Smoking From Amf

[kcpth]

Hey everyone. I have a big problem and I'm pretty sure I am justified for the concern too. :o

I have a 92LS400 and today i went to start up my car. It usually takes 2 cranks before the cars fully starts up. It's been like this for quite sometime. Anyhoo.... by the 2nd crank I notice some smoke coming out of the engine area and it wouldn't start :o . So i popped the hood and notice the smoke was coming from the air filter area. So i took it apart and it seems like the smoke was coming through from the AMF (Air Mass Flow). I'm not 100% sure if that is the point of origin since most of the smoke has been aired out by the time I took apart the filter compartment but it seems like it. I didn't diassemble the part that connects from the AMF to the Engine. I only took the filter and the filter compartment off.

I didn't want to try and crank it again and cause further problems. Does anyone know what happened :cries: ?

Some history of the past few days: Well on Tuesday of Last week was the last time i drove it. My fuel tank that day was pretty darn close to empty by then... but was too tired to stop by a gas station since I was out the whole day. I tried to start it later on in the week like on Friday or Saturday... but it wouldn't start. I figured it was probably due to my house and driveway being on a hill (and pretty steep driveway) so possibly all the gas might have gone to the back of the tank. So today I filled up about 2 Gallons of gas in it and hence the problem came out. I checked the dipstick.... engine oil is not a problem.... all fluids seem to check out. However, I didn't check power steering fluid... but i dont think that would b the cause of the problem... engine should start up still... then smoke.

Thanks for the help. Any suggestions would be gladly appreciated.

Tom

[akewlguy]

umm..

What color smoke? How many miles?

Do you let it get low often?

Sounds like a cloged fuel filter. I am not an expert, but sometimes when you really look at an engine running when something is wrong you see minor things. I am not saying this smoke is not a big deal since I did not see it.

[kcpth]

well i usually fill up when the light comes on. This time i went a lil past that.... but i dont think it was terribly low. Well in terms of smoke.... hmmmm.... well it was greyish... or whitish.... but nothing like dark.

If it is a clogged fuel filter.... would it come out through that direction? I opened the Oil Cap.... i didn't see smoke coming out from there.... but then again.... like i said before... the smoke was slowly dying out... but there should be some built up smoke being released if i opened it from there. Well.... perhaps i will try starting the car again tomorrow.

Oh.... and the car has around 180,000 miles on it.... i haven't driven it as much this year.... since my girlfriend bought her ES300 and the rise of the gas prices. But i do make sure to start the car at least every few days and driving it around the block.

The engine doesn't seem to have any problems last i remember. The only problem i had with the engine happened like 2 yrs ago? Or maybe it was early last year. But there would be hesitations and jerking back and forth. I put like 2 treatments of Chevron with Techron.... and that cleared that problem right up. But that problem was probably due to me working and giving my car a 6 months rest without starting it once.... and thats when i learned that was bad. Only problem is i have NO AC and the !Removed! temperature gauge would rise from normal temp to EXTREMELY HOT and back down.... with no signs of overheating. I doubt that has anything to do with the AMF smoking though.... but im no expert either.

Thanks for the response kewlguy

[ko90ls]

wow terrible story, but you'll get thru!

dunno it sounds like the engne might've backfired or something? i'd check the owners manual for info about parking on inclines

[TexasLexus94]

Since you seem to have a habit of burning fuel down to the last ounce, it would seem possible that the throttle body which connects to your MAF sensor is crapped up with carbon. Since you know how to remove the MAF, you should get some carb cleaner and a stick and a toothbrush, and clean the throttle body and plate. Remember to clean the throat out with a rag, too. Also, after cleaning the throttle body, spray a little starter fluid down the throat, and start the engine. If it doesn't start, then it's something else. Best of luck.

[kcpth]

Thanks for the best wishes KO90LS

N yes... TexasLexus94.... i do have that problem of trying to do what Kramer did in Seinfeld on wondering how far past the E i can go :whistles: . I will give that a try this weekend... hopefully i wont have to work and hopefully it wont rain. If you think its a throttle body being carbed up.... do you suppose if i started the engine again... would it cause a problem?

I'll have to check if the engine is backfiring too. I'll search more on the forums on info on that. Thanks for all the tips and hints and ideas. I'll try to get everything out of the way.

Tom

[sha4000]

it sounds more like a short circuit to me if it happened as soon as you started up a clogged fuel filter will not cause the engine to smoke upon starup and neither will the maf sensor. either you have a wire touching ground somewhere near the smoke or your engine is overheating. just a guess though

[TexasLexus94]

Actually, kcpth, I drove the LS with the MAF removed, and it ran like a racehorse. Much better, but not recommended. But it's OK to see if the engine will start with the MAF removed. Remember that 60% of all problems occur upon startup (I read that somewhere), so your best bet is to see if you can get it running at all. Sounds like a crapped up ignition to me. Good luck.

