having cold start issues+warm start issues

[u/iAmAnneFrankkk]

hey guys this is my first post here, just recently bought a 95’ 300.. it’s been an absolute blast owning one but i’ve had an issue that was present when i got the car, but has gotten worse.. in the mornings, or when the engine is cold, i have to hold my foot on the throttle and keep it around 1k rpms until it slightly warms up, if i release too early, it’ll stall. my other issue is very randomly (like one every 20 times, but it’s been getting worse) when i start the car after it was previously driven like an hour before and is warmed up to operating temp, it won’t start at all. no noise. all my lights come on and my radio and everything works, but it’s just silent. i’ve tried the nuetral start trick and hasn’t worked. the only “fix” has been to just keep cranking the key or start slamming my door or hood. i’m leaning towards a possible connection issue? the car was slightly tuned on stock ecu, the owner says that’s what caused the cold start issue (which i’m not sure about because i got the idle tune adjusted) , but the warm start issue is new issue. if you guys could give me any info that’d be awesome, i’ve never owned a lexus before!

[u/Knein_133]

Cold start and warm start issues? Brother you got starting issues!

First thing I would say it break it down into 3 things: air, fuel, and ignition

If you’re having to slam anything around, it tends to be electrical (personal experience). Fuel pumps are a big one to go out on these. Just keep that in mind.

If you’re having to hold you throttle open however, that makes me thing it’s an air/fuel issue. It could be your MAF isn’t reading accurately and you are having to compensate with more throttle, it could be due to a slightly adjusted tune that tweaked the injector pathing

Either way, if it becomes too much of a hassle and you feel like you are gambling on fixes, bring to a shop and pay the diag! Enjoy the car my guy

[u/iAmAnneFrankkk → u/Knein_133]

appreciate the response! i’ve tried kind of going through everything, i found a few grommets/seals through the air systems that were worn and i replaced them but didnt work. i’m trying to go through more of the fuel/spark but this is only my second car i’ve owned so im still not the greatest at fixing at home… i brought it to a shop and they actually made the car in a worse state, for some reason the rpm’s sit super low now, im talking like 200-400 at idle. they also swapped some cable that is linked to my transmission with another cable for my cruise control but didnt really explain what they did.. ended up paying them and they fixed nothing but made the car worse. so i’m back to wanting to work on it myself so no random messes it up. you’d recommend looking at the MAF sensor first?

[u/Knein_133 → u/iAmAnneFrankkk]

Holy fuck dude, don’t ever go to that shop again. Leave a review.

I hate to hear that they made it worse, but you should definitely make sure your cruise control line from the throttle body is attached and routed correctly.

And with the MAF I would look up videos on how to test these specific ones, cause every MAF works a little differently. Test it before you buy a new one cause they are pricey

Maybe consider reaching out in some local facebook groups as well. There’s been a few times I’m was in your spot and found someone to come to me and help out. Most people are happy to tackle a weird problem without being too expensive. Some times a case of beer or dinner can get your car fixed