IS350 rough idle issue
#16
Intermediate
Any idea how difficult a throttle body cleaning would
be on the turbo engine? I imagine access may be harder
be on the turbo engine? I imagine access may be harder
#17
drives cars
While I don't have a ton of experience with the 2.0-liter turbo in the IS specifically, I can tell you that the one in the NX idles a little lower than that in my experience. More like 700-800 when it's warmed up. The 2.0 EA888 in my former GTI and now in my GLI will idle at 750 or so with A/C off, 800 with it on. So, slightly higher idle RPM than the ole 2GR but not significantly.
#18
Pit Crew
Thread Starter
I am confused about my engine oil level dip stick reading. One side is higher than the other. Does anyone know which side of the dip stick represent true engine oil level?
#19
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The pic on the right looks like it's a little pass the lower dot.
The pic on the left you can see the oil a little pass the first dot, but after that I can't really tell.
Because dipstick tubes are rarely straight, you will get this scraping effect on one side when you pull it out.
The way to tell which side is the correct reading is to look at the oi line. If it's a distinct line perpendicular to the dipstick, then that's the oil level. If the line is smudged, then that is not the correct reading.
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gamma113 (12-14-20)
#20
drives cars
It's either my bad eyes or my monitor, but the oil is so clean I can't see it on the dipstick lol! At least not the level.
The pic on the right looks like it's a little pass the lower dot.
The pic on the left you can see the oil a little pass the first dot, but after that I can't really tell.
Because dipstick tubes are rarely straight, you will get this scraping effect on one side when you pull it out.
The way to tell which side is the correct reading is to look at the oi line. If it's a distinct line perpendicular to the dipstick, then that's the oil level. If the line is smudged, then that is not the correct reading.
The pic on the right looks like it's a little pass the lower dot.
The pic on the left you can see the oil a little pass the first dot, but after that I can't really tell.
Because dipstick tubes are rarely straight, you will get this scraping effect on one side when you pull it out.
The way to tell which side is the correct reading is to look at the oi line. If it's a distinct line perpendicular to the dipstick, then that's the oil level. If the line is smudged, then that is not the correct reading.
#21
A 2015 IS250 idle speed is supposed to be 650-750RPM at operating temperature with AC off.
If you don't have a check engine light on, it may be a little tougher to figure out the issue.
Also, when you shift to Park, I would suggest giving the throttle a blip first to give it a chance to settle and see if it's still idling over 1000RPM.
In some cases there could be carbon buildup around the flap preventing it from closing properly, which could cause the idle to be higher.
If you don't have a check engine light on, it may be a little tougher to figure out the issue.
Also, when you shift to Park, I would suggest giving the throttle a blip first to give it a chance to settle and see if it's still idling over 1000RPM.
In some cases there could be carbon buildup around the flap preventing it from closing properly, which could cause the idle to be higher.
I have the 200T and sometimes my car idles at 1000-1100, after cold start while in park. It does drop down to 800-900 when the car is in drive. If I put the car back in park it will sometimes stay at the 800-900 range or sometimes go back up to 1k-1.1k.
You mentioned carbon build up for the 250 but is this something that can also be causing the inconsistent idle behavior of my 200T?
#22
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I have the 200T and sometimes my car idles at 1000-1100, after cold start while in park. It does drop down to 800-900 when the car is in drive. If I put the car back in park it will sometimes stay at the 800-900 range or sometimes go back up to 1k-1.1k.
You mentioned carbon build up for the 250 but is this something that can also be causing the inconsistent idle behavior of my 200T?
You mentioned carbon build up for the 250 but is this something that can also be causing the inconsistent idle behavior of my 200T?
Cold start idle can be anything it needs to be depending on how cold it is. Where I am in the dead of winter (January - February) it wouldn't uncommon to cold start and the car be idling at 2000RPM.
Accurate judgement of idle speed can only be done with the vehicle at operating temperature.
The fluctuations in idle speed between Park and Drive are normal as when the vehicle is in Park, there is no load, so the RPM's will tend to be slightly higher than when in Drive.
To shift to Drive you first need to step on the Brake pedal...this alone will change the idle speed slightly as you are taking vacuum from the engine by stepping on the brake pedal.
Then when you shift to Drive that also engages the tranny putting a load on the engine, causing the RPM to drop slightly.
As you have already noticed, once you put it back in Park, and release the pedal, the RPM will rise again...depending on how cold the engine still is, it may go up a little or a lot.
#23
A 2015 IS250 idle speed is supposed to be 650-750RPM at operating temperature with AC off.
If you don't have a check engine light on, it may be a little tougher to figure out the issue.
Also, when you shift to Park, I would suggest giving the throttle a blip first to give it a chance to settle and see if it's still idling over 1000RPM.
In some cases there could be carbon buildup around the flap preventing it from closing properly, which could cause the idle to be higher.
If you don't have a check engine light on, it may be a little tougher to figure out the issue.
Also, when you shift to Park, I would suggest giving the throttle a blip first to give it a chance to settle and see if it's still idling over 1000RPM.
In some cases there could be carbon buildup around the flap preventing it from closing properly, which could cause the idle to be higher.