[kcpth]

Yea it seems like I have a lot of work cut out for me if I want to try to solve this problem out without going to a mechanic. After I read Lexls's tutorial about how to clean the throttlebody.... i realized that its going to take a lot of time. I dont know if i'm willing to drain the coolant yet as i'm still a beginner DIYer. It seems simple enough, but knowing my own luck.... i'd probably break the bolt or something going wrong. So i will leave that part out for now. Let me take the whole Flow System apart and just take a look to see if anything is in there. I must admit... the filter is somewhat dirty.... but it should have started up.... and not have smoke billowing out of it. If anything... it would rob my gas mileage.

Well... i'll give you further details in the days to come. Thanks again for responding to my SOS.

[TexasLexus94]

I never do anything except remove the MAF stuff, and clean the throat. No coolant or anything like that. Please try everything before you're forced to take the car to the Lexus stealer-I even bought a backup car for this reason. So I have time to address the problems-Lexus = High costs. Mine has about 110,000 miles, but I still worry.

[bartkat]

Sounds like when you tried to start the car on the incline, it got starved for fuel and maybe ingested a little dirt and stuff. I'd start it up, smoke or not, and let it run awhile go get some good gas back in the motor.

[SKperformance]

This is definatly one of the worst recommendations to help fix a car thread.

1. there is no conclusive evidence that a fuel filter is anywhere near a problem to think it is one now all of a sudden. Every car i own i dry the tank, i have never had to change a fuel filter once i buy a car and do not buy from any gas station that does not have automated pumps which would mean dated rusty holding tanks would be in use.

2.MAF sensors don't get carboned they get dirty.Again what can this part do to make a maf show smoke?

You say smoke, now what did it smell like?

Gas or burnt material?

To me this is the only place to start in diagnoising a problem.

If you start any car cold and shut it off and look in the intake you will ALWAYS see a swirl of mist which is unburnt gas . All gas at cold have a high cranking injection duration. So once an engine is shut off the valves open will cause the left overs to drift up.

Without getting details giving people a best guess based on nothing is not going to help anyone.

I agree with Bart ,start the car !

[bartkat]

This is definatly one of the worst recommendations to help fix a car thread.

1. there is no conclusive evidence that a fuel filter is anywhere near a problem to think it is one now all of a sudden. Every car i own i dry the tank, i have never had to change a fuel filter once i buy a car and do not buy from any gas station that does not have automated pumps which would mean dated rusty holding tanks would be in use.

2.MAF sensors don't get carboned they get dirty.Again what can this part do to make a maf show smoke?

You say smoke, now what did it smell like?

Gas or burnt material?

To me this is the only place to start in diagnoising a problem.

If you start any car cold and shut it off and look in the intake you will ALWAYS see a swirl of mist which is unburnt gas . All gas at cold have a high cranking injection  duration. So once an engine is shut off the valves open will cause the left overs to drift up.

Without getting details giving people a best guess based on nothing is not going to help anyone.

I agree with Bart ,start the car !

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[sha4000]

it sounds more like a short circuit to me if it happened as soon as you started up a clogged fuel filter will not cause the engine to smoke upon starup and neither will the maf sensor. either you have a wire touching ground somewhere near the smoke or your engine is overheating. just a guess though

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ok maybe i shouldnt have said guess, but thats all anyone can do without physically seeing the car and running some checks. most advice you can get on a forum is an educated guess due to someone elses experience. anyway your right sk start the car after you have popped the hood and look in the engine compartment and see if it start to smoke again. smoke like that under the hood usually means something is burning and more than likely in my experience it can be a wire that is shorted to ground somewhere near the smoke since there is so much electrical stuff in there. is there any leaking fluids near the smoke. make sure to look at the engine compartment very carefully b4 you even start the car. with a problem like that it should be pretty evident. is your check engine light on?check all this out and get back to us.

[nc211]

maybe a little power steering fluid dripped on the alternator while it sat for that length of time??? A little electrical charge hit the fluid and burned it off? I hear it's not that uncommon of a problem on the 1st generation models. Of course, to be honest, on a 13 year old car, nothing is that uncommon anymore. Hoses crack, seals leak.

[ko90ls]

trust me, if you do clean the throttle body, the hardest part is draining the coolant! and the only drain necessary is the front drain !Removed!(personal expirence) very easy and straight forward. just use lexls' tutorial! the best way to check for possible leaking fluids is to park on the drive, check the engine and make sure everything is dry. wait the same amount of time and check for dampness in certain areas. if something is leaking you'd see areas that yould be a darker color, but if something is leaking would it burn on startup?

p.s. just trying to stay positive! good luck

[kcpth]

just to give u guys an update. I started my car like what some of you guys suggested... and... ITS ALIVE... it's really alive!! It started right up the next day.... n i drove it around.... n kinda gave it a good rev on the highway hopeing to blow off some carbon build up or dirt build up where it was. But i still plan to do a throttle body clean one of these days.... whenever my dad gives me a day off.

Thanks for all the suggestion guys.

Tom

[SKperformance]

Glad to hear.

[akewlguy]

Nice..

About the fuel filter.. I was just stating it could have issues if you run it low often.

Good luck..