CaveCreek

Almost two years ago, my RX began to run rough and the CEL came on. I read code P1325, the dreaded IC #6. After reading the CL DIY, I bought six new NGK IFR6T11 spark plugs and three new BWD E789 ignition coils. I started to tackle the job, but got stuck trying to get the throttle body off. I had the RX parked in my extra garage, and put off the repair. I just tried to complete the repair (yes...two years later). I was able to get all three rear plugs and coils installed. I bolted the throttle body back on, and reinstalled the CC cable assembly and PCV valve hose. I changed the oil, but the other fluids all looked okay. Put in a new battery, K&N air filter, a gas additive and prayed.

Tried starting the RX and it would not start. The starter is turning the engine over, but the engine will not fire off. It is now giving me code P1760. After trying to start, it also gives all six ignition coil codes (P1300-1325), but those codes will clear. I got code P0768 from the history, but it also cleared.

The vehicle had a full tank of gas when the problem happened. Do you think it's the gas causing the start problems? Any suggestions?

99rx

iTrader: (6)

Sounds like you should attempt to siphon out all the old gas, put fresh 93 octane in and make sure all your connections are on correctly.

salimshah

If you still have a nearly full tank, you will need to store about 15gallons of gas.

You can just put in 2gallons of fresh gas once the tank is empty.

Stale gas is only one possibility. Have you tried pumping the gas pedal a few times and holding the pedal 3/4 down and cranking the engine.

Also clear all codes (or disconnect the battery for about 10 minutes) and then try to start. After then try reading the codes.


I have not tried it and I am not sure if is safe to introduce quick start fluid through the air intake. Maybe some one who has had some experience (both positive and negative) can share.


Salim

salimshah

one more ..

You may need couple of long cranks with gas pedal pumps. [make sure your battery is good]

Make sure you give couple of minutes to cool down the starter and the battery, between long cranks.

For all its problems, the carb equipped engines allowed more options to make the engine catch.

Salim

CaveCreek

Well...epic fail on the attempt to siphon gas from the tank. I believe there is a "ball valve" at the bottom of the fill tube which prevents the rubber tube from submerging in the gasoline.

Besides taking out the rear seat and accessing the fuel tank from the top, does anyone have any ideas on getting past the "ball valve" to do a simple siphon operation?

code58

My personal feeling is that bad gas from setting is not high on my probability list. I know a lot of people don't think gas will last the afternoon, so you'd better drive the tank empty on your lunch hour (obviously not serious) but my own personal experience has not been that. I live in So. Cal, and use 10% ethanol fuel (not really by choice). We owned a Class A motorhome (now sold) that sat for over 5&1/2 years. Tank was always kept full (when last used-Arco gas) and when I sold it the Arco-ethanol fuel had rotted the inlet rubber hose and soffened the 1 inch hose between fuel pump and outlet tube so that it was useless. Once the mechanics had dropped the tank partway to gain access to the pump (drained over 30 gal. into a new heavy duty trash can) and discovered the swollen mushy pump hose and replaced it and the pump (nothing actually wrong with pump) it fired immediately and ran like new. The fuel taken out was absolutely clear and not a trace of water or contamination in it or the bottom of the tank. I watched all of this take place on my RV pad. I probably wouldn't have believed it if I hadn't seen it with my own eyes. From the ethanol rotting the bottom of the inlet hose the tank had probably lost about 7-8 gal. of fuel over the years and still showed no adverse affects from the air exposure. True story, make up your own mind.
(BTW, they put the 30+ gal. back in the tank and drove away with it. Ran beautiful as always)

CaveCreek

Thanks for your experience, code 58. I will start looking at fuel lines.

Does anyone know about hearing the fuel pump when you turn the ignition to ON? Tried starting it again this morning and hear two clicks from the engine compartment when I turn the key to ON.

Also looking for the easiest way to remove fuel from the vehicle since siphoning will not work.

salimshah

Please dont grasp for straws, someone elses problem may not be yours.

