CEL if I don't warm up engine

Hello I have checked in the 1 gen for similar issues that i have but have not found any threads. I have a 2002 4 cyl 2.7 230k Tacoma. I always get a CEL pop up if I don't let the engine warm up at cold start. I used to live in NY so I figured it was the cold weather. In Oct. I drove the taco to FL with no issues. And am currently living in FL. The other night 60 degrees outside I started the truck and did not warm up the truck like I usually do and CEL popped up. I will look up the CEL code today. Is it normal to get a CEL on these engines if they haven't been warmed up?

 

Do you know the code? Do you have a heated o2 sensor?

 

Forgot to mention parts that have been replaced when doing maintenance/service
Tranny oil
Motor oil,filter
Spark plugs
Air filter, fuel filter
Brake fluid, AC compressor, all belts, oxygen sensors 1and 2
EGR also
Engine is stock

 

I will look up the code later today. And I don't have a heated 02 sensor

 

The taco engine starts and runs fine even when CEL pops up when I don't warm up engine.

 

P0402

 

Code is p0402

 

@Glamisman @Speedytech7 @mechanicjon
When's the last time you did a valve adjustment?

 

@Dalandser I don't think it has ever been done.

 

I am going to replace the egr vsv

 

One channel I've been watching on YouTube lately is South Main Auto - he doesn't do a lot of Toyotas, but he's got a good diagnostic process on vehicular issues. I remember at least one diagnostic video on egr where he traced the problem without replacing any parts first. I like his videos for that reason. He's got a lot of experience that help him in his diagnostics but you can see the patterns of the processes he tends to follow and be able to see how to test for issues prior to spending any money on parts. It's one of those things that are easier said than done of course, but it's possible and there's a lot of scanning tools that are more and more affordable these days and a lot of videos on how to diagnose with a test light for electrical issues which seem to be the cause or part of the diagnosis in 90% of CELs.

https://m.youtube.com/channel/UCtAGzm9e_liY7ko1PBhzTHA

 

What O2 sensors are you running that don1`t have heaters?

 

Summer 2015 I had a whole new head built and it was obviously adjusted haha.

 

How old are your 02 sensors?

 

if your scan tool has the capability of monitoring engine coolant temperature (ECT) and closed loop, I would look at that. I can recall reading somewhere where during the warmup cycle (open loop), EGR is disabled for drivability. The PCM might not be receiving the correct signal and you are running around in open loop. As always... difficult to diagnose over a laptop screen.

 

@Wyoming09 I'm running the stock oem o2 sensors

 

@jrallan26 02 sensors there at least 2 years old but I had this issue from when I bought the truck.

 

@Glamisman thanks for the info I have a easydiag obd2 scanner that connects to my cell through bluetooth I pretty much use it to check/clear the CELs...i have replaced the EGR valve, EGR vacuum modulator... I haven't replaced the EGR vsv or the EGR TEMP. sensor both are original...

 

Based on what I read here:

https://launchtechusa.com/easydiag2plus/

You should be able to watch the live data and see if the coolant temp and closed / open loop are working the way the should.