mapavato

Hey guys,

recently replaced the galve cover gasket on my 99 RX300. After changing, I noticed that it started rough idling and won’t shift to 4th.

i had issues with my VVT solenoids in the pst so I thought it was time to replace them. I replaced both but the problem still persists.

if I reset the battery, it shifts to 4th but still rough idles. After a few minutes, it would stop shifting to 4th.

anyone familiar with this issue?

thanks everyone!

LeX2K

You need a code reader, check the code(s) and report back.

salimshah

We also expect check engine light to be ON and maybe the the trac light as well. If the check engine light is not one, please verify that it turns on when you move your ignition key from ACC to Run (one position before start) -- more details on self check are in the owner's manual.

Salim

mapavato

Here are the codes that came up:

P0300 - Random/multiple cylinder misfire
P0304 - cylinder 4 misfire
P0305 - cylinder 5 misfire
P0306 - cylinder 6 misfire
P0171 - System too lean (Bank 1)
P0136 - O2 Sensor Circuit (Bank 1 Sensor 2)
P0141 - O2 Sensor Heater Circuit (Bank 1 Sensor 2)

I'm not too concerned about the O2 sensor to be honest.

salimshah

Recheck all sensors wires etc related to bak 2 ,,,, the radiator side of the engine.

Salim

LeX2K

Oil control valves and screen #1 suspects.

mapavato

I cleared the codes then I checked the sensor wires on the three coils on the radiator side of the engine. All three seem to be working and plugged in.

I drove it for a few minutes and its rough idling as mush as before. It has a slow acceleration as if its struggling at first and then it would gain traction. It also seems to be shifting to 4th but is still rough idling.

Check engine light was on and I got the following codes:

P1305
P1315
P1325
P0305
P0171
P0141

mapavato

I just replaced both of them a few weeks ago but the problem still persists.

mapavato

My mistake. I forgot to clear the codes.

I cleared it and it seems to be working fine right now. Check engine light didn't come back on. Still rough idling though.

Could reconnecting cables have done the trick here?

salimshah

If you are getting rough idle I suspect the problem may still be there. You can connect at try to read and see if you have any pending codes.

Also check if your idle speed is low. Warmed up engine should be 750rpm. Check your vacuum hoses once again. The one behind the air filter box is typically out of sight.

Salim

mapavato

This is essentially what is happening right now: https://www.youtube.com/watch?v=Vcw8...ature=youtu.be

I have it on D with the brakes engaged.

salimshah

I see CEL lit. Please re read the codes.
Also please revisit all vacuum line connections. Specially the ones that you disconnected and reconnected.

Salim

mapavato

I cleaned the IACV with Carb Cleaner. Didn't really help and the problem is still there.

Vacuum connections seem to be okay as well.

Only one code came up P0305.

salimshah

Seems like a very relevant code ... cylinder 5 misfire. That is a bit hard to access ... nearest to the driver on the firewall side.

Best thing to do is swap the coil with #2 and later if needed swap the spark plug. See is the problem moves from #5 to #2. If you do sequential change you should be able to pin point if it is the coil or spark plug. If the problem stays after the swap .. you will have to trace back the primary side of the ignition wire ... it can be pinched etc.

Salim

mapavato

I swapped the #5 and #2. I went for a drive and there was no issue at all. Rough idle was gone, acceleration was good, shifts to 4th and no check engine light after the drive lasting about 10mins. I checked the codes and the only one was for the O2 sensor.

Could this be just have been a bad connection on the coil?