Jump to content


Low, Rough Idle, Extremely Slow Acceleration


wilsomy

Recommended Posts

1992 lexus ls400 has low, rough idle, extremely slow acceleration. car is giving cel code engine - 25, 26, trac code - 11, 51. wire loom w/ abt 20 wires, under passenger fender, touched, shorted. car would shut off when wires touched. reconnected all wire and car still has low, rough idle, extremely slow acceleration. please advise.

Link to comment
Share on other sites


1992 lexus ls400 has low, rough idle, extremely slow acceleration. car is giving cel code engine - 25, 26, trac code - 11, 51. wire loom w/ abt 20 wires, under passenger fender, touched, shorted. car would shut off when wires touched. reconnected all wire and car still has low, rough idle, extremely slow acceleration. please advise.

Sounds like EFI systems is running in limp mode, a failsafe condition when there is a problem in the system (to allow you to get to a service place or home). What changed recently? Did this just happen out of the blue or did it gradually get worse? Could be many things MAF, plugged fuel filter, low fuel pressure (pump or pressure regulator), or Throttle position sensor. Maybe ignition related but my guess is rule out fuel system first. You didn't just wash the engine did you? That could create ignition problems.

Frozen fuel line due to mooisture in fuel? Are you in cold area? If so thry some gas line antifreeze like HEET.

Link to comment
Share on other sites

1992 lexus ls400 has low, rough idle, extremely slow acceleration. car is giving cel code engine - 25, 26, trac code - 11, 51. wire loom w/ abt 20 wires, under passenger fender, touched, shorted. car would shut off when wires touched. reconnected all wire and car still has low, rough idle, extremely slow acceleration. please advise.

Sounds like EFI systems is running in limp mode, a failsafe condition when there is a problem in the system (to allow you to get to a service place or home). What changed recently? Did this just happen out of the blue or did it gradually get worse? Could be many things MAF, plugged fuel filter, low fuel pressure (pump or pressure regulator), or Throttle position sensor. Maybe ignition related but my guess is rule out fuel system first. You didn't just wash the engine did you? That could create ignition problems.

Frozen fuel line due to mooisture in fuel? Are you in cold area? If so thry some gas line antifreeze like HEET.

before the low, rough idle, extremely slow acceleration, problems occured. the car was running fine, the only problems was that i'd have to disconnect the battery because a vaccuuming or pumping sound constantly on was heard from the throttle body area, every time car was shut off. 3 weeks after the car has Low, Rough Idle, Extremely Slow Acceleration, loud in the muffler area. thats when i discovered wire loom w/ abt 20 wires, under passenger fender, touched, shorted. car would shut off when wires touched. reconnected the wires in the wire loom, weird sound coming from the throttle body area, after car was turned off stopped. But still having low rough idle and slow acceleration. pls adv

Link to comment
Share on other sites

If you have a "pumping/vacuum" sound in the throttle body area this could be the clue, check all the rubber hoses for the vacuum lines including the brake servo/booster pipe for damage or splits, if you cannot find any try spraying some "Easystart/ether/carb cleaner ( as known in the UK) around the throttle body and pipework whilst the engine is running to see if the engine picks up suggesting there is a leak in that area.

When you removed the battery lead did you move it away from the battery as the lead goes down close to the ignition coil and HT lead and the movement may have disturbed it.

Link to comment
Share on other sites

If you have a "pumping/vacuum" sound in the throttle body area this could be the clue, check all the rubber hoses for the vacuum lines including the brake servo/booster pipe for damage or splits, if you cannot find any try spraying some "Easystart/ether/carb cleaner ( as known in the UK) around the throttle body and pipework whilst the engine is running to see if the engine picks up suggesting there is a leak in that area.

When you removed the battery lead did you move it away from the battery as the lead goes down close to the ignition coil and HT lead and the movement may have disturbed it.

I'd be careful spraying ether on a hot engine or exhaust manifolds.

The flammablilty of liquids is measured by flash point this is the minimum temperature in which a spark will ignite it. Gasoline which is a mixture has a flash point of around 0 degrees C. One of the most flammable liquids, Diethyl ether has a flash point of -45 degrees so is
much more flammable than gasoline
.

Link to comment
Share on other sites

From what I've heard it could be an ignition coil. I have never had one fail but I believe the symptoms are similar to what you are discribing. Some one please correct me if I am wrong. FWIT even someone as careless as me wouldn't spray either all over a hot engine... or at least I hope.

Link to comment
Share on other sites

  • 1 month later...
i have replaced both ignition coils, rotorary buttons, spark plugs and wires. my catalytic converters are still glowing red. slow acceleration, low idle. what could be my other problems, pls adv

wilsomy,

If your cats are glowing red, and you have just changed both coils, plugs and wires, something is wrong with your ignition - you are burning gas outside your combustion chamber. The fuel is igniting in the exhaust/catalytic converter area. Recheck both coils and your plugs/wires, etc. Somewhere the spark is getting lost!

HTH

Mike

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



×
×
  • Create New...

Forums


News


Membership