You have to systematically confirm and or exclude things one by one.

If you can crank, then at least battery,starter are eliminated.

With WOT (full throttle) smell the exhaust ... to see if unburnt gasoline is making it there. IN long term storage, some time rodents nest in the exhaust blocking it .. so see if the exhaust is free.

To check the delivery of the fuel, disconnect the quick coupler [body to engine] fuel line. See my notes on knock sensor DIY. Exercise due care as fuel can stream out.

Check the presence of spark.

Timing is hard to gauge, but after storage the only thing bad could happen is a broke belt or crank position sensor.

Salim

CaveCreek

Salim,

Thanks so much for your time. I removed the front right ignition coil, attached one of the plugs I replaced earlier, and had my wife turn the ignition to START. Starter turned the engine, but I saw no spark. Shouldn't I be getting spark?

I also noticed a slight humming-type noise with the key turned to ON. Is that sound possibly the fuel being fed to the injectors? It seemed to be from the front of the engine block.

I will follow your additional suggestions and also check every ignition fuse and relay next.

salimshah

Forget about other things and trace why there is no spark.

Make sure you imobilizer is not acting up. Try another key and remove all magnetic things away (other keys).

See if the timing belt is turning. [Can some one post how to inspect it with minimum tear-up]

Check cam-shaft position sensor. Resistance cold 835-1400ohms and hot 1060-1645ohm

Check the crank-shaft position sensor. Resistance cold 1630-2740ohms and hot 2065-3225ohms)

Salim

CaveCreek

Okay Salim...exhaust is clear, but I can't really smell any gas fumes. All the ignition/starter/ECU fuses are good. I assume I checked for spark correctly by extracting the IC, inserting a spark plug, and watching for spark when the engine start was attempted.

Without a photo, I was unable to find the fuel line quick coupler. I have everything put back together, so if it is under the air filter box or throttle body, then I would have to disassemble those again.

I did read about the engine immobilizer and I did the masterkey/remote key thing (put each in the driver door then the ignition). Got some strange beeps, so I hope that didn't screw anything up. Any other advice to ensure the immobilizer is not the problem? Would that allow the starter to engage, but not provide ignition?

salimshah

Your post #9 states "no spark", so forget about other things.

Auto-security, [imobilizer] kills the ignition, and you can crank all you like.

Follow my previous post.

Beyond that, it gets out of league of a DIYer. If it is imobilizer, you may need to go to Lexus.

Salim

[PS: the quick link disconnect is way below the brake booster (master-cylinder .]

CaveCreek

Where is the brake booster?

I checked for spark again. Anyone please correct me if I did this wrong. I removed one of the front ignition coils, inserted a spark plug, and placed the spark plug threads against the engine block. When the engine was turned over, there was no spark at all. Should I buy a spark plug tester or was my method okay?

The engine immobilizer symptoms are identical to what I have -- engine turns over but will not start. However, when I placed the master key in the ignition, the security system light went out and stayed out. I did the same check with the other master key and the sub key. None of the keys would start the car, but they all made the security light go out.

Unless I am reading wrong, this means the immobilizer is not the problem and the ECU is receiving a valid transponder code. Looking for additional ideas to troubleshoot for no spark -- 2000 RX300. I will attempt to check the timing belt, cam shaft and crank shaft position sensors tomorrow.

salimshah

Ref to how to trace ignition ... [keep in mind there are two sources of ignition kill
1. Imobilizer
2. Ignition switch off.

http://easyautodiagnostics.com/ignit...l_theory_1.php

Once again stop chasing other things like fuel till you get a spark going.

Salim

code58

You SHOULD have had spark under those conditions, so long as there is good contact between the spark plug threads (ground) and the engine block. You live in AZ. and believe me there are desert varmits that love to chew on wires and other rubbere/plastic anywhere on the car, and even if it is stored inside, they are very ingenious about getting in. My brother lives in Mesa and has been victim of the desert varmits. They can chew in places it's hard to see (out of view areas).