running weird at idle all of a sudden with clicking noise

[thebeedeegee]

1999 LX with 199k miles. Cranked it up today and the truck was surging at idle. Popped the hood and there was a slight clicking noise coming from the front top half of the motor. Thought maybe the PCV valve? When I put my hand on the part pointed out in the photo I can feel the clicking. What is that part exactly? No CEL, just idling weird.

 

[Jeremy9A]

That is part of the throttle actuator. This guy explains the system pretty well in the video.





EDIT: fixed the link to embed the video

 

[thebeedeegee]

That is part of the throttle actuator. This guy explains the system pretty well in the video.





EDIT: fixed the link to embed the video

Thanks man, I'll look into that.

 

[thebeedeegee]

So after watching his vid my clicking sounds exactly like the sound of the clutch in that little throttle body motor when he tests it. Maybe that motor isn't engaging properly to open the butterfly at idle? The motor revs fine but idles wrong.

I'm wondering if I could run alligator clips to those pins on that electric motor directly from the battery to tests it can still open the butterfly properly or would that blow it? Does it take 12v or something like 5v from the ECM? I can't figure out exactly what tool he is using to do this at 7:46

 

[Jeremy9A]

I'm wondering if I could run alligator clips to those pins on that electric motor directly from the battery to tests it can still open the butterfly properly or would that blow it? Does it take 12v or something like 5v from the ECM? I can't figure out exactly what tool he is using to do this at 7:46

Hopefully someone else will chime in here. I'm not very familiar with these systems beyond what the video showed.

 

[thebeedeegee]

I cleaned the MAF and throttle body today. Tb was definitely dirty. When I started it up the problem was slightly better, but it still idles kind of jumpy and you can hit the motor on the throttle body clicking. It revs fine. I haven't heard of that TB actuator failing before.

@2001LC have you ever seen this before?

 

[2001LC]

I cleaned the MAF and throttle body today. Tb was definitely dirty. When I started it up the problem was slightly better, but it still idles kind of jumpy and you can hit the motor on the throttle body clicking. It revs fine. I haven't heard of that TB actuator failing before.

@2001LC have you ever seen this before?

I've not. But years ago, some felt the need to avoid T-body cleaner from being sprayed into where axle of butterfly penetrated the T-body into motor and gears. They felt it would harm the gears, washing out the permanent lube..

BTW:l I'd start by disconnected the negative post of battery. Than disconnect MAF to CLN. Finish job by connecting battery last. In the 03-up I CLN T-body after connecting battery, and hold open butterfly by depressing gas pedal.

 

[thebeedeegee]

Did it again today. Very bad response off idle and acceleration felt reduced. Once it warms up it runs as expected

 

[2001LC]

It may be, a bad T-body motor assembly. To hear it clicking when just idling, is not normal.

But also is engine properly tuned. i.e air filtration, spark plugs, coils, vacuum lines, etc all as they should be. I can see one vacuum line clip out of place, rear of air pipe. That in itself is not likely issue here, as hose looks sung. But I does indicate all not as it should be. Very often the vacuum line coming from vane pump idle-up control is not connected to air pipe.

 

[thebeedeegee]

It may be, a bad T-body motor assembly. To hear it clicking when just idling, if not normal.

But also is engine properly tuned. i.e air filtration, spark plugs, coils, vacuum lines, etc all as they should be. I can see one vacuum line clip out of place, rear of air pipe. That in itself is not likely issue here, as hose looks sung. But I does indicate all not as it should be. Very often the vacuum line coming from vane pump idle-up control is not connected to air pipe.

Thanks I will check these out! Hopefully it's not the motor that thing looks expensive

 

[2001LC]

I've a 2001 I'll check today if any clicking, to make sure not normal. But I've never noticed clicking. Reports in mud, seem to be mostly in 98-99, with T-body issues. Most replace the whole Throttle body.

 

[TLCPNW]

Mine clicks fairly loud when changing idle rpms, but I don't notice any throttle body issues. Figured I'd mention it (hopefully my TB isn't going out - I have cleaned it a few times and might have removed the grease for the butterfly like you previously mentioned).

 

[2001LC]

I checked both a 2000 & 2001. Neither clicked while idling. I did not let warm up, just started and checked for clicking.

 

[thebeedeegee]

I checked both a 2000 & 2001. Neither clicked while idling. I did not let warm up, just started and checked for clicking.

Thanks for checking that. Guess I'll check for vacuum links and then think about replacing that motor or the whole TB

 

[bouncylexus]

I think I am having the same issue. Rough idle. Usually goes away after the engine warms up. Clicking from that same area. Definitely interested in what fixes your issue.

 

[thebeedeegee]

Throwing a P0171 now. So far all I've done is clean the MAF and butterfly. I guess I'll check all the vacuum hoses next gas cap, anything else?

 

[2001LC]

P0171 is just BK 1. Which may be intake manifold gasket or it's bolts loose. Was starter ever replaced

 

[thebeedeegee]

P0171 is just BK 1. Which may be intake manifold gasket or it's bolts loose. Was starter ever replaced

Is bank 1 the passenger or driver side? As far as i know this is the original starter. I have records from purchase to around 120k miles and it doesn't show it was replaced, but definitely could have been since I didn't buy until 170k and I'm at 199k now.

Also, I did not disconnect the battery after cleaning the MAF, could that cause this?


EDIT- I have 2 codes p0171 and a pending P0174 so it's both sides lean

 

[thebeedeegee]

Could the fuel filter cause only bank 1 to be lean? I checked the intake bolts today and all were tight. I could not find any loose vacuum hoses.

I sprayed some carb and intake cleaner on all the vacuum lines while running to see if I could hear the idle change and couldn't gear any difference. The clicking is mostly gone since the throttle butterfly cleaning, but the code still comes right back after I clear it.

It is only p0171

 

[thebeedeegee]

Could a bad MAF sensor throw this code? Is there a way to test that with a multimeter?

I also realized i dont think i disconnected the battery when cleaning the MAF