No Power, Glowing Red Cats, Misfire, At Wits End.

[Blake_batonrouge]

Guys and gals, I am at my wits end with my Lex. I have a '91 LS 400. I am getting a severe misfire. I am idling at 500rpm and when I throttle the car up, it seems to stumble then also. I am smelling raw gas out the exhaust and it takes putting the accelerator to the floor to climb the slight incline into my driveway. I just changed the wires and put all new Denso Iridium plugs in. NO change, still running terrible. Any suggestions before I have this thing towed to the dealer. note: I have new rotors and distributor caps, but have not installed those as of yet.

[Alexander the o.k.]

Have you pulled the codes?

Do that 1st.

Also, check the trunk hinge wire harness.

[Blake_batonrouge]

Have you pulled the codes?

Do that 1st.

Also, check the trunk hinge wire harness.

I am getting no codes. The check engine light has not come on (it does work). Also, for a moment I had the brake failure light come on and has not come back on since. I looked at the trunk wiring where it sits in that black holder and all the wires were fine. Do I need to pull the black strip off of the "U" section of the actual trunk hinge?

[Blayd]

That stuff seems to hapen to almost everyones older LS400 including mine. As soon as mine gets out of the shop, for the same problems you just described, Ill let you know what the problem was.

[Randy&Bonnie]

..

[Blake_batonrouge]

Guys and gals, I am at my wits end with my Lex. I have a '91 LS 400. I am getting a severe misfire. I am idling at 500rpm and when I throttle the car up, it seems to stumble then also. I am smelling raw gas out the exhaust and it takes putting the accelerator to the floor to climb the slight incline into my driveway. I just changed the wires and put all new Denso Iridium plugs in. NO change, still running terrible. Any suggestions before I have this thing towed to the dealer. note: I have new rotors and distributor caps, but have not installed those as of yet.

Gee, still haven't gotten it fixed??

Quote "Thanks N.C.O. talked the guy down to $3500 and bought the car. Went to Lexus got a new coil pack and changed it out. Car is running fine now with NO misfire or glowing pass side cat. " Unquote.

http://us.lexusownersclub.com/forums/index...c=50855&hl=

It has reappeared!!!! Due to Gustav the dealer is not open and I need a car.

[smooth1]

It actually sounds more like a the fuel injectors. Have you pulled them and looked at em?

[Blake_batonrouge]

Injectors would make it do that? This problem just appeared suddenly. Also, I do not have a gas cap could this have anything to do with this?

[smooth1]

If your injectors are stuck open or are improperley delivering the fuel, then yes, as the fuel floods the flame kernal, you would experience the car misfiring and bucking some, then as the fuel is pushed out the exhaust valves and into the hot header where it gasses and burns there causing the cats to over heat. When you pull the spark plug it will have a moist black coating on it. Most techs automatically jump to the coils thinking that the spark plug is not firing. Which is correct, the spark plug is fouled out and not firring, but a bad fuel injector can also be overwhelming the spark and causing the misfire from too much fuel being delivered to the cylinder. You said you smelled a strong fuel smell also? Everything so far points tothe fuel injectors.

And, you should really have a gas cap on there. It does alot more than just devide the outside from the inside.

[smooth1]

I just reread you original post:

note: I have new rotors and distributor caps, but have not installed those as of yet.

And it's a 91?

Yeah, it could be that as well. If the spark plugs aren't firing, then gas is being pushed into the exhaust and causing the rest of the issues your expereincing. I originally read this as you just had them replaced, not have them but not installed yet.

[Blake_batonrouge]

I just reread you original post:

note: I have new rotors and distributor caps, but have not installed those as of yet.

And it's a 91?

Yeah, it could be that as well. If the spark plugs aren't firing, then gas is being pushed into the exhaust and causing the rest of the issues your expereincing. I originally read this as you just had them replaced, not have them but not installed yet.

Correct I have not put in the new rotors and distributors because you have to take the radiator and fan out to get them in and I didn't have time with the storm approaching.

[Blake_batonrouge]

Just wanted to give everyone an update and solution to my problem. It turned out the coil pack on the driver's side went out. I thought they had changed both packs, but it turned out they only replaced the one on top of the engine. Changed pack and again things are back to normal.

[IanRShearer]

Just wanted to give everyone an update and solution to my problem. It turned out the coil pack on the driver's side went out. I thought they had changed both packs, but it turned out they only replaced the one on top of the engine. Changed pack and again things are back to normal.

Hi there, apologies for re-opening an old thread, but my car, which I have only had for 2 weeks now has exactly the same symptoms, no power, both cats red hot, strong fuel smell. Can I confirm that one faulty coil caused both cats to glow hot?

I'm very relieved to find someone who had the same symtoms, wonderfull forum. I'm gutted my "new" car is off the road!

[17LexusOwner]

You could also try your O2 sensors, but I think if those were bad they would trip your Chk Light.

The symptoms seem similar to what happens when O2 sensors are bad though.

[IanRShearer]

You could also try your O2 sensors, but I think if those were bad they would trip your Chk Light.

The symptoms seem similar to what happens when O2 sensors are bad though.

Hi,

Thanks for responding. I do have codes 21 and 28, for both O2 sensors, but I always have them, I think its down to the LPG conversion, but I need to check this with the converter company.

Anyway, the codes were there before this problem suddenly appeared, I think I probably have no spark from one of the HT coil packs, but I haven't had time to check that yet. I hope that's the problem , comparitively easy to fix

[93ls400walt]

If it is one of the coils it is typically the one down low on the drivers side ( US model )

[IanRShearer]

If it is one of the coils it is typically the one down low on the drivers side ( US model )

I haven't had a lot of time to investigate yet, a quick look showed that the "top" coil HT side had 11K resistance to earth, which is OK, but I unpluged the HT cable and the car still started and ran much the same, so that would sugest its not OK

I will have to do some dismantling to get to the driver's side coil (It's not actually my drivers side, but I'm the visitor here)

Cheers

[chubyball]

Guys and gals, I am at my wits end with my Lex. I have a '91 LS 400. I am getting a severe misfire. I am idling at 500rpm and when I throttle the car up, it seems to stumble then also. I am smelling raw gas out the exhaust and it takes putting the accelerator to the floor to climb the slight incline into my driveway. I just changed the wires and put all new Denso Iridium plugs in. NO change, still running terrible. Any suggestions before I have this thing towed to the dealer. note: I have new rotors and distributor caps, but have not installed those as of yet.

Blake,

Did you replace the distributor by yourself?