pathology knight

iTrader: (1)

I have a "clickin" noise that seems to be coming from under the driver's side of the dash. think right above your shins. It only occurs under acceleration.

I did some checking on here and i thought it might be an exhaust leak. I got under the car and didn't see anything expect that i think i might be missing a bolt holding on each header (driver and passenger side). I posted a question about it under the "Exhaust" section, but basically there seems to be bolt missing at the far rear, towards the firewall, of the header. There is only one bolt in front of the exhaust tube. this is the same on both headers. Not sure if it's supposed to be like that or not.

If the headers are installed correctly, what else might be making this "clicking" noise? it's fine when idling or coasting. It's just occurs when i'm on the gas pedal.

TPI

An exhaust leak would be pretty apparent if that were the case. From my own experience, the clicking under
load and acceleration is none other than your fuel injectors. It seems fairly pronounced inside the car with the
windows up and the radio off. Outside the car, it is not very noticeable.

The only other thing I could suggest is valve train, You could try a re-lash
and see if that cures your "click" but, I gave you my honest opinion above.

TheExaminer

Have you put a stethascope or something on the FPR? My FPR makes a clicking sound, for a while I thought it was a bad lifter, but no, it was the FPR. It still works fine for now, but eventually I will replace it. But mine did the exact same thing. You could hear it clearly inside the car with the windows up, but not so much in the engine bay. Check for it....

TPI

Never thought about the FPR, hell.. Im curious now too! Nice call.

TheExaminer

Haha, I never would have either. I started listening at all the cylinders at the valve cover and heard nothing, then I noticed it was coming from the fuel rail, then I just followed it back to the FPR. I'm not sure what makes it do that, bad diaphragm or what IDK--but the clicking was loudest at the FPR. Go figure.

TPI

Well, that is the funny thing.. It only really "clicks" under load while
moving which is pretty hard to locate! Either way, It is what it is..

Aaron_SK

iTrader: (1)

It is almost certainly an exhaust leak, albeit a small one.

Start the car cold and let it idle. Put your hand near the exhaust flange before everything gets too hot and you will feel the pulse of the leak.

TheExaminer

Hmmm, well, mine clicks more at idle than under load, so maybe it's not the FPR. My clicking increases with rpm though too. Take a listen when you get a chance, that's all you can do. Lol

pathology knight

iTrader: (1)

i found out that each header only has 5 bolts, not the 6 it's supposed to have.

it should be: .0=.00.=.0. but the last bolt is missing, the one closest to the firewall. I'm hoping i can take the car in (i don't think i can get a bolt in there) and get it fixed and hopefully solve my problem. It's a tight squeeze, but i might give it a try.

Also, what's a "FPR"?

TheExaminer

Fuel pressure regulator. Mine clicks in a way similar to what you described.

pathology knight

iTrader: (1)

i'm not much of a knowledgeable mechanic. Where's the FPR located and is it easy to change out?

TheExaminer

It's not too bad, an hour or two of turning wrenches, and that's if you take your time. It's under the plenum (assuming you're running tpi), near the back of the intake base in front of the distributor. Looks like a little ufo or something, is connected to the fuel rails and has a vacuum line. You have to take the plenum off, no big deal. Four bolts at the throttle body, (don't have to remove the TB from the engine, just let it sit there on its hoses) and then all the plenum to runner bolts at the top, there's like 6 or 8 of those. Unplug the brake booster hose, lift the plenum enough to unplug intake air temp sensor from its connector and lift the plenum all the way out. Most of the time it's the FPR rubber diaphragm that fails, so that's what you replace. The top of the FPR has little "security" torx head screws--torx with a little "button" inside the torx inset. I forget the size, but you have to get a special torx wrench for them, they are cheap and can be found at any hardware store. But this sounds a lot more complicated than it is, taking the plenum off is pretty easy. I took mine off for the first time last year, and was surprised at how easy it was. LOL But use a long screwdriver against your ear (carefully!) or better yet a stethoscope to try to pin down exactly where the noise is coming from. That lack of an exhaust bolt could be it, but it wouldn't hurt to listen around at everything else while you're in there.

TheExaminer

Here's where it is. This guy has taken one set of runners off, and the throttle body is gone--you don't have to take it down this far, but this is what it looks like. BTW, forgot to mention that the FPR diaphragm is spring loaded, so if you did need to change it, keep one hand on the cap to keep it from flying off and hitting you in the nose while you're unscrewing it....lol

Aaron_SK

iTrader: (1)

Once the gasket is blown putting the bolts back in will solve nothing.

You need to pull the headers away from the motor and replace the gaskets. I strong recommend using RemFlex gaskets. They are pricey but well worth it. You're in Washington so your local Baxter's will carry them.

There is absolutely no way a fuel pressure regulator will cause an audible clicking noise on a thirdgen. Injectors can push back a bit, but audible in the cab? No.

TheExaminer

LOL, tell that to mine. Stethascope right on it, and it clicks. It's not the same click as the injectors, not the same at all. It's in the FPR, and is loudest there. I thought it was a bad lifter, but you can hear nothing in or near any of the cylinders at the valve cover,only in the fuel rail, and it gets loudest at the FPR. Don't know what to tell ya. One guy on here told me he thought it was a pulse coming up out of the fuel pump, but I doubt it, not from that far away. You can't hear it very well in the engine compartment, but in the cabin it's loud and clear and is clearly coming from under the hood.

TPI

I respectfully disagree sir. And, I'm still siding with injectors as the culprit.

TheExaminer

As far as my noise goes, I thought injectors too, but the problem with that is that not all 8 are firing at once. It's not a cacophony of 8 clicks mixed together with different timing, but one steady click to itself. The clicking noise that's loudest in my FPR is a clicking noise all to itself that is different than the injectors, way, way louder than an injector. It's just about loud enough to to deafen you when you have the stethascope on it, and it's loudest point is the FPR. Don't ask me to explain it, I can't. I'm just saying what the noise is doing. The car runs fine, no problems, just clicks, and it's not a lifter that I can tell. The noise is totally absent from any point on the valve covers.

pathology knight

iTrader: (1)

thanks everyone.
i might try and replace the FPR (it's old anyways) and see how that goes in addition to the new header bolts and gaskets.