Car Is Drinking Gas & Barely Accelerates

[Lexls]

Ok my car starts perfectly now but has developed an even worse problem. It barely accelerates now and it's seriously drinking gas. I can smell it too, it's an extremely rich fuel mix. It kind of sounds like something is blocking the path of the exhaust, it's got a low pitched rumble sound to it and lot's of white smoke comes out. I really hope you guys can help me figure this out.

The only thing I can think of is something burned out, maybe a fuse. When my battery was charged the guy that helped me flipped the 'boost' switch on his charger...maybe that did something. Tried checking the codes and nothing came up. Reset the ECU and that seemed to help, but then the problems came back.

I'm sooo confused unless I can figure this out soon I may have to bring it in, not much time.

[ArmyofOne]

Ok my car starts perfectly now but has developed an even worse problem.  It barely accelerates now and it's seriously drinking gas.  I can smell it too, it's an extremely rich fuel mix.  It kind of sounds like something is blocking the path of the exhaust, it's got a low pitched rumble sound to it and lot's of white smoke comes out.  I really hope you guys can help me figure this out.

The only thing I can think of is something burned out, maybe a fuse.  When my battery was charged the guy that helped me flipped the 'boost' switch on his charger...maybe that did something.  Tried checking the codes and nothing came up.  Reset the ECU and that seemed to help, but then the problems came back.

I'm sooo confused  unless I can figure this out soon I may have to bring it in, not much time.

←

clogged/plugged catalytic converter(s)...also could be a head gasket.

[silvermate]

man buddy you've been having some rough luck with your LS lately

i have to agree with Army,

the first thing i thought of when you mentioned those symptons were clogged Cat or Cats...........its gotta be that...........

we had the same problem on my brothers Tahoe, same symptions same everything, for the life of me i couldn't figure it out, we had to take it to the shop........... Diagnosis>>>Clogged Cat

so if you were ever going to do an exhaust upgrade nows the time

[Lexls]

Yeah man, it's been stuggling lately...good thing I work at home so this isn't the end of the world ;)

Well, it sounds like I'm gonna have to bring her in. My LS has always had a little too much smoke coming out of the exhaust. I guess the cats just died finally. Your diagnostic does make sense and I too feel like something is clogged. I'm gonna look into a shop around here. Thanks guys :)

[silvermate]

good luck buddy.

you actually might want to price some aftermarket cat back systems, it may be cheaper to go that route than OE. i'm not sure though. <_<

i do know that those cats cost a pretty penny

anywho, good luck to ya man, i'm sure you'll get her fixed in no time. :D

[SKperformance]

A dead cat will only maek you smell raw gas

a clogged cat will cuase a rough engine

so it is one or the other for those symptoms

Kind of don;t think it is a plugged cat.

Pretty sure you have a cap and rotor

change them first

[92Lex]

Maybe your timing belt skipped a tooth. I had the exact same symptoms when I did my timing belt...I pulled off the belt, realigned it and cussed the whole time. Not sure how slow your car accelerates but with mines, I floored it and it barely crawled. Is it driveable?

I doubt cats are clogged but you could try pulling them off to see if you regain power.

Caps and rotors is definitely what you should take a look at first.

[Lexls]

Hmm we have some saying plugged cats and other saying that's not so . I've been doing a lot of searching both here and on CL and have found several people with the same symptoms as mine and it turned out to be 1 or more cats.

How in the world could my timing belt jump a tooth! The car was perfect before my vactation, not used, and then developed this problem. My gas milage was getting progressively worse before vacation though....forgot about that.

If it's the caps and rotors would the cap be cracked?

Ohhh I also forgot to say this....the longer the car is on the more of a plastic-like funky burning smell develops, like something under the car is getting too hot (no fires or melting)....hard to describe the smell. Also, the car does get up to highway speed, it just takes a long time.

