I’ve run 2 bottles of injector through 2 fuel cycles and hasn’t really changed much. I’ll definitely check the ground cable later
Have you tried doing an idle reset? May solve the problem.
2007 Camry, idling rough | Toyota Nation Forum
Tried it a couple times, never worked. I’ll try it again though
It was worth a try, several places I looked suggested it as a first measure,
On the STFT I’d assume you mean basically “bouncing” between 1.6 & 2.3. That’s well within bounds on the value, though I’d expect readings going from slightly negative to positive. If they’re always positive then it’s running a little lean. A steady LTFT is pretty normal. But the STFT should be bouncing.
You’ve never said anything about issues other than at idle. When you hit the gas and are rolling and under acceleration are there any issues?
At this point I’d do one of two things. The first is to just keep driving until the dumb thing finally throws a code. That at least gives you a place to start.
(Did this rough idle come on all of a sudden or more of a slow build up?)
The other is to just throw a new crank sensor on it. @Tester is a knowledgeable / long time mechanic and it was the first response. And as @Mustangman noted, they’re not expensive and generally not too hard to replace.
For example, when the light goes green and I floor it, it wouldn’t respond immediately it would take a second then the engine goes pretty quick im not sure how to explain it but kind of like when I put the pedal down to the floor it’ll take like 3 seconds then go up and start going. For the crankshaft engine on my car it seems pretty easy just need to pop off the passenger side wheel to gain access to it and it’s just a bolt and connector. I’ll change it soon when I get less busy
I’ve had rough idle issues that were the result of valve gaps (usually exhaust) out of adjustment. Over time the valves may recede in the head, making the gap smaller and smaller. That causes a misfire and usually sets a code.
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The rough idle goes away if just power brake a tad bit while stopped
Fuel trim is just the computer changing the fuel ratio for current conditions. Lean or rich depending. It should be constantly changing or you have a lazy O2. Hard to see how this could have much to do with a rough idle.
The reason I mentioned injection cleaner is b/c the only times I’ve had this symptom was on my carbureted truck, and that was caused by a clogged fuel port in the carb. Since injection cleaner didn’t help in your case, seems unlikely for your car. hmmmm … the problem is that there are many possible causes for this symptom, so what else ? … (presuming you’ve already tested the ideas above) …
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Maybe a battery voltage or alternator problem. The could explain why it is worse at low rpm. Before the first start of the day (car sits unused overnight) the battery should measure about 12.6 volts; then immediately after starting the engine, 13.5 - 15.5 volts. Easy test. Ask your shop to measure those voltages for you.
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Ask shop to measure the fuel-rail pressure.
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A prior poster was having a similar problem on his Corolla as I recall, and went down this same path. Replaced a lot of stuff, did a lot of tests. Eventually he took the car to a shop, who diagnosed it right away as being a problem with the valve timing. He replaced the timing belt, and that immediately solved all the symptoms. Your car probably uses a timing chain rather than a timing belt, but it could still have problems with the valve timing. Ask your shop to check that function. There may be a problem w/the VVT actuator for example.
I’m gonna check the ignition coils today, to check for anything abnormal, for the crankshaft pos sensor it’s in a tricky spot but honestly it very well could be the sensor. I say this because i notice some cracks in the wiring ( not the vehicle connector ) is there a way to check the sensor using a multimeter or something before replacing it?
I don’t understand that comment. If you’re stopped, isn’t your foot on the brake anyway?
It throws off the air/fuel mix, so it can give a rough idle.
Yes. I don’t know how it works on your car but those sensors are often just a coil of very small wire. When a magnet moves past, a voltage is induced into the wire. The failure mode however is often that the thin wire breaks intermittently when the sensor is in use and hot. When cold it tests ok. A problem w/the magnet that the sensor senses can cause this same problem. That part is often called the reluctor wheel. Inspect that part if you can see it for any apparent problems, like it is coated with gunk or a segment is chipped off & missing.
I mean like holding the brake and just tapping the gas pedal a little bit
There’s definitely gunk around that wire for sure
Gunk on the wire isn’t a problem usually. But gunk deposits on the reluctor wheel is.
Where can I find that?
which engine? 2az fe or 2az fxe? Look for emissions sticker under the hood.
Tester
The reluctor wheel for the crankshaft position sensor is inside the engine.
How long have you been battling this issue?
