gs300 Idle/Start up problems
Thread Starter
Driver School Candidate
Joined: Dec 2012
Posts: 17
Likes: 0
From: IL
gs300 Idle/Start up problems
Hi,
Hoping you can point me to the right part...
I have a early 99 GS300.... feels like its running on two cylinders for the first 5 sec after start up.
When I crank it , it takes 5-6 rotations to start.. then it runs so rough that it dies.. When I try again it just comes on and runs fine. Every morning this is the ritual.. Car never dies when running but feels like there is no fuel in the lines every time I try to start it..
I changed the starter,alternator,battery,fuel pump,fuel filters,fuel pressure regulator, spark plugs and wires.. I am down to coils or injectors.... don't know what it can be....
Any ideas? got no check engine light... no codes...
Hoping you can point me to the right part...
I have a early 99 GS300.... feels like its running on two cylinders for the first 5 sec after start up.
When I crank it , it takes 5-6 rotations to start.. then it runs so rough that it dies.. When I try again it just comes on and runs fine. Every morning this is the ritual.. Car never dies when running but feels like there is no fuel in the lines every time I try to start it..
I changed the starter,alternator,battery,fuel pump,fuel filters,fuel pressure regulator, spark plugs and wires.. I am down to coils or injectors.... don't know what it can be....
Any ideas? got no check engine light... no codes...
Thread Starter
Driver School Candidate
Joined: Dec 2012
Posts: 17
Likes: 0
From: IL
not yet, think I have some vortex kind you cant clean.....not sure...
just surprised its not throwing a code ,
now it feels like starting a carbureted engine with a vacuum leak in 0°F
is it possible that somehow i still don't have fuel during initial start up after I replaced the regulator and pump? If I give it gas right as I am starting it will crank on and maintain idle...
not sure if at this point I can rule out injectors and coils... I do have 180K on them but once on car runs fine..
I was told it might be the IAC valve...
just surprised its not throwing a code ,
now it feels like starting a carbureted engine with a vacuum leak in 0°F
is it possible that somehow i still don't have fuel during initial start up after I replaced the regulator and pump? If I give it gas right as I am starting it will crank on and maintain idle...
not sure if at this point I can rule out injectors and coils... I do have 180K on them but once on car runs fine..
I was told it might be the IAC valve...
Rookie
Joined: Apr 2013
Posts: 73
Likes: 0
From: Ny
gs300 does not carry an iac valve but rather an idle control motor right next to the tps sensor. your tps sensor may be bad. might have to open it and check it. it has to be properly set with a scan tool. if its not than get a toyota mechanic to come evaluate whether the idle motor need replacing.....
Thread Starter
Driver School Candidate
Joined: Dec 2012
Posts: 17
Likes: 0
From: IL
thank you... at this point I just want to eliminate if its fuel/spark..ect obviously its not compression and most likely something electrical...
Ill check the tps ,idle control motor,
(but would that explain my original starting problem/delay...?)
problem started by having to hold the ignition on for 4-5 sec for it to crank over.. starter and battery are new so it seemed very delayed almost like spark or fuel was missing... now that developed into rough idle /misfire right after....
Timing belt was changed 30K ago... looks good...
no leaks, fuses look ok,
thanks again
Ill check the tps ,idle control motor,
(but would that explain my original starting problem/delay...?)
problem started by having to hold the ignition on for 4-5 sec for it to crank over.. starter and battery are new so it seemed very delayed almost like spark or fuel was missing... now that developed into rough idle /misfire right after....
Timing belt was changed 30K ago... looks good...
no leaks, fuses look ok,
thanks again
Instructor
Joined: Dec 2002
Posts: 1,043
Likes: 31
From: CA
i think the fuel pump or fuel filter replacement maybe messed up, so it's not holding pressure. Did you DIY? or pay a mechanic?
Try this:
After a cold soak when you'd have the problem; put the car in ON position for 1min before starting it, to see if that gives the fuel pump to build pressure back. If that works, then that means it's your fuel pump/fuel filter install.
If you did do a DIY on the fuel filter, i might know which step you messed up, related to an o-ring, because I did the same thing too.
Try this:
After a cold soak when you'd have the problem; put the car in ON position for 1min before starting it, to see if that gives the fuel pump to build pressure back. If that works, then that means it's your fuel pump/fuel filter install.
If you did do a DIY on the fuel filter, i might know which step you messed up, related to an o-ring, because I did the same thing too.
Thread Starter
Driver School Candidate
Joined: Dec 2012
Posts: 17
Likes: 0
From: IL
Thank you, appreciate it.
I will check timing ,oil control valve next... car ran fine after timing job( mechanic) for year didn't give me any problems until this.. Ill try to jump it and see how it starts if I leave it ON for a while before cranking over..
I did the strainer ,fuel pump, fuel filter, pressure regulator all at once via Denso fuel pump kit.
all new gaskets and rubber o rings also new fuel tank gasket... right after I did it car showed no sign of improvement ... runs the same like it did on the old 180K original Toyota pump and filter...
again thanks for the help,,, I was thinking its injectors or coils... now got a whole buffet of stuff to check... cant wait to start... 5'F in Chicago...yey
I will check timing ,oil control valve next... car ran fine after timing job( mechanic) for year didn't give me any problems until this.. Ill try to jump it and see how it starts if I leave it ON for a while before cranking over..
