2-3 shift knock

[Shimy87]

Messing with kids car again. Seems like at the 2-3 shift the car is sensing knock. 1-2 & 3-4 are smooth but 2-3 is harsh. I dropped tranny pan to confirm tv cable is adjusted correctly. Any ideas what else this might be??

[nocooler]

Is the converter locked in 2nd gear before the shift?

[Shimy87]

Nope

[Shimy87]

Could it be the rear end. If I remove the driveshaft how much "play" should be there? Like if it is engaging the gear at a marked 12 o'clock forward, how far backwards should I turn it before it engages backwards...if that makes sence

[Scoobum]

Post the PL file.

[Shimy87]

Don't have a logger for this car

[Steve Wood]

If the 2-3 shift is hard, I am guessing that the ecm is pulling timing because it heard that thump, or maybe felt that thump is a better term.  Other than being sure the engine mounts and tranny mounts are in good condition followed by making sure the idler pulley is not hitting the AC clutch and the exhaust is not hitting somewhere along the line from the upper A arm back thru the rest of the run, I guess live with it.  If it's not slipping, I don't think I would spend any money on the the transmission at this time.

[1 RARE T]

You could be on the raged edge of lean and the load from going into 3rd gear is too much.

[Shimy87]

Thanks guys!

[Shimy87]

Mark put new motor and trans mounts in car but they are cheap so replacing them. We just put a Pypes dual exhaust on the cars and no clearence or hitting issues there.

[Steve Wood]

Video the scanmaster as it shifts into third.  If it shows timing retard and then immediately goes away, it is most likely just hearing/feeling the shift.  If it hangs on and diminishes more slowly, it might be lean on the shift. 

Watch the timing retard and O2s on the video.

[Scoobum]

Don't have a logger for this car

PL is cheaper than changing headgaskets. Guessing is never a good idea.

[Shimy87]

The video is a great idea

I know a PL would be good but I like to live dangerously

[Scoobum]

The video is a great idea

I know a PL would be good but I like to live dangerously

I have vids on how to change head gaskets.

[Steve Wood]

The video is a great idea

I know a PL would be good but I like to live dangerously

Assuming you are running your usual near stock boost levels, this should work fine.  You might say "Now" when it shifts so you can go back and better pinpoint the shift point as it will be about one frame before you hear "now" (or maybe  less since you are younger and don't have thought to mouth lag like me.