beaudroix

History - I have owned this car for 10 years with no problems until two years ago. My wife reminded me today that our problems didnt begin until a local locksmith had to unlock our car to retrieve the key. I remember the locksmith had a tough time getting into the car but had mentioned the battery and security system.

Acceleration - you cannot accelarate over 2000 rpms, if so the engine bogs down, the check engine light comes on, I release the gas pedal for 5 seconds and the check engine light goes off and the engine runs smooth again.

Lights - the interior & dashboard lights work fine but when you turn the headlights on the interior & dashboard lights either go off completely or blink like a disco...

Please give me some feedback if you can diagnose any of these problems because five reputable mechanics cannot fix this...

steve2006

Hi,
You have the check engine light on so what codes have you got?
You also mention five mechanics have tried to fix the problems,what has been tried/replaced up to now?

ktranne

did any of the mechanics check for codes?

beaudroix

To Present Day - still drive the car everyday with not being able to accelerate over 2000 rpms and the crazy light situation...
04/28/10 - during an oil change they replaced driver side rear lower brake light again
09/09/10 - out of money and simply driving as is...
09/08/10 - a friend recommended paying the Toyota Dealership to inspect the whole car's wiring system for any problems. They did and could not find any shorts or any other problems.
08/17/09 - received ECU and paid the Toyota Dealership to reinstall. Service Mgr drove it for two days and still the same problem. Picked up car and Service Mgr had no recommendations...
08/03/09 - took car back to Toyota Dealership and the service mgr recommended replacing the ECU (main computer). He quoted a $2k for an OEM Lexus ECU, could not afford, so had the Toyota Dealership remove the ECU for me so I could send to a computer rebuilder located in Tennessee.
07/31/09 - p/u car from the Toyota Dealership and the car ran like brand new on the way home. Problem occured again the very next day...
07/28/09 - took car to Toyota Dealership and computer throwing codes for TPS & IAC Valve Sensors, followed service mgr's diagnosis to replace with OEM Lexus Parts
07/27/09 - car throwing code for TPS again, this time replaced with an OEM Toyota TPS supplied by O'Reillys
07/12/09 - car throwing code for IAC Valve, replaced IAC Valve
06/29/09 - car throwing code for TPS (throttle positioning sensor) and replaced TPS supplied by CarQuest
05/05/09 - replaced alternator
05/04/09 - replaced battery again
04/01/09 - replaced a/c compressor and drivers side rear lower brake light bulb
03/18/09 - replaced timing belt, hoses and gaskets
02/05/09 - replaced spark plugs, coils and battery
12/22/08 - replaced fuel filter and cleaned out throttle body
12/21/08 - engine begins stalling at 2000 rpms

beaudroix

someone asked earlier what happens if you "floor it". The "check engine light" comes on and the engine continually bogs down as long as you have your foot on the pedal. When you take your foot off the pedal, five seconds passes and "whalaa" the engine runs smooth again as long as the rpms dont get above 2000 rpms.

Should I remove the Mass Air Flow Sensor?

I saw a thread earlier where several folks had good results from this???

Extrudedco

If it's just the instrument cluster lights that are going out, it's likely one of the known electrical issues with the instrument cluster. You can dig it out and try to trace the exact failure point, or have it rebuilt.

As far as the bogging down goes, it could be an issue with the fuel pump or part of the circuit bypassing the fuel resistor for higher fuel pressure. If bypassing the resistor solves the problem, it's an issue with it switching to the higher voltage circuit, or the resistor is bad (not sure where the switching point is).

I can think of one instance I've seen on a forum where someone spent a long time chasing down a similar bit of bogging that turned out to be caused by sagging insulation under the hood blocking the intake.

Could possibly be a marginal sensor, but I'm not sure why that wouldn't throw a code.

deanshark

You can try unplugging the AFM to see if it changes. That is one of the symptoms of my car until I unplugged it. I get real bad fuel mileage though. Back in 7/09 they might have gotten the same codes for the TPS and IAC because they didn't clear the codes from the first time. Also, the "coolant temp sensor" does crazy things with the fuel system. Do a search on that and see what you come up with.

StevieA

can you take a camera with you and demonstrate while riding along what hapens when you floor it? DO from a standing stop and rollling along at speed - after it bogs, floor it again show us what happens

tonyfazt

if when you acccelarate from a stop to go and hit 2000 rpm its shrugs but then you easy off the gas and it keeps on going normally then

that my friend is the trac system kicking in happened to me

and NO pushing the trac off button will not fix it
but most likely one of the sensors that goes on the brake pads is torn or disconnected

phxls400

See if the powersteering line has a leak and leaking on your alternator.

Sounds crazy, but I had all kinds of issues when I discovered it. Once resolved, problem went away with the disco lights.