[blake918]

My LS had the exact same symptoms when I accidently filled up the spark plug cylinders(or whatever they're called!) with water while cleaning the engine.:chairshot: I had trouble getting to AutoZone for a code reading. She would hardly move in anything higher than second which made sense after they retireved 4 or 5 misfire codes, and the gas fumes were horrible.

[SKperformance]

if you are running rich you are going to overheat the cats which will cause them to smell and smoke

[ArmyofOne]

if you are running rich you are going to overheat the cats which will cause them to smell and smoke

←

they are clogged, make no mistake.

and a catback system wont help. LOL. its his cat thats clogged. where ar eyou located? ill talk to my guy and see what i can do about getting you one/two discounted...PM me.

also, check here:

www.newlexusparts.com

www.discounttoyotaparts.com

they are msot definately clogged. i would say you have what is known as the "china cat" syndrome, the car has been running rich for a long time, the material inside the catalytic converter (the honeycomb brick if you will) is breaking down. look at your tailpipes, do they have little pieces of charcaol looking stiff in them> thats definately what it is if so, but depedning on the system, these chunks dont make it all the way out, instead they sit, usually at a bend in the exhaust, and collect, until they clog the exhaust.

try starting the car, and unscrewing the oil cap. if you get excess pressure, thats probaby what it is. unscreing the oil cap really si the only way to releaive excess pressure inside the engine without creating a mess. it may slosh a little oil at you though. although i drove 10 miles with my cap off one time...didnt spil a drop.

whatever you do, avoind driving the car, if the cats are clogged, and you drive them that way, you can get backfiring if the pressure builds enough. and thats not good, ESPECIALLY on an engine with EFI.

a custom bent, true dual at an exhast shop could run you as little as $350, not including the mufflers and cats.

[92Lex]

How in the world could my timing belt jump a tooth!  The car was perfect before my vactation, not used, and then developed this problem.

←

It's been sitting there and was perfect before your vacation, but for you to be able to determine that there was a problem, you had to start the car right? A bad timing belt tensioner could lead to a timing belt skipping or tooth. I'm not saying that this is your situation but there's always that chance.

Hey Army, how are you SO sure his cats are gone? Even if he has what you call the "china cat" syndrome, don't you think it's important that he figures out why his car is running so rich that it overheated his cats? It would be a bttch to burn up new cats.

[jzz30]

coils? sounds like..

[Lexls]

I'm bringing it to the shop closest to my house. We'll see what the pros have to say, hopefully they can figure this out quickly. I'll keep you guys posted.

[ArmyofOne]

How in the world could my timing belt jump a tooth!  The car was perfect before my vactation, not used, and then developed this problem.

←

It's been sitting there and was perfect before your vacation, but for you to be able to determine that there was a problem, you had to start the car right? A bad timing belt tensioner could lead to a timing belt skipping or tooth. I'm not saying that this is your situation but there's always that chance.

Hey Army, how are you SO sure his cats are gone? Even if he has what you call the "china cat" syndrome, don't you think it's important that he figures out why his car is running so rich that it overheated his cats? It would be a bttch to burn up new cats.

←

i have seen this many many many many times, mor etimes than i have fingers and toes, and every time it was clogged cats.

[jzz30]

wager? :P :chairshot:

[Lexls]

wager? :P  :chairshot:

←

Hahaha, you still have time. I brought it in yesterday but they haven't looked at it yet.

[silvermate]

are you going to get her back today?

make sure you keep us posted. :D

[taildragger]

Ok my car starts perfectly now but has developed an even worse problem.  It barely accelerates now and it's seriously drinking gas.  I can smell it too, it's an extremely rich fuel mix.  It kind of sounds like something is blocking the path of the exhaust, it's got a low pitched rumble sound to it and lot's of white smoke comes out.  I really hope you guys can help me figure this out.

The only thing I can think of is something burned out, maybe a fuse.  When my battery was charged the guy that helped me flipped the 'boost' switch on his charger...maybe that did something.  Tried checking the codes and nothing came up.  Reset the ECU and that seemed to help, but then the problems came back.

