2002 LS dies when cold ok when warm

I start it cold then drive two miles, 1 in town 1 on the freeway. It is almost warmed up. For the last three days it dies when I stop at the light on the freeway off ramp, which is down hill. It always restarts but yesterday it run a little rough, some white smoke then it was OK. It runs normal when its warm.

No check engine or any lights. Today however I decided to let it warm up before I left the house. I'm in Arizona it was near 60 degrees. It idles slightly fast since it was cold. I went inside then when I come back out it died before it warmed up. It restarted & I warmed it up, no white smoke & never had a problem taking my usual route.

So it appears it is a cold problem until its warmed up. I have ohm/volt meter but I'm not sure what I should check? I spoke to a repair shop & he said maybe I should leave it over night & they would check it the next morning.

I would like to check what I can before I leave it with them. Can someone suggest some things to check. I'm very mechanical but limited on Fuel Injection & sensor problems. Thanks

Well, not liking the white smoke aspect of your problem.....

First thing in the morning, check the level of coolant in your reservoir.....also, remove the rad cap and check the level in the radiator.....

3.1/3.4/3.8?

Places like AutoZone will scan the car for codes for free....

Thanks, its a 3.8. Radiator is full & tank level is OK. I revved the engine near 4k in neutral when it died. It cut in & out maybe that had something to do with white smoke, never did it again. Eng only has 60k miles, great shape. Is there a rev limiter in neutral that causes it to cut in & out? I ask because its fine under acceleration at 4k.

I may try AutoZone but doesn't a trouble light have to go off to create a code?

Thanks again

Yes, there is a rev limiter in the programming of the PCM(computer)....

No, some times a code sets, but it has to fail 2X's in a row to turn the light on....if it only fails once, it won't turn the light on, but the code will be stored in history....

Could be a dirty IAC.....check the vac line to the fuel pressure regulator for fuel......could be MAF starting to act up......

I'll check for codes first & may buy some intake cleaner for Throttle body valve & clean IAC or replace if necessary - Its never been cleaned. Fuel regulator vacuum line was good, That was replaced some time ago. Will see about the MAF. Many thanks, will let you know.

This morning on a cold engine I got about 50 ft & it sputtered real bad. I tried to rev it with little success. It appeared to blow out darker color smoke, like it was running rich. Finally it cleared up, went about a block & it started sputtering real bad again. I let it sit a minute thinking some heat might transfer & help. It started right up & run fine.

Went to O'Rilley, they run a scan, no error codes. I bought some cleaner & will clean IAC & throttle body this afternoon. Just an update in case what I explained might help. Also I filled with gas about a week ago & all of this started since then. Maybe a coincident, I don't know what fuel additive might help if any.

I cleaned the T Body & IAC, wasn't real bad, I left the screen in. The IAC was seating in the TB all the way around. It runs fine so I will see what happens tomorrow on a completely cold restart & go from there.

It started & seemed OK, the fast idle dropped to about 1000 then it died. It restarted, no problems so I drove around a short block first.

Then I took my normal route to & on the freeway. At the base of the off ramp it died in the same place. It was at or very close to operation temp. After a restart it was fine, no problem the rest of the day. The clean up seemed to help but I will try it again tomorrow. I might have it checked again for any errors, just in case.

I'm just keeping a running track here until its fixed or fails or any other suggestions. Thanks

Unfortunately, you can't clean the throttle body by just spraying through the screen....

3 nuts/studs hold the throttle body on.....need a new gasket......coolant will come out on removal.....clean the throttle plate and bore from the rear.....can remove the IAC and really clean that passage out now.......

As I said, you can have a MAF starting to go on you......with the throttle body off, clean the sensing element of the MAF(there is a cleaner on the market, specific for this,,,,,just two screws holding it in)....when all is back together, and at normal operating temp, lightly tap the MAF or grab the harness into it and give it a wiggle...if the car reacts, then you might need one...

Thanks, If I need to replace the MAF or IAC etc - what brand? AutoZone - Orielly etc have a few brands. Stick with oem ones like AC Delco - Delphi etc?

It run rough this morning but not as bad so I'll find the TB gasket & MAF sensor cleaner. Wish I knew the exact cleaner name, some stores have no idea.

Always seemed to run into problems when using after market MAF's, rather than OEM, which are more expensive......

Stores never heard of this?

https://encrypted-tbn1.gstatic.com/shopping?q=tbn:ANd9GcRrGlttoirXrSA-mAQ_PHxeV58S4kqxDbF5gfsI_--4EzSq7owYHC9MzL11AhUNSKcuimycOw&usqp=CAY

I hurt my back (not working on car) and paid to have it done. But I wanted to say thanks again. I was going to clean the TB & check maf as described. That was the problem & the maf was defective. It runs real smooth & burns very clean.
So thanks again, wanted to say thanks for your advice.

Thanks for responding with the fix.....we appreciate it...good luck with your back....mine acts up once in awhile....