rough idle
- Thread starter satchel
- Start date
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I changed my serpentine belt over the weekend because it was making noise when it gets cold. To my surprise, the engine is now idling smoother, but its not like it was idling badly to start with. Even my wife notice that the car is now quieter - she usually do not pay attention to this kind of things. So thats maybe one more thing to add into the list above.
Chris
- Thread starter
- #23
So my wife drove it to toyo today and said that the hesitation was much improved, but there was still a little amount. I'm having toyo go over the truck and do the timing belt anyway, and they mentioned they were going to change out 2 of the coils and all the spark plugs. I was going to do the spark plugs anyway, so hopefully all together this will get rid of the issue. I'll post up if it is completely fixed afterwards or not.
2001LC
SILVER Star
Changing out bad coils should really help. Was your check engine light on?
arcteryx
Supporting Vendor
Agreed. Why were they going to change two? Did they pull and inspect them? Perhaps they were cracked? It seems odd that they would change them out if no CELs were thrown.
For plugs, there are 2 types of OEMs, make sure they use one of the two. nothing else.
For plugs, there are 2 types of OEMs, make sure they use one of the two. nothing else.
2001LC
SILVER Star
What our the two types of spark plugs?
arcteryx
Supporting Vendor
2001LC
SILVER Star
Any difference in performance?
Denso came out of mine, so that's what I used. They look so good after 100K miles that I saved them.
Denso came out of mine, so that's what I used. They look so good after 100K miles that I saved them.
arcteryx
Supporting Vendor
I don't know about performance, that would be interesting. I put in Denso's as well. I have talked to a couple of mechanics who state it has to be an Iridium and only one of those two, otherwise it introduces more problems in the 2UZ
- Thread starter
- #30
Got it back from the shop today, all misfire issues seem cured. I'm not sure how much inspecting was done on the coils, but there was never any codes thrown for it. Most of the time that I've pulled a bad coil, it was because I had a misfire and I would pull each coil until I noticed that the engine didn't change when it is pulled and that pointed to the bad coil, but I don't know what their process was. Either way, all fixed up now so I am happy.
Good to hear the rough idle is gone. So, they changed 2 coils and all spark plugs? Which 2 coils and why only those 2?
- Thread starter
- #32
It is gone, yes. I believe it was 4 and 5, I'll have to go back and look at the paperwork. Yes, 2 coils and all spark plugs, because those were the only 2 coils that were bad. Sounds like these trucks burn coils from a lot of the threads I have read. Are you thinking that when one goes bad we should just change them all? At $140 each, I'll just replace them as they go bad on mine I think.
arcteryx
Supporting Vendor
See my post 25. Why/how did they determine those 2 are bad, if no CELs' were thrown? And no, you don't have to replace them all at once, just keep a spare with you. Also, I hope you didn't pay $140 each, you can get them for $60-65.
- Thread starter
- #34
I'm not sure how they determined they were bad. I know how I have determined on other cars coils are bad in the past and it is pretty easy by pulling the coil and seeing how the engine reacts to it, but I didn't press them on what methods they used to determine they were bad being that it cured my hesitation. If they changed out the stuff and nothing got fixed I would definitely be more inquisitive on why they changed them out, but being the misfire is now fixed I'm not worried. for what it's worth, I asked them if it is typical that they would see a bad coil with no CEL and he says it isn't typical, but does happen.
Yes, I did pay the dealer price of $140.
Yes, I did pay the dealer price of $140.
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No, I wasn't suggesting changing them all. Merely inquiring which two were bad and if it was common to have bad coils with no CEL (for future reference).
- Thread starter
- #36
I'll go back and look up which ones for sure. Always good to know. There's certainly ways to check the status of a coil without having a code, i'm assuming they just did the old fashioned way by looking for spark at every cylinder.
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2001LC
SILVER Star
I suppose a gray area exists where coils aren't bad enough to throw a code, but may be one of those contributing factors to poor performance. I've heard same said about O2's here in mud.
I'll bet OP shop has seen often enough they check with something like: TA500 Coil on Plug Tester. Be handy to have one for my toy box.
I'll bet OP shop has seen often enough they check with something like: TA500 Coil on Plug Tester. Be handy to have one for my toy box.
- Thread starter
- #38
I thought the guy said 4 and 5, but just looked at the paper and it was 1 and 6. I would be curious to know if anyone else has had a bad coil without any codes. I haven't read that others have before so I guess it is entirely possible that cleaning the MAF and TB solved the issue and the coils maybe weren't bad or perhaps bad enough yet to throw a code, but as far as I'm concerned, it's fixed and i'm happy.
- Thread starter
- #39
This is the part number on the invoice for the plugs - 90080-91180. When I look them up it just says they are toyota OEM plugs, look to be iridium. Here is one from Amazon http://www.amazon.com/Toyota-Genuine-Parts-90080-91180-Spark/dp/B004T1PEOI
- Thread starter
- #40
Where do you find the coils for $65? I'm on vacation right now so just paid the dealer to get it done, but if I can get them cheaper in the future I will. I'm sure CDan can get me a discount but I would be surprised if it is that much off to get me down to $65. Is it aftermarket?
