For the past couple of days, my IS200T has been hesitating when I start the car and I'm hoping to get some wisdom from some of you on the forum. The car is a 2016 with the original battery so I'm a little suspicious of that but I'm also leaning towards a vacuum leak since I've heard that can cause rough startups. No check engine light.

It sort of sounds like a cammed car starting up and it settles back down after. I've also noticed an increase in burbles and pops when I downshift since this started happening.

I tried to attach a video of the start up but the file size is too big unfortunately.

Any advice?

 

If the vehicle is starting fine then that rules out the battery.

Any issues when it's driving? Initial thought was the vacuum regulator valve as per the attached TSB, but it only mentions an issue while driving, not on startup.

 

The car has been driving fine but I’ve noticed a different exhaust pitch and an extra “airy” noise coming from the front. I just chalked it up to me overthinking but it could be related?

I don’t think it’s the vacuum regulator because I’ve been replacing it every 10-15k miles and the car doesn’t have that hesitation it gets while moving like it does when the regulator goes bad.

I’ll try to get a shorter video later today so it meets the size requirement and attach it

 

My 2016 would hesitate starting as well when the battery started to go out a couple of months ago. It still started up for a couple of weeks until it died completely and car wouldn’t start without a jump.

 

I guess it will help when we can see what is happening at startup for the OP's vehicle.
If a car cranks normally and fires up, the likelihood of the battery being the issue is extremely slim.
The question would be, how would that differ from the way a good battery would behave at startup?
If the cranking seemed to be slow and weak, but the vehicle still started, then yes, the battery would be the first thing to check.

 

What you described really reminds me of what was happening with the E9x BMW 335i's with the HPFP / injector failure, especially how you mentioned the car sounded cammed on start.

Wasn't there a fuel pump recall that just came out for the 200t too?

 

The 2016 200t hasn’t been affected by the the fuel pump recall (yet...)

 

do you turn off car immediately after stopping?

 

Check the LT Fuel trims with an OBDII scanner. You will be able to see if the PCM is adding or reducing fuel to compensate for a vaccum leak or other issues.

 

A car "starting" does not rule out low voltage. Test your battery both with engine off and on. Should be around 11.8-12.2v off, 14.4-ish on..

Also you may want to check ST/LT fuel trims. A pattern of bad ST trim will eventually set off the CEL depending on how long this has been going on. If your LT trim is good but ST trim is bad, then this could indicate a vacuum leak or fuel issue.

I'd start by doing a visual check of the engine compartment to make sure you don't have any unmetered air ingestion aka vacuum leaks. Look for rips tears etc. Did you install any mods in the engine? check around these areas if you did.

 

I don't turn it off immediately but I don't wait too long either - probably around 10-15 seconds.

I've done a visual inspection and don't see any tears on any of the lines that are visible from the engine bay. I'll check the battery for now until I can get my hands on a scanner to also check the fuel trims.

Unfortunately even a short 3-4 second video is ending up too large and not allowing me to upload it.

 

Any resolution on this? I have a 2017 IS200T and it will turn over for 4-5 seconds before catching.

 

Did you get your problem solved? Mine is also having similar issue, 2019 IS300. 4-5 seconds before engine starts.