Bobk528

This morning while I was driving on the expressway, the "Check Engine" icon started flashing and the engine was running really rough. Before I knew about the Lexus Forum, I would have gone into panic mode.

Instead, I turned the 2000 RX300 (88,300 miles on it) around, headed home and connected my diagnostic code reader, which displayed P0302. I then went to the Lexus Forum and performed a search, which seem to isolate the problem to a bad ignition coil in Cylinder no. 2. Lexmex had some good information. Since I live in a major city where the Toyota dealership is open seven days a week, I wrote down the part number listed in the forum and purchased Toyota part number 90080-19016 for $108.

After I got home, I was able to replace the coil in less than 8 minutes and erased the code, which eliminated the "Check Engine" light.

It runs great now but since the other coils and spark plugs are original, should I consider replacing all the other coils when I replace the plugs at say the 100k mile mark? I would normally not bother but since I am planning a long road trip this summer, should I replace as a preventive measure:

- 5 other ignition coils
- spark plugs
- water pump
- oxygen sensors
- any other parts that could leave me stranded in the middle of no where.

The RX has been trouble free but I do not want to take any chances while on the road.

salimshah

If you go down the list of possible things that can leave you stranded, you will be free towing another RX behind you.

These days I would say carry a flash-light, cellphone and check that the spare is inflated properly.

I would only suggest doing the recommended maintenance.

Salim

code58

It runs great now but since the other coils and spark plugs are original, should I consider replacing all the other coils when I replace the plugs at say the 100k mile mark? I would normally not bother but since I am planning a long road trip this summer, should I replace as a preventive measure:

I would say take your code reader with you so you are not totally clueless if you have a problem. The parts you are talking about are generally good for A LOT MORE miles than you have on your car. My bet is if you don't touch any of them you will come home without having pulled your code reader out. If you have a LOT of money and want a warm fuzzy feeling- go ahead and replace those things- but not because they are likely to fail on the road. One thing that is a good idea though, whether you replace the parts or not is to use dialectric grease on the coil to spark plug contacts and general area. Tends to eliminate arcing which will stress and potentially cause the coil to fail.

Salim is correct!

Lexmex

The coils don't go out that much. I had one go out on mine in Mexico and many remember that I used a modified Camry coil until I could get a true one for the RX300 down from the U.S. Coil is the one most likely (but really not that likely) to go out should you be on the road. Haven't seen an issue with the water pump nor spark plugs. Oxygen sensors won't leave you stranded but you will burn gas. You can at Toyota dealers get the Highlander V6 coil for the first generation Highlander. Thankfully, Toyota (and Lexus) dealers are way more common in the U.S. than they were in Mexico. Happy to be back.

thomas1

Dielectric grease is a thumbs up, it prevents moisture and corrosion to the electrical contacts between the plug and coil. Arcing can cause rapid coil failures.

Lexmex

Bad gas can cause coil failures. My uncle saw at least one every week. But I wouldn't expect this in the U.S.

JPAL

Hi everyone i need help with my 2000 lexus rx300 it started with a check engine light and i got a OBD2 scanner and got codes P1155 , P1135 so i replace O2 sensors (denso 245-9009) bank 1 sensor 1 and bank 2 sensor 1 then the CEL went away for 5 months and the CEL came on again and this time it was flashing then i have codes P0300 , P0301 , P0303 , P0305 , P0171 , P1150 , P1135 and P0125 . so now I don't where to start i oredered parts online NGK laser iradium spark plugs , set of ignition coils , radiator cap , coolant temp. sensor ,MAF sensor cleaner and timing belt kit. parts is arriving today i just want to ask if there's anything you guys can suggest what else i have to replace at this point i don't know whats going on with my car it already have 170k but ive been taking good care of it for 10 years.

sktn77a

iTrader: (2)

If you have a bad coil, you'll know about it (the engine will run real rough). If the engine is running fine, ignore the misfire codes for now as they can show up randomly with other fault codes.

Lexmus

JPAL, where did you buy the Denso A/F sensors? the correct part is 234-9009.

Given you are getting codes for all three rear cylinders misfiring, I doubt it is the spark plugs or coils. I know the oil control valve code for bank1 (rear) is normally P1349, but maybe that is the culprit. People have reported getting the misfire codes you report when the corresponding bank OCV is bad along with the A/F sensor code. However, I would first check the bank1 (rear) oil control valve filter and see if it is dirty. search the forums for instructions on how to remove it. It is next to the valve.

Parrokeete

No need to go overboard with preventive maintenance, just know that a used vehicle can have an issue at any time and try to plan ahead for emergencies.

salimshah

Interesting comment here ...

Do you have an alternate preventive maintenance schedule that you think should be followed instead of manufacturers recommendation. And is that based on personal experience or statistical based.

Salim