mmcpeck

Went out this morning to get breakfast, came back, pulled in the driveway and heard a loud clicking or almost knocking at idle from the front of the engine. ('92 Pickup)

Lifted the hood, and I could swear it sounds like it's coming from the front of the P/S pump. It increases and decreases as you increase and decrease the throttle, but is real hard and steady at idle.

Is this a symptom of the P/S pump going? I have never heard one make this noise. The pulley does not feel loose at all, thought maybe it was the bearing in front of the pump for the pulley, but I think it would be a fatser knocking than this. It is a slow, steady, loud knocking noise at idle.

Doesn't sound like it's coming from any part of the engine, like under the timing cover or anything, just from the P/S pump.

Thanks.

mmcpeck

Anyone ever have a P/S pump make this kind of noise? Can seem to narrow it down to anywhere but the pump.

Kiroshu

I think its called the um.... don't quote me on this but the axuilary air valve over there near ur pump thats bad and making that noise...... they tend to go back on 3vz-e's It kinda looks like ur egr but smaller.... disconnect the vac line to it and it will prolly stop....

mmcpeck

Thanks Kiroshu, I will give that a shot in the morning.

I also thought it was the P/S pump because when I would turn the wheel at idle it would stop momentarily and then come back as soon as I stopped turning the wheel. But I guess if it's vaccuum related turning the wheel could lower the engine vacuum a bit and the noise could stop.

Kiroshu

Usually if a p/s pump is bad or going out it will make a terrible wining noise....

mmcpeck

Yeah that's what I have always heard a bad P/S pump do too, but this sounded so much like it was coming from the pump that I thought maybe I had just never heard a pump do this before.

Couldn't wait until morning to check it, so I just went out and started it up again and it didn't do it, drove it around the block and it started doing it slightly. Doesn't sound like it's coming from that aux air valve, more like it's coming from below that down towards the pump. It sounds like metal hitting metal, but a hard knock, like a hammer hitting a solid piece of metal.

Is the main vacuum line to the aux air valve the one that is underneath it, that comes from the EGR?

Kiroshu

Ah is called the AS reed valve now i remember.....i can;t remember where the vac line comes from but the valve should show it self right kinda behind the P/s pump on the left corner of the intake chamber....... does it get worse with increased RPMS? might be a rod knocking.... i hope not...

mmcpeck

No it's not a rod, it is outside of the block, you can tell it's not from the engine itself, you can tell by the volume of it that is is right in that area by the P/S pump.

I totally see where that reed valve is, sitting right there on top of the timing cover. There are two lines coming off the top of the valve and one line coming off/going to it underneath, that comes from the EGR.

It didn't do it as bad just before as it did earlier today, but when it did, it would increase with RPM. When I was just out there before I put my ear on and around that valve and it didn't sound like it was coming from there.

I can tell this is gonna be frustrating.

Kiroshu

indeed... try and post a vid of it maybe?

mmcpeck

Yeah if it starts up loud again tomorrow, I will try and get a video of it up here.

Thanks.

Team420

exhaust leak? I had an exhaust leak from my egr once, and I thought I had a knock... once i found/fixed the leak...the knocking/tapping went away

Kiroshu

^ that would have to be a major leak lol

mmcpeck

I will take another look, but I looked all around the EGR and felt around it, listened with a screwdriver, and didn't hear anything around the EGR, but I'll look again.

Team420

actually... It wasnt that big a leak... I just didnt tighten the bolt holding the ger to the tube enough... couple extra turns, and the sound was gone!

Ya...I'd check ur manifolds, and anything else exhaust related... could even be the pair/reed valve thingy?

Kiroshu

Ah loose bolt indeed.... a loose bolt would be pretty good leak.. eh anyway.... yea the only thing else it could be is the Pair reed valve like team said....

Kiroshu

not unless theres something vibrating and hitting the engine or somethin.....

Guardian_Saint

Also check your crankshaft bolt. Mine was loose that was making the tapping noise. I got it bolt in and the sound was cured...

mmcpeck

Yeah it's not an exhaust sound at all, it is a metal knocking sound, not internal like a rod, definitely not an exhaust noise from a manifold or anything else.

It is hiding now, either not doing it at all, or doing very slightly. I will probably have to wait until I take a nice long drive to work tomorrow. It started yesterday after about a 1/2 hour of running/driving.

camo31_10.50

i believe before i go about rippin the 3vz out of my '92..i'll make sure everything rotating is tight..LOL..mine has a knocking goin on but im about 95% its a rod..or well rods..lol thing is......the guy took it to a speedylube type of place (sticker on the window tells when the next oil change is due..which was about another 50miles than what the odo says right now) so i mean....there would have had to be an oil leak and the bearings not getting oiled properly.

do bearings just go bad??? the runner has about 160,000 miles on it or so...and he kept up with oil changes and used synthetic i believe....

idk just seems kinda weird for a motor that has NO EVIDENCE of an oil leak....have bearings that go bad?

camo31_10.50

sorry about the hijack buddy!..i hope your problem isn't as serious as mine seems to be!!!