idol for a good while before you drive it.