Hi Guy's,

Ok so i fitted NEW LIM gaskets was real carefull to put RTV on the block between and around the bottom of the gaskets, torqued up the bolts to spec but I've got the same result! Engine goes straight to 3,000rpm then drops