Lurch and RPM spike when coming to a stop

New owner of a 2005 DC 4X4 limited and I’ve been noticing some issues that I’ve been trying to troubleshoot/resolve. When I first start driving and come to a stop the RPMs drop to an idle and then jump up causing a bit of a lurch forward. It will only do this the first couple times I stop so as something warms up it goes away. My first thought was a stuck slip yoke so I greased that as well as the rest of my driveshaft. When I took it for a test drive after that when I came to my first stop the engine died as it came to an idle. It fired right back up and I drove it home. There was a code for the upstream O2 sensor which could be because it’s going bad or because it actually read an out of spec fuel to air ratio. I cleaned the throttle body and the MAF and test drove it but no change was seen. I also checked the brake booster vacuum hose thinking maybe that was leaking and chocking the engine air but it appeared to be good and not clogged. I’m still suspecting(hoping) this is a fuel/air issue so I’ll record short term fuel trim while this is happening. Seems like if there’s a dip or spike when this happens then that should be a good indicator.


The other issue, that I’m not sure if is related or not, is a slight shudder when shifting around 45mph (4th to 5th I believe). I’m guess this is a torque converter issue so I did a fluid replacement hoping to fix this but I’m expecting a forthcoming transmission replacement. I’m not sure if this is related to my lurch when coming to a stop issue. Seems like it should not be but I figured I’d include this info.


Any thoughts? I’ve searched the forum and the internet and have come up relatively empty.

 

Well, the upstream 02 sensor is extremely important to basic engine function so fix that right away before trying to figure anything else out.

 

Read this thread: https://www.tundras.com/threads/so-you-wanna-buy-just-bought-a-1st-gen-tundra-eh.115928/

Tell us:

• How many miles are on the truck,
• if it was ever used to tow frequently or really heavy stuff,
• major maintenance, including how long ago the timing belt was done,
• any parts replaced before this began.

Vibration-wise ....

I doubt seriously your trans is dying even if 400k miles, if this was a GM I'd have a way different mindset. When you swapped fluid in your sealed transmission, did you follow the correct procedure to bring it up to operating temp, and confirm a few drips are coming out of the fill hole? And what color was the fluid that came out? Black? Brown? Ruby red?

Beyond that, when was the last time you greased your driveline, especially your slip yoke, which has a weird procedure required? It's due every 5k miles. Most people never do it. It causes a ton of clunks, thunks, and vibration eventually if you don't. More details available in the thread I linked.

Surge-wise ....

Unless you want a much more expensive problem, if it's actually the O2, you'll want to swap it out. Sure, could be a leak - intake manifold, exhaust manifold, vacuum - or it could be an O2. But if it's an O2 sensor, you may be looking at a clogged cat soon, which is $$$$$

For O2 sensors, MAF, coil packs, fuel pump, starter, relays and other electrical stuff you DO NOT want to use store-brand parts. Only Denso. I know, this sounds like bullshit. It's not. Stick around here for a year or two and you'll see for yourself how many problems result from aftermarket parts OR genuine-looking counterfeit parts someone bought on scAmazon or fleaBay.

 

https://www.tundras.com/threads/messed-up-my-transmission-a-warning-to-everybody.117835/

My engine wouldn’t die but if I had a quick stop my RPMS would drop and then I got the lurch. Then I blew up the transmission. I changed out the transmission (didn’t do anything else to the truck) and problem solved. No more lurching at a stop. Not saying this is definitely your problem but it is a possibility. I would do all the low hanging fruit first through. (Clean MAF, change the O2 sensor, lube drive line and look at transmission crossmember)

 

It has 182k miles on it but I just bought it a few weeks ago so not 100% sure of it's past use. There were a lot of records of it being serviced at a toyota dealership very consistently over the years. It appears it was used for towing but no clue what was towed with it. Timing belt was done at 92k miles so it's due for a replacement now. I just got all the parts in to start that. I haven't replaced any parts since again I just bought it.

When I did the fluid transfer I followed the procedure, waiting for it to get up to temp which I checked with my scanned and waited for a small trickle. The fluid that came out actually looked quite good. I was honestly hoping it would come out just black and the new fluid would make a big difference. It seems it was replaced quite recently.

As far as driveline I just greased it last weekend using valvoline NGLI2 grease.

The O2 code (P2241) was actually a stored code when I bought it so perhaps this has been ongoing or intermittent at least. I just got in new Denso upstream and downstream sensors that i'll be putting in shortly. I previously had a '99 4Runner so I've learned the hard way that OEM is required for nearly everything. Unfortunately that 4Runner had the ole strawberry milkshake which ruined the TC and required a new tranny. Hopefully I'm not having bad luck with these Toyota transmissions.....

 

I actually just read your thread yesterday. It definitely made me a little nervous haha. Hopefully it's something simple.

Hows that used transmission working out for you now?

 

Sounds like a good enough reason to go ahead and replace the rad on this truck when you do the timing belt.

 

Sounds like It could be the TPS - throttle positioning sensor.

There was a recall back in the day for Gen 1s if I remember correctly.

 

The new (to me) transmission is working awesome. I immediately noticed a difference. Much faster and crisper shifts. It did for the first bit have a little too aggressive of a downshift from 3rd to 2nd. I was a little worried so I did some research on the transmission “learning.” Found a website (might have been Sonnax or something like that) that said up to 04 removing the battery cable for 30 minutes will reset the learning. 05 and later it actually has to be plugged in and reset, or just driven long enough to relearn. I choose to just drive it. After about 2 weeks the aggressive downshift went away and now it’s perfect. Feels like a younger truck!

 

Definitely. Not taking any chances with that.

 

The idle drop and lurch sound like a sticky torque converter to me. Tranny fluid level and color, good and good?

 

Hmmmmm………Sticky torque converter……maybe that’s what was plaguing my truck? (P2757 lockup problems and also the lurch) I still have the old transmission and torque converter in my garage. Is there anyway to inspect the converter easily? Just out of curiosity mostly to see what the problem actually was.

 

Look at '(c)'

 

Interesting. When I get a chance I’ll do that test. Looks easy enough.

 

Well I replaced the O2 sensors on bank 2 and have been driving it to work all week and that seems to have fixed the issue. It seemed like there was still a slight RPM spike but no where near what it was before. I think that’s even gone away as well, maybe it completed a full relearn with the new sensors. I’m also pretty sure the shudder is gone as well which I’m guess was the transmission fluid change. I’ll update if either the lurch or the shudder returns. Thanks for your help everyone!