torque converter failure?

Messages
350
Location
austin, texas
Hi, i have a 2002 toyota tundra v8. it has 170k miles. two weeks ago the the transmission/torque converter were replaced (total failure two weeks ago). it has been driving extremely well these last two weeks since the replacement was done. however today the truck started to shudder. the shuddering happens in reverse and drive, not in park/neutral. you can feel the whole truck shake (not all the time, but maybe every 5-20 seconds). idling at a stop light while in drive is probably the worst. the transmission is naturally under warranty and i will be taking in thur morning. however i was wondering if it could be something else. i checked for codes with my obd-ii reader, there are none. vacuum hoses looked good too. i don't have equipment to check for clogged cat converter. atf fluid looks new (should be) and level is correct. also, i do not believe it to be bad gas as the last fill-up was a week ago and it has been fine until today (have about a qtr of a tank left). is it possible the dealer put the wrong atf in it? the atf changed from 2002 (dexron-ii) to 2003 (toyota type t-iv). this is a toyota re-manufactured unit. also, any of you think lubeguard (platinum) works? and if it does work, does it work forever (or until you change the fluid) or just a very short term fix. thanks!
 
Last edited:
Messages
737
Location
NC USA
It could be a trans concern. The torque converter solenoid can fail and allow hydraulic pressure to be applied to the converter clutch and cause a shudder at a stop. It can even cause the engine to stall at stops.
 
Last edited:
Messages
3,775
Location
Houston, Tex
Originally Posted By: Roadkingnc
It could be a trans concern. The torque converter solenoid can fail and allow hydraulic pressure to be applied to the converter clutch and cause a shudder at a stop. It can even cause the engine to stall at stops.
Is that solenoid normally closed or normally open on a Tundra? My experience (General Motors) is they are normally open. I would guess a broken motor mount, possibly caused by the transmission removal and installation process, or just a plain old engine miss.
 

mikeinaustin

Thread starter
Messages
350
Location
austin, texas
ok, now i am really lost. took it for a test drive and everything was fine while it was cold. once it warmed up, it would randomly "shudder" at a stop light (in gear, brake on). took it home and it did the occasional studder while going 30mph, but not much. once home i started playing with it. this is what i noticed : 1) when in drive but stopped AND the moment the a/c cycles on the 'shudder' would increase in movement and frequency. when i turned off the a/c the strength and frequency of the shudder would decrease (not totally eliminated). 2) put the car into neutral expecting zero shudder/studder. well to my surprise it still did. the strength of the movement was much much less but you could still tell it was occasionally happening. i really did not expect this at all. so now i am lost. the feeling would be like the engine was going to die (stall out) but catches itself and things continue normally. re-verified no engine codes exist.
 

mikeinaustin

Thread starter
Messages
350
Location
austin, texas
i need to be a bit more clear on this. even if going a steady 35mph down a road these "blips" will happen. you can feel the entire truck do a quick shake. i took off and cleaned the maf sensor. the air filter looked good. i have not attempted to clean the throttle body yet.
 
Messages
8,859
Location
Texas
Originally Posted By: mikeinaustin
ok, now i am really lost. took it for a test drive and everything was fine while it was cold. once it warmed up, it would randomly "shudder" at a stop light (in gear, brake on). took it home and it did the occasional studder while going 30mph, but not much. once home i started playing with it. this is what i noticed : 1) when in drive but stopped AND the moment the a/c cycles on the 'shudder' would increase in movement and frequency. when i turned off the a/c the strength and frequency of the shudder would decrease (not totally eliminated). 2) put the car into neutral expecting zero shudder/studder. well to my surprise it still did. the strength of the movement was much much less but you could still tell it was occasionally happening. i really did not expect this at all. so now i am lost. the feeling would be like the engine was going to die (stall out) but catches itself and things continue normally. re-verified no engine codes exist.
Thats sounding a lot more like an engine misfire than a transmission issue. Strange that OBD isn't catching a misfire, but I'd go on the hunt for all the usual suspects- plugs, wiring, coils, fuel pressure, vacuum leaks, etc.
 

mikeinaustin

Thread starter
Messages
350
Location
austin, texas
440Magnum is correct...possibly. dealer says it was a bad direct ignition coil (truck does have a lot of miles on it). the only thing that bothers me is no error codes are present (at least not with my obd-ii reader). maybe the toyota dealer has better scan tools to get more information out. which raises the question, if an ignition coil goes bad yet the computer does not detect an error, how is one supposed to diagnose this type of issue? i don't have spare coils in my house, so its not like i could swap out each one and see if the problem goes away. even worse, if 2 or more happened to go bad at the same approx. time... how do mechanics isolate this type of failure without an error code? also, do dealers have access to "hidden" error codes that the typical code reader that you and i can buy cannot access?
 
Last edited:
Messages
8,859
Location
Texas
Originally Posted By: mikeinaustin
which raises the question, if an ignition coil goes bad yet the computer does not detect an error, how is one supposed to diagnose this type of issue? <> how do mechanics isolate this type of failure without an error code?
Fall back on the old methods... volt/ohm meters, test lamps, and oscilloscopes. ;-)
 
Messages
8,859
Location
Texas
Originally Posted By: SteveSRT8
with no codes I seriously doubt a misfire exists. Newer cars are super sensitive on that one. I think this will likely be something else.
Possibly... but its in the realm of possibility. We're talking about a 2002 model not a 2010, and I firmly believe that misfire detection algorithms have gotten steadily more aggressive since the debut of OBD-II. My 2001 Jeep is not nearly as sensitive to misfire as I would have thought. It triggers the CEL when the #3 fuel injector vapor locks on a hot start-up (a silly and common problem on the 2000-2001 4.0), but it did NOT trigger a CEL when I had a very obvious misfire under load due to a bad spark plug (the one in a photo I've linked in a couple of threads about spark plugs).
 
Messages
5,020
Location
Southeast
is there a noise when it happens? Idle it, brake on, in gear. stand to THE SIDE of the car. Have someone keep foot on brakes. use a LONG stick to touch differnt parts of the engine and search for source of noise. if it's the AT, the sound will be strongest there.
 
Messages
5,020
Location
Southeast
TC failure or control solenoid failure will likely lightly jolt the car or bounce the engine in its mounts if it is catching in gear, at idle. you should be able to see it.
 
Messages
19,686
Location
Sunny Florida
Originally Posted By: 440Magnum
Originally Posted By: SteveSRT8
with no codes I seriously doubt a misfire exists. Newer cars are super sensitive on that one. I think this will likely be something else.
Possibly... but its in the realm of possibility. We're talking about a 2002 model not a 2010, and I firmly believe that misfire detection algorithms have gotten steadily more aggressive since the debut of OBD-II. My 2001 Jeep is not nearly as sensitive to misfire as I would have thought. It triggers the CEL when the #3 fuel injector vapor locks on a hot start-up (a silly and common problem on the 2000-2001 4.0), but it did NOT trigger a CEL when I had a very obvious misfire under load due to a bad spark plug (the one in a photo I've linked in a couple of threads about spark plugs).
You may be right. This could be a bit beyond that vehicle's monitoring capabilities if it's very subtle.
 

FZ1

Messages
4,735
Location
Texas
Look,if it did not have the problem,before they worked on the truck,then it's something they did,or replaced. I wonder if it could be a motor mount?
 

mikeinaustin

Thread starter
Messages
350
Location
austin, texas
just an update. the dealer did in fact replace a direct ignition coil ( 1 of 8 ). with this change, the truck runs fine again. there never were any engine codes present.
 
Top