I did the strainer ,fuel pump, fuel filter, pressure regulator all at once via Denso fuel pump kit.
all new gaskets and rubber o rings also new fuel tank gasket... right after I did it car showed no sign of improvement ... runs the same like it did on the old 180K original Toyota pump and filter...
again thanks for the help,,, I was thinking its injectors or coils... now got a whole buffet of stuff to check... cant wait to start... 5'F in Chicago...yey
Last edited by sidehide; Jan 15, 2014 at 03:15 PM.
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Instructor
Joined: Dec 2002
Posts: 1,043
Likes: 31
From: CA
Yea, if the ON positin test works, and it turns out it's the fuel pump system:
For the o-ring on the fuel filter.
If you followed the DIY in this forum with pictures, it had a step wrong, which said just throw the o-ring on top of a tube(like a faucet gasket) and then put the 2 parts together.
This O-ring is not a top-bottom "gasket", it is an interface which separates the inner and outer circles of the ring. You need to ensure the o-ring is slid onto the tube (lubricated with fuel), before putting filter and pump together. The putting together the filter to pump should be a friction-tight fit, that doesn't come apart if you were just holding it in the air just by one of the parts.
For the o-ring on the fuel filter.
If you followed the DIY in this forum with pictures, it had a step wrong, which said just throw the o-ring on top of a tube(like a faucet gasket) and then put the 2 parts together.
This O-ring is not a top-bottom "gasket", it is an interface which separates the inner and outer circles of the ring. You need to ensure the o-ring is slid onto the tube (lubricated with fuel), before putting filter and pump together. The putting together the filter to pump should be a friction-tight fit, that doesn't come apart if you were just holding it in the air just by one of the parts.
Last edited by raytseng; Dec 12, 2013 at 09:51 AM.
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Thread Starter
Driver School Candidate
Joined: Dec 2012
Posts: 17
Likes: 0
From: IL
Fuel pump and regulator are fine..
Got a TPS and OCV valve that I am about to put in, hope it works, already changed the MAF but it did nothin..
Got a feeling its something with the throttle body assy... unless I have a bad cam/crank sensor but then again no CEL..hmmm
Got a TPS and OCV valve that I am about to put in, hope it works, already changed the MAF but it did nothin..
Got a feeling its something with the throttle body assy... unless I have a bad cam/crank sensor but then again no CEL..hmmm
Lexus Test Driver
Joined: Feb 2012
Posts: 1,158
Likes: 23
From: PA
If everything you say you replaced was properly installed, then the only thing left to try is a good MAF sensor + throttle body clean... Try that bro... Really.. And let us know how everything turned out!! Good luck, stay positive, and everything will work out for the better my friend!!!
Thread Starter
Driver School Candidate
Joined: Dec 2012
Posts: 17
Likes: 0
From: IL
If everything you say you replaced was properly installed, then the only thing left to try is a good MAF sensor + throttle body clean... Try that bro... Really.. And let us know how everything turned out!! Good luck, stay positive, and everything will work out for the better my friend!!!
Bought a new TPS sensor and put it on right and it made it even worse,, got a CEL and put the old TPS back on.
My throttle body assy # is 22030-46150 but I hope I dont have to get the whole thing because only ones for sale used are 22030-46220, or 22030-46180 , or 22030-46120 from different years GS and IS like 2000 or 2002...
Lexus told me they are not sure if those will work even tho they are bolt on from same engine and model...
Last edited by sidehide; Jan 20, 2014 at 01:12 PM.
Driver
Joined: May 2013
Posts: 114
Likes: 0
From: Arizona
you might also have leaking injectors. They might be leaking when the car is not running causing you a lack of fuel pressure when you try to fire it up, and since their is now fuel in the cylinder from the leaking injector(s) it will cause it to run rough at first until the excess fuel is burned away or blown out the exhaust. Its fairly cheap to get the injectors cleaned and flow tested to make sure they are up to spec, or for piece of mind you could just replace them. the local place by me is about 20 bucks an injector to clean and flow test, and its usually finished the same day. I would pull the spark plugs after letting the car sit overnight and inspect the cylinders for wetness and strong fuel odor the next day before you even fire the engine up. Seems like you might have replaced everything else already, and this is a commonly overlooked problem.
Thread Starter
Driver School Candidate
Joined: Dec 2012
Posts: 17
Likes: 0
From: IL
you might also have leaking injectors. They might be leaking when the car is not running causing you a lack of fuel pressure when you try to fire it up, and since their is now fuel in the cylinder from the leaking injector(s) it will cause it to run rough at first until the excess fuel is burned away or blown out the exhaust. Its fairly cheap to get the injectors cleaned and flow tested to make sure they are up to spec, or for piece of mind you could just replace them. the local place by me is about 20 bucks an injector to clean and flow test, and its usually finished the same day. I would pull the spark plugs after letting the car sit overnight and inspect the cylinders for wetness and strong fuel odor the next day before you even fire the engine up. Seems like you might have replaced everything else already, and this is a commonly overlooked problem.
Remind me whats the point of owning a lexus again...... I could have and less issues with a chevi ahahahahahah garbage... I am selling this car... Thank you for the additional help, I would have probably done the injectors next... ohh btw the power staring pump and the harmonic balancer broke too...
Lexus Test Driver
Joined: Feb 2012
Posts: 1,158
Likes: 23
From: PA
Don't blame the car, who was the previous owner and what kind of neglect was done to the car has to be taken into accountability, I can drive a Ferrari for 10 years and neglect it and will eventually start breaking down on me due to neglegience, doesn't mean it's a pos...