I'm sooo confused  unless I can figure this out soon I may have to bring it in, not much time.

←

[taildragger]

oops

[taildragger]

It only cost me $625.00 to replace the three cats on my 1992 SC400.. Sure wish you had sent your problem in SOONER........I would have taken all this free advice and saved $$$$$$$$$$ as my car STILL runs the same.. cap & rotor NEXT!

[taildragger]

Take all this free advice..starting with the cap and rotor......sure wish I had gotten same..I spent $625.00 on installing all 3 cats on my 1992 SC400..IT still runs like yours...

[ArmyofOne]

Take all this free advice..starting with the cap and rotor......sure wish I had gotten same..I spent $625.00 on installing all 3 cats on my 1992 SC400..IT still runs like yours...

←

when the cats go, you cant just replace them, o2 sensors and other things have to be replaced too, usually.

as for the above issue, have you tried disconnecting the battery to let the ecu reset?

[Lexls]

Conclusion

Well, I just picked up my car and it runs smooth as ever now :D :D. Quiet, smooth, normal exhaust smell, power...it's all good, it runs like a Lexus again!

Diagnosis: LH ignition coil was totally dead. Also, a few vacuum lines were broken and one fitting was broken. I broke the fitting a while ago and ghetto rigged it to work.... The tech had to repair the vacuum lines and fitting first, then diagnosed the coil to be dead.

coils? sounds like..

←

Good job jzz30!

I took a quick look under the hood and the fitting is like new again, incredible! This was a tough problem and the guy that worked on my car was really good.

The total damage was $307....it would have been more but the guy that called me messed up with his estimate a bit so he took off some labor costs. Got a free car wash coupon too and my car is in desperate need of one, that's worth ten bucks. Anyway, I think this was a pretty good deal considering it was a tough problem to diagnose.

Once it warms up here and I can work on my car again I'll probably replace the RH coil just as a preventive measure. Caps and rotors have been on my to do list for a while and those will get done too, I already have those parts.

Thanks to all that helped with ideas, you guys are great, one of you was even right! B)

[ArmyofOne]

Conclusion

Well, I just picked up my car and it runs smooth as ever now  :D  :D.  Quiet, smooth, normal exhaust smell, power...it's all good, it runs like a Lexus again!

Diagnosis: LH ignition coil was totally dead.  Also, a few vacuum lines were broken and one fitting was broken.  I broke the fitting a while ago and ghetto rigged it to work....   The tech had to repair the vacuum lines and fitting first, then diagnosed the coil to be dead. 

coils? sounds like..

←

Good job jzz30!

I took a quick look under the hood and the fitting is like new again, incredible! This was a tough problem and the guy that worked on my car was really good.

The total damage was $307....it would have been more but the guy that called me messed up with his estimate a bit so he took off some labor costs. Got a free car wash coupon too and my car is in desperate need of one, that's worth ten bucks. Anyway, I think this was a pretty good deal considering it was a tough problem to diagnose.

Once it warms up here and I can work on my car again I'll probably replace the RH coil just as a preventive measure. Caps and rotors have been on my to do list for a while and those will get done too, I already have those parts.

Thanks to all that helped with ideas, you guys are great, one of you was even right! B)

←

ah, well, cant win em all... :D

however, i would liek to point out had you rove it very long/far with the coil out, it would have plugged at least 1 cat, maybe all. it was running wayy rich, since only 1 bank of cylinders was firing, the other 4 were totally dead, yet still getting fuel.

ok ok, you are right, im trying to justify my loss. LOL.

Glad you fixed it. and while logic would dictate that you would replace the other coil soon, i wouldnt unless it goes too. Coils are one of those things, they either work or not. so replacing it wont nessecarily help keep you out of trouble, if its working, my reccomendation is to leave it alone until it goes... Ignition systems are finicky creatures. everything has to be right, from the timing to the spark.