OKSTANCE

just put in gas and charged the battery. its only had a tuneup, fuel filter, and new ecu caps done thus far.

car cranks and will sputter like its trying to start ONLY while key is engaged which i hate doing to my starter...

any ideas? drove it last week without any real issues to speak of


tried to search but couldnt get the wording right to find anything useful - THANKS!

Legender

Might need some more details here...
year, model, miles....
First thing is retrace what you worked on and make sure you hooked all things back up. Doublecheck. If it worked fine prior to these changes then something didn't get put back right...or .... assuming it worked fine prior to the work... or it worked find post the work was done, but now all of a sudden this week it's having problems. Not sure of your description here.

OKSTANCE

okay well as you might guess its a LEXUS...LS400...
has 133k on it.

but more on the relevant details...
no recent work done the past 3+ months other than replacing wheel studs
had an issue with efi relay before that but just swapped it out and has been fine

Legender

Car needs three things to run.... fuel, air and spark... have to figure out which one you don't have.
Maybe the EFI relay has gone bad again. Why did it go bad the first time?
Does it start if you spray starter fluid in the throttle body and then die? That means it's got spark. and may point to a fuel problem. Did you get gas recently?
I got bad gas once in my old Avalon... wouldn't light if you soaked a paper towel in the stuff. Had to drain and start over. Chevron would not have anything to with helping me and that's the only gas I used to use. Guess where I never stop now?

OKSTANCE

specifically looking why it only stays running [sputtering/limping] while key is turned
otherwise its just like its out of gas which it has 3-5 gallons in it

timmy0tool

iTrader: (7)

year of the car is what we really wanted and mileage. from what i remember you have a UCF10.

so you have to hold the key on starter engage for the motor to keep on? i don't quite understand what you mean about the key having to be engaged. what happens when you try to floor it when starting?

might be a bad or defective AFM. do NOT try cleaning it. read here why, post #13:
https://www.clublexus.com/forums/ls4...and-maf-2.html

OKSTANCE

exactly! makes no sense =|
hmm yeah maybe could be air related because sometimes itll bog down

dicer

First thing to check is if while the key switch is on the ignition or run position that it has continuity, I have not checked to see if it passes off the contact while in the starter position. Don't have my info at hand right now. But I think ignition power can be checked at the service terminal at the engine. There is an igniter test that can bedone as well. Something could have come loose in that ECU also. Need to check the various signals that are necessary for the engine to run.

bgalarpe

I'm leaning toward a fuel problem...do what Legender recommend and try some starting fluid but it might be bad plugs if it wasn't replaced.

cobalt91

Spray a little starting fluid into the throttle body and try it. If you have spark and compression it should start.

OKSTANCE

hmm threw in a different battery and starts right up..oddly
but check eng light is flashing and feels like its missing..how i wish i had OBII =[ haha

dicer

? So what year? OBD1 you don't need a code reader. Or you wish you had an OBD2 reader?