Engine noises - Video Attached

[proto17]

Folks,

I am working on race preparing an 88 535i. There are noises that worry me. Lots of valve noise (I hear that noisy is okay on these cars), possibly a sucking sound, and some pseudo grinding noise. Anyone able to identify the noises?

https://drive.google.com/file/d/0BzpbYv ... sp=sharing

Thanks in advance!!!

EDIT: Race = Lemons!

[Blue Shadow]

sounds like something is sliding uncomfortably on something else as it spins.

Get a broom handle and put one end on the item you want to listen to and the other end on your ear and pinpoint the location of the noise.

Do not get the broom handle in the moving parts. Any long solid sound transmission device will work if you don't have the right broom handle.

[TheYoungSir]

Definitely need a valve adjustment, that will make most of the ticking go away. The fuel injectors should be the louder than the valvetrain, at least at idle.
Sucking sounds I usually find to be vacuum lines. Pay special attention to the thermostat line (looks like the kickpanel/knee bolster was removed) and the intake boot.
If Blue Shadow's broom handle trick doesn't help you enough, put on some earmuffs and hold one end of the stick to the side of the earmuff. It really helps you pick out whatever sound you're trying to hear.

[proto17]

Thank you both for your input

I'll try that out on Saturday (can only work on the weekends)

I actually just replaced all of the vacuum lines that I could see. The large rubber part on the intake (I assume this is the boot you mentioned) is incredibly cracked. I did spray carb cleaner all around the areas that looked cracked and the RPM never changed. Does that mean it's safe to assume things are okay there?

Thanks again!

[TheYoungSir]

If it looks cracked, it is. I would replace it with an OEM/dealer part posthaste (Lemforder would be good, but I didn't see one from them when I replaced mine). It's far more important than any vacuum line, as when those cracks really open up, it's enough to cause some serious running issues. Right now, it's probably the source of your whooshing sound. That's how I knew when mine died a few weeks ago.

As an aside, I've had poor luck with the carb cleaner trick. Didn't catch things that my homemade smoke machine made pretty clear.

[proto17]

I just ordered all new plastic bits for the intake Hopefully that makes some of the noises go away and perhaps the idle a little smoother. Lots of misfires right now =\

[trevmmeister]

If you're taking that thing on the LeMons you might as well baseline it. Actually if you plan on taking it to the gas station, you should baseline it.

You said lots of misfires, what is the condition of all ignition components? Wires, plugs, coil, cap and rotor? While youre doing the boot, check the air filter too, zero in the throttle plate and zero in the TPS after that.

[proto17]

I just ordered all new plastic bits for the intake Hopefully that makes some of the noises go away and perhaps the idle a little smoother. Lots of misfires right now =\

The distributor and rotor, and spark plugs were changed. Also checked to make sure that the compression was good, and it was bang on. It doesn't begin to misfire much until it's warmed up. I checked some of the temp switches and they seemed to be reading pretty accurately.

Is zeroing the throttle plate and tps covered in the Bentley manual? I don't have it with me right now.

Thanks for the advice!

Oh, and the water pump was replaced this weekend, but I still don't have everything back together. Turned out that I had to pull the pump along with the fan and clutch as one unit. Had to make a tool to remove the freaking fan clutch nut... all of that assuming that the water pump was making one of the suspicious noises. Besides, doesn't hurt to have a new water pump for racing right

[proto17]

Okay, so the rubbery bits have been replaced (both intake boots and all vacuum lines). I was still hearing a sucking like sound so I made my own smoke machine

Plastic paint bucket, tin paint can, 2 hose adapters, and 20 feet of rubber hose. Put some mineral oil in the tin, heat it with a torch (mapp gas), cover the plastic bucket's lid, and voila! Blow in one hose, smoke comes out the other.

Anywho, I covered the intake elbow with a rubber glove (to be able to see that there is pressure) and hooked by smoke machine up to the fuel pressure regulator vacuum line (removed it from the FPR). The only place that I was getting smoke from was the throttle body. Oddly (to me anyway) the smoke was coming from where the rod that holds the butterfly valve comes out either side of the throttle body. After hooking everything back up properly, I started the car and sprayed carb cleaner on both sides of the throttle body. No change in RPM from idle. I'm very confused. Is this okay? Was I maybe applying too much pressure to the system?

With the intake boots replaced, it does seem to run better, but it still misfires a lot once warmed up. My only other idea is to replace the temp sensor on the radiator.

[trevmmeister]

The CTS feeds the ECU the signal it needs to adjust the mixture, but could that cause a misfire, i dont know. Its also not on the rad, its on the coolant passage leading from the thermostat, next to the thermo-time switch.

[TheYoungSir]

The only place that I was getting smoke from was the throttle body. Oddly (to me anyway) the smoke was coming from where the rod that holds the butterfly valve comes out either side of the throttle body.

I also got a little smoke there when I tested my car at a pretty low pressure. I suppose it could be rebuilt/refreshed to help clean that up, but it's so small, it won't have any effect. Maybe make sure the TPS is properly tightened, but beyond that, it's normal.

[proto17]

The only place that I was getting smoke from was the throttle body. Oddly (to me anyway) the smoke was coming from where the rod that holds the butterfly valve comes out either side of the throttle body.

I also got a little smoke there when I tested my car at a pretty low pressure. I suppose it could be rebuilt/refreshed to help clean that up, but it's so small, it won't have any effect. Maybe make sure the TPS is properly tightened, but beyond that, it's normal.

Thanks for that. Makes me feel better about the whole thing. Do you know of any place that sells rebuild kits for them? I couldn't even order a new gasket for it from Autozone

The CTS feeds the ECU the signal it needs to adjust the mixture, but could that cause a misfire, i dont know. Its also not on the rad, its on the coolant passage leading from the thermostat, next to the thermo-time switch.

I'm really curious because of the fact that the idle is pretty good before the engine warms up. Are there any other sensors that trigger at a certain temperature?