2006 LX470 180k ; After 150 miles of 70-80 mph driving,occasionally after exiting the freeway my LX will have a rough idle and stumble.After sitting for a few minutes(10-20) it fires up as nothing had happened and runs as it should.No codes stored,all gauges normal,highway driving no problem….I’m thinking sticking egr valve. Anyone else had this malfunction?
Sticking EGR ?
- Thread starter DBULL
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Have you pulled and inspected your coil packs?
May be worth a closer inspection
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- #7
I thought as rough as it was running that it would throw a code if it was a coil.Another thought is that I fueled in Chattanooga Tennessee which would have been a winter blend and drove to Atlanta and got caught in stop and go traffic when the first episode occurred. I coasted off the road,ran the codes and restarted.Stopped again in Tifton(130miles) car ran great,no problems,Stopped in Jacksonville Florida, no problems,Drove another 50 miles and stopped at a red light and the stumble/erratic idle was back.Continued to our rental house( 2 miles,) and this morning running as normal.Possibly a fuel issue with the differences in temperature?It almost feels like a vapor lock when it occurs..
Thanks for your input.Sadly all of my SnapOn tools are in Tennessee.
Thanks for your input.Sadly all of my SnapOn tools are in Tennessee.
Clean the throttle body and the MAF. Check the sparkplugs haven't loosened up. Shouldn't need anything else.
Fuel filter?
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- #10
I cleaned the maf and tb yesterday morning alongwith some sea foam in the tank.I’ve driven around a 100miles per day in stop and go traffic over the past couple of days without a hiccup.I purchase a NAPA Goldfuel filter(which I thought was made by WIX) before my trip but when I opened it there were made in China stickers in two places.I really don’t think it would be the fuel filter because once it gets past idle it runs great.
Coil packs can cause weird things sometimes. I had a weird hesitation when driving and thought the torque converter was going out. Never had a problem at idle. I was getting ready to replace the trans when someone reamended checking the coil packs for a misfire condition. I had NEVER had a CEL. I checked the coils and lo and behold one of them had a crack down the side of the coil. I looked down the spark plug tube and you could tell it had been arcing on the spark plug tube causing the misfire. I replaced it and everything has been good for a couple of years now. It never threw a CEL.
I had someone dump a Sequoia on a relative for $1000 because they swore it needed a new engine, wouldn't idle, backfired, etc. All I did was clean the MAF and TB and it ran perfectly. Sold for 8k. These engines have no idle air valve, it's all done by the electronic throttle body moving ever so slightly a couple hundred times per second. So even a tiny bit of crud or carbon build up can cause problems. The MAF also throws a fit when dirty, I've "fixed" a couple 4.7s now by just cleaning the MAF.
Diagnose it like any other engine. It needs fuel , air , spark , and compression.
Air - Remove and inspect air filter for debris in air box. Remove and clean maf sensor ( disconnect battery first )
Fuel - I suspect it's getting fuel but you may want to ask yourself when you last replaced the filter. Bad gas is a lot less likely now a days and it shouldn't cause the engine to spit and sputter unless its really nasty fuel.
Spark - Sounds like you are going to look into this but maybe its time to just do some plug / coil maintenance
Compression - I suspect the 2UZ is fine in that category unless you have been overheating and roasting it.
It may also pay to better define your symptoms. So what, you come off the freeway and the idle is just a little rough? Do the rpm's fluctuate or is it just a sound / vibration thing? Does it stall? You kind of just described a rough idle which then goes away which maybe isn't even cause for any concern.
2006 LX - 202k miles: I have been dealing with the exact same issue for the past 4 summers in Las Vegas, since I bought the vehicle. At least 2 - 5 times each summer, when the afternoon temps are nearing or above triple digits and I've been driving it around town and on the freeway (staying on the gas pedal), I will exit the freeway and come to a stop/idle and the engine will misfire and then stall. It doesn't happen every time, but it happens several times every summer, never at a good time or place.
I then have to sit on the side of the road for 10 - 30 minutes, in 100+ degree sun, after which it will start right up as if there was never a problem. I put in a new OEM fuel filter before last summer and that had zero impact on the issue. As soon as the summer hit, it misfired and stalled again. The engine is NOT overheating and it does not throw an error code. However, a couple summers ago, after the misfires/stalls happened several times, the CEL finally did come on along with the VSC TRAC and VSC OFF lights. I was then told by a couple of mechanics that the bank 2 cat was bad and needed to be replaced. I told them that the cat may be an issue NOW, but I didn't believe it was the root of the problem.
Nonetheless, last spring I replaced the bank 2 cat so that I could get the vehicle registered, but I was skeptical the issue had actually been fixed. Sure enough, less than a month later, as soon as the summer arrived, it misfired and stalled in the hot afternoon sun as I tried to accelerate out of a stop. The only time it has ever stalled is in the summer, after I've been driving in the hot afternoon sun, and I come to idle.
Yesterday, it misfired and stalled for the first time this summer, concurrent with the first heat wave of the summer. Oddly, it happened while I was to 50 mph on a highway, but I was going downhill and was not on the gas so the engine was running at low rpms, similar to idling. Unfortunately, this morning, within a few minutes of driving it, the CEL came on along with the VSC TRAC and VSC OFF lights. I haven't checked the code yet, but I'm going to take a wild guess that one of my cats is bad, again, and I'll need to replace it, but it's not going to solve the real issue. I can talk to 10 more mechanics and none of them are going to have a clue what to do other than replace the cat. Yes, I'm frustrated.
I then have to sit on the side of the road for 10 - 30 minutes, in 100+ degree sun, after which it will start right up as if there was never a problem. I put in a new OEM fuel filter before last summer and that had zero impact on the issue. As soon as the summer hit, it misfired and stalled again. The engine is NOT overheating and it does not throw an error code. However, a couple summers ago, after the misfires/stalls happened several times, the CEL finally did come on along with the VSC TRAC and VSC OFF lights. I was then told by a couple of mechanics that the bank 2 cat was bad and needed to be replaced. I told them that the cat may be an issue NOW, but I didn't believe it was the root of the problem.
Nonetheless, last spring I replaced the bank 2 cat so that I could get the vehicle registered, but I was skeptical the issue had actually been fixed. Sure enough, less than a month later, as soon as the summer arrived, it misfired and stalled in the hot afternoon sun as I tried to accelerate out of a stop. The only time it has ever stalled is in the summer, after I've been driving in the hot afternoon sun, and I come to idle.
Yesterday, it misfired and stalled for the first time this summer, concurrent with the first heat wave of the summer. Oddly, it happened while I was to 50 mph on a highway, but I was going downhill and was not on the gas so the engine was running at low rpms, similar to idling. Unfortunately, this morning, within a few minutes of driving it, the CEL came on along with the VSC TRAC and VSC OFF lights. I haven't checked the code yet, but I'm going to take a wild guess that one of my cats is bad, again, and I'll need to replace it, but it's not going to solve the real issue. I can talk to 10 more mechanics and none of them are going to have a clue what to do other than replace the cat. Yes, I'm frustrated.