Slop in the MTX (Bucking at low speeds)

I'm afraid to find the answer out. I tried doing a search, but didn't find anything.

My tranny likes to buck a little when stuck in major rush hour traffic at low speeds. I'll tap the gas or I'll let off the gas and it'll buck a little. I think I read that the DMD helps a little (even though I know its an engine mod). My tranny has NO problems shifting in gear or staying in gear. Its smooth shifting.

Any ideas, suggestions, or mods to help me out?

im having a similar problem. I do have some tranny problems but I believe this one is related to a bad rear motor mount/roll restrictor.

I had something similar (I had to tap the gas lightly on 1-2 and 2-3 shifts). Cleaned the MAF and the problem almost went away. My theory is that when I let off the gas the RPM fell too fast due some MAF/IAC issue.
Also had very rough idle for the same issue, much better now.

One more related issue, drive at a steady 25-30mph in 2nd in slight downhill and quickly take your foot off the gas. It used to buck for me (same reason).

Tiv

i do have a rough idle..how do you clean the maf? I thought the sensitive??

Could also be C/V's

Wow, i always thought that was a consequence of getting a ford. Maf, uim and lim here i come!

Originally posted by TheGreatOne:
i do have a rough idle..how do you clean the maf? I thought the sensitive??

Yep, remove the MAF sensor. (comes right after the airbox and has a black rectangular top the size of a match box, held by 2 'security' torx screws).

Short procedure:

1. Disconnect ECU / battery / whatever to power it down
2. Disconnect MAF electrical connector
3. Remove 2 security torx screws (you'll need a T-20 (IIRC) bit with a hole in the middle)
4. Pull the MAF sensor, be extra careful, its fragile. Don't touch the sensor wires. It has 2 thin wires a bit similar of a light bulb's
5. Spray it liberally with a "O2 sensor safe" Carb cleaner until clean.
6. Dry it.

7. Put it back in reverse order.

T.

Couldn't you spray it while its still in the tube??

Yes you can.

Originally posted by Stazi the Aussie:
Yes you can.

Thanks, I'd feel safe leaving it in the tube and spraying the crap out of it.

Just a thought:
I have found the THF exadurates bucking in first gear.

Originally posted by mcciavarella:
Just a thought:
I have found the THF exadurates bucking in first gear.

Throttle Hang Fix?

I don't have it if thats what you mean.

1) DO NOT REMOVE THE SENSOR FROM THE HOUSING. Just spray it in place.
2) Use brake cleaner, or better yet electronics cleaner. Something that is residue free (and carb cleaner isn't it, O2 safe or not).

Didn't we talk about possibly using IPA as a cleaner before ?? Would a gentle swabbing do the trick as well ??

Originally posted by PA 3L SVT:
1) DO NOT REMOVE THE SENSOR FROM THE HOUSING. Just spray it in place.
2) Use brake cleaner, or better yet electronics cleaner. Something that is residue free (and carb cleaner isn't it, O2 safe or not).

After our conversation at E-Town, I wasn't planning on removing the sensor. I have a big can of electronics cleaner at home and planned on using that.

Thanks for the tips, guys.

Originally posted by TheGreatOne:
im having a similar problem. I do have some tranny problems but I believe this one is related to a bad rear motor mount/roll restrictor.

My rear mount is shot, too, and I have the same trouble. When the car is cold, I have to coast the car up to 3rd gear to mitigate the bucking.

In reply to:

My tranny likes to buck a little when stuck in major rush hour traffic at low speeds. I'll tap the gas or I'll let off the gas and it'll buck a little.

I've seen 2 other cars buck like that at low speeds just after clutch engagement due to a lean stumble, ie unmetered air leaning out the mixture on throttle tip in. Both cases were traced back to slits or cracks in the air intake hose which let in just enough unmetered air to throw off the whole combustion process.

That phenomenon could also result from MAF problems too, since a faulty or dirty MAF could give similar lean tip-in conditions.

I personally have noticed that the throttle hang fix has caused some throttle tip-in jerkiness, so maybe that is the issue here.

Don't swab - the less you touch the sensor elements, the better off you are. If you break one of them, it's time for a new MAF. If you leave cotton behind, then it's still contaminated. If you move one or both of the leads, the fine calibration done at the factory can be changed (each sensor is hot calibrated and laser trimmed on a flow bench during manufacture, AFTER the housing is attached to the sensor).

OK, yesterday morning, I went out and cleaned the MAF with Electronic cleaner (I kept it in the tube and sprayed through the screen). And since I had the tube off , I cleaned the TB's with some TB cleaner. I put everything back and took it for a test drive.

Something wierd is happening. I would pull up to a light or stop sign with the car revving a little high (~3K because I didn't feel like shifting). And once I pushed in the clutch at around 3K to coast to a stop, my car would stall. It happened a lot after I did the cleaning and then would do it less after the day went on.

Tonite, I pulled fuses 4 and 11 and did the idle-mild drive thing and it didn't stall. I HOPE that is my fix.

Originally posted by TommySVT:
I'm afraid to find the answer out. I tried doing a search, but didn't find anything.

My tranny likes to buck a little when stuck in major rush hour traffic at low speeds. I'll tap the gas or I'll let off the gas and it'll buck a little. I think I read that the DMD helps a little (even though I know its an engine mod). My tranny has NO problems shifting in gear or staying in gear. Its smooth shifting.

Any ideas, suggestions, or mods to help me out?

Thats exactly what my car did befor the differential went!!

Originally posted by TommySVT:
Tonite, I pulled fuses 4 and 11 and did the idle-mild drive thing and it didn't stall. I HOPE that is my fix.

Keep Us Posted!

Car doesn't stall now after the fuse pull. Idle is a little smoother. Car still bucks, but its much better than before the cleaning.

I wonder how hard it is to replace the transaxle mounts and add the poly bushing insert.

well, if i were to do it myself, I would get the car up on ramps, and get a floor jack with a piece of wood (to evenly distribute any weight) and put it up under the oil pan...no pressure so to speak, just snug it to prevent any movement. Then take the mount off and put he new one in. That's just me.