#24
Pit Crew
Thread Starter
Update
My low idling issue came back. It hovers around 550 to 580 RPM without ac or light. As soon I turn on AC or light RPM goes up to 680 RPM. I wonder if it might be either:
-IAC?
-PVC valve? Do they cause low idling
-Drivr belt? Although it's only 70,000km
-Fuel injectors? I have cleaned with royal purple recently. With while to try again?
-Vaccum leak? Any obvious sign I could check?
-Spark plugs? although it's only 70,000km. Do they go bad that early?
My low idling issue came back. It hovers around 550 to 580 RPM without ac or light. As soon I turn on AC or light RPM goes up to 680 RPM. I wonder if it might be either:
-IAC?
-PVC valve? Do they cause low idling
-Drivr belt? Although it's only 70,000km
-Fuel injectors? I have cleaned with royal purple recently. With while to try again?
-Vaccum leak? Any obvious sign I could check?
-Spark plugs? although it's only 70,000km. Do they go bad that early?
#25
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Update
My low idling issue came back. It hovers around 550 to 580 RPM without ac or light. As soon I turn on AC or light RPM goes up to 680 RPM. I wonder if it might be either:
-IAC?
-PVC valve? Do they cause low idling
-Drivr belt? Although it's only 70,000km
-Fuel injectors? I have cleaned with royal purple recently. With while to try again?
-Vaccum leak? Any obvious sign I could check?
-Spark plugs? although it's only 70,000km. Do they go bad that early?
My low idling issue came back. It hovers around 550 to 580 RPM without ac or light. As soon I turn on AC or light RPM goes up to 680 RPM. I wonder if it might be either:
-IAC?
-PVC valve? Do they cause low idling
-Drivr belt? Although it's only 70,000km
-Fuel injectors? I have cleaned with royal purple recently. With while to try again?
-Vaccum leak? Any obvious sign I could check?
-Spark plugs? although it's only 70,000km. Do they go bad that early?
To address your list of suggestions:
- IAC - Vehicle is not equipped with one due to electronic throttle body
- PCV - More so the PCV hose could cause an idle issue if it is damaged/disconnected/leaking
- Drive belt - won't cause an idle issue
- Fuel injectors - Any part of the fuel system that has an issue could cause an idle problem - injectors, pump, regulator, etc. An "on car" fuel injector cleaning of the fuel injectors would be a good idea...will need equipment for that, or a shop
- Vacuum leak - A big leak should trigger a Check Engine light...a small leak may take some time to trigger a light. Basically anything attached to the intake, or the intake itself, could cause a vacuum leak. You could visually check all vacuum hoses and the air intake hose
- Spark plugs - Although the plugs have 70,000kms on them, they are also 8 years old...regardless if they fix the issue or not, changing them might not be a bad idea
#26
Pit Crew
Thread Starter
The IS350 idle speed with A/C and lights off should be 600-700RPM.
To address your list of suggestions:
To address your list of suggestions:
- IAC - Vehicle is not equipped with one due to electronic throttle body
- PCV - More so the PCV hose could cause an idle issue if it is damaged/disconnected/leaking
- Drive belt - won't cause an idle issue
- Fuel injectors - Any part of the fuel system that has an issue could cause an idle problem - injectors, pump, regulator, etc. An "on car" fuel injector cleaning of the fuel injectors would be a good idea...will need equipment for that, or a shop
- Vacuum leak - A big leak should trigger a Check Engine light...a small leak may take some time to trigger a light. Basically anything attached to the intake, or the intake itself, could cause a vacuum leak. You could visually check all vacuum hoses and the air intake hose
- Spark plugs - Although the plugs have 70,000kms on them, they are also 8 years old...regardless if they fix the issue or not, changing them might not be a bad idea
Should I consider changing engine oil and do another round of intake cleaning with fuel injector cleaner and intake cleaner?
Do I need to replace spark plug again? If so is it just once cylinder?
Does our car shut one cylinder's fuel injector if it doesn't ignition coil in plug in?
#28
Pit Crew
Thread Starter
I changed my spark plugs today. I accidentally forgot to plug back one of the ignition coil wire connector when starting the car. It cause misfires. I left it on for about 1 minutes in park before I turn it off. Misfire fully resolved after I plug it back in the ignition coil wire connector. I am worry petrol may go in to mix with engine oil.
Should I consider changing engine oil and do another round of intake cleaning with fuel injector cleaner and intake cleaner?
Do I need to replace spark plug again? If so is it just once cylinder?
Does our car shut one cylinder's fuel injector if it doesn't ignition coil in plug in?
Should I consider changing engine oil and do another round of intake cleaning with fuel injector cleaner and intake cleaner?
Do I need to replace spark plug again? If so is it just once cylinder?
Does our car shut one cylinder's fuel injector if it doesn't ignition coil in plug in?
i noticed tip of all my old spark plugs are red. See photos below. Is there anything I need to concern?
#29
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It's looking ok...obviously the plugs were in there a while, so they have the usual signs of wear and some carbon build up.
If the idle is resolved, then just keep on trucking...maybe change the plugs again at the same interval as this time...if you still have the car at that point.
If the idle is resolved, then just keep on trucking...maybe change the plugs again at the same interval as this time...if you still have the car at that point.
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