Fail safe mode?

[JFRAC_92]

I'm pretty sure some one has made a thread, but I'm lost here.. Working on my dads 05 ls 3.9, a couple days ago it had a hesitation at 3.5k, fail safe mode, code was for the TPS. Changed that out, had to unbolt the throttle body motor. Next day it had a coolant leak almost like it was coming from the degas tank. Re-burped the system leak was gone. Now it has a leak again I can't find it but now it's going back into ETC fail safe. If anyone can lead me in the right direction it would be great.

 

[LS4me]

I'm pretty sure some one has made a thread, but I'm lost here.. Working on my dads 05 ls 3.9, a couple days ago it had a hesitation at 3.5k, fail safe mode, code was for the TPS. Changed that out, had to unbolt the throttle body motor. Next day it had a coolant leak almost like it was coming from the degas tank. Re-burped the system leak was gone. Now it has a leak again I can't find it but now it's going back into ETC fail safe. If anyone can lead me in the right direction it would be great.

Escondido??? DUDE, I live next door in San Marcos!!

My wife's LS had the same fail-safe issue. Trust me here, it is NOT the throttle body. It is the #4 coil failing and causing interference with the PCM. When was the last time, if ever, you changed the plugs and coils? Start there.

Where is the leak? Behind the driver's wheel? That would be a cracked degas bottle and would need replacement.

 

[lexmarkz00]

Happened to me a few months back (fail safe mode), took it to the dealer and was told I needed a new throttle body.

 

[joegr]

Happened to me a few months back (fail safe mode), took it to the dealer and was told I needed a new throttle body.

Yes, and they are almost always wrong about that. Change all the coils and plugs first. RFI from marginal coil(s) will trigger false throttle body codes.

 

[mlara1129]

Yes, and they are almost always wrong about that. Change all the coils and plugs first. RFI from marginal coil(s) will trigger false throttle body codes.

so what are some indications that it could ACTUALLY be the throttle body? I recently replaced all coils and plugs and have had ETC fail safe come up 2 times. No noticeable misfires, and drives "OK" for the most part.

I may need to start a new thread, this is only part of some strange behavior in recent months from my LS.

 

[Telco]

...this is only part of some strange behavior in recent months from my LS.

Strange behaviour across different, unrelated systems can also be traced to an electrical system problem. I would have the battery load tested, and check all grounding to make sure there's no corroded grounds on the body/engine, engine/battery and battery/body grounds. It may even be worthwhile to have the alt tested, which can be done on the vehicle at the parts store. Rule that out before doing a time consuming system by system repair attempt that will fail if the ultimate cause is primary power related.

 

[stugots]

so what are some indications that it could ACTUALLY be the throttle body? I recently replaced all coils and plugs and have had ETC fail safe come up 2 times. No noticeable misfires, and drives "OK" for the most part.

I may need to start a new thread, this is only part of some strange behavior in recent months from my LS.

2003s could be the exception. There actually are some problems with the tb.

 

[Gus_Mahn]

Change the spark plug boots (about $6/ea) and spark plugs. If there is oil in the plug hole, change the valve cover gasket.

 

[1nastyls]

Try cleaning the throttle body it helped mine when it went into failsafe

 

[JFRAC_92]

Sorry been busy working on other jobs, found out the problem... There was a leak on the housing for the engine coolant temp sensor, and fixed it, and the problem went away. Thanks for all your help.