High idle after timing belt and water pump?

NJshadow93

New member
I picked up my truck yesterday morning from getting the timing belt and water pump replaced. They also replaced the tensioner and idler puller. When I started it up, I was surprised to see it idling at 1600 RPM! I brought it back in, the tech said he repaired some wire and cleaned some deposits and that maybe something wasn't sealed correctly. So he cleaned more deposits, brought it back out to me and said it was idling 2000 RPM higher than it should. He said the ECU needs to re-learn the truck after he repaired the mystery wire and it should be fine. If it's not back to normal in a couple days to bring it back.

Driving it was a bit different, felt jumpy in some cases. Lately however, the idling has gone down, but still seems a bit high. My question, has anyone else experienced this?
 
Register to hide this ad
i didnt experience anything like that, once i replaced the timing belt and all internals truck fired up sounded normal ran a little smoother with the new idler bearings and tensioner bearings but that was it. is there any other details on the wire he mytseriously connected?
 
Not really. He said he had to take the serpentine belt off to do it. And he didn't charge for it because it wasn't on the receipt. Apparently, the wire was damaged and on it's way out and he wanted to repair it. Other than the high idle, it runs fine. Still responsive, great power. Thinking about calling the dealer and finding out more info on the wire.
 
I did not experience a high idle after my TB WP change.

If it's getting better, maybe he was right about the ECU learning. Hope he is anyway.
 
I did not experience a high idle after my TB WP change.

If it's getting better, maybe he was right about the ECU learning. Hope he is anyway.

Thanks, me too. I don't know how sure he seemed though. At least he acknowledges it's idling too high. He was trying to tell me that it would only waste a little more gas and that's if I let it idle for like an hour. I don't care how much more gas it wastes, whether it is a little or a lot, it shouldn't be wasting any more than it did before. Obviously a higher idle isn't normal.
 
Not really. He said he had to take the serpentine belt off to do it. And he didn't charge for it because it wasn't on the receipt. Apparently, the wire was damaged and on it's way out and he wanted to repair it. Other than the high idle, it runs fine. Still responsive, great power. Thinking about calling the dealer and finding out more info on the wire.

the only wire im aware of in that general area thats in risk of damage would be your cam positioning sensor wire, if that was cut or damaged and then repaired then the ECU will certainly have to relearn whats going on. The ecu reads cam posioning off of resistance in the wire. if he just put a wire connector on, then the resistance changed so the ECU has to make up for that difference the cam positioning sensor wire is located at the top right cam pully timing belt cover it should have a grey wire connector, that on one end sends a wire into the timing belt cover, and on the other end sends wires back into your main engine wiring harness. other than that i'm still clueless lol my connector for that wire was damaged from not being tied down properly i zip tied it back away from the fan blades after re assembling everything. but the actual wires were ok in my case.
 
You think I'm at risk of damaging major components? I asked the tech and he said no, but I'm no car expert and I'm not sure whether a high idle can be caused from a big problem or cause serious problems itself. I would just hate to be one of those who's vehicles gets messed up by a shop or a dealer
 
I agree with aha about the cam positioning wire. That along with the connections on the alternator, and the AC compressor if he removed it are really the only wires he would have come in contact with unless he just spotted something else. I would probably lean on the wire as a possibility since it is a likely cause, but I wouldn't put all my money on it.

The other realistic possibility that the belt isn't positioned on the timing marks correctly. The ecu adjusts the timing to match the crank position, and could be over compensating. That would be my most likely cause. I say this because admittedly having replaced many timing belts, I have had a belt slip a tooth in the past.

Both a bad cam positioning wire and the belt being out of position can give you the same symptoms. I know I wouldn't be thrilled with the prospect of tearing it down again to check the timing marks. After I made my mistake, I now take the time to put a little drop of paint on each cam and belt to make a match mark so that I can be absolutely sure I can easily spot if a cam slips. With only having two hands it can be tricky positioning two cams, a crank and a belt.

BTW, did you lose your radio stations and clock have to be reset? If not then your ecu probably wasn't reset.
 
Last edited:
If not electrical, what is the possibility of an issue of some kind with a vacuum line? They won't always set off a CEL but have been known to cause the ECU to do some funny things.
 
It shouldn't take more than a minute or two to figure stuff out. Idle for a 2003 in drive stopped should be around 750RPM. They lowered it in 2005, I believe, to 600ishRPM.
 
It shouldn't take more than a minute or two to figure stuff out. Idle for a 2003 in drive stopped should be around 750RPM. They lowered it in 2005, I believe, to 600ishRPM.

Yeah it's looking for like that now. On the first cold start, it looked like I had my foot on the gas. It was way up idling in park at 1700 RPM. It dropped to about 1300 RPM a by late afternoon. By that night it was maybe 1100 RPM. Today I started it up and it was under 1000 RPM. I'll report back tomorrow. Hope everything is good.
 
You think I'm at risk of damaging major components? I asked the tech and he said no, but I'm no car expert and I'm not sure whether a high idle can be caused from a big problem or cause serious problems itself. I would just hate to be one of those who's vehicles gets messed up by a shop or a dealer

as long as the motor doesnt sound like its got marbles rolling around in the pistons your fine a high idle can't hurt anything (i mean if it were idling at 3000rpm+ i would worry but 1700 at start up is fairly normal mainly on cold start ups. my typical morning start up the motor fires up and idles at 1200-1500 rpm for a good minute or two then drops to the 700-900rpm area, in drive it stays around 600-700 idling with the break on, your probably fine hope it stays running right!!
 
Just thought I should report back...truck is back to normal and running silky smooth! All I did was drive it. I love Toyotas! :D
 
Glad to here it brother! Thanks for reporting back! Could be valuable info for somebody experiencing this in the future.
 

Members online

Forum statistics

Threads
278,316
Messages
3,554,120
Members
248,016
Latest member
Advally Service

Trending content

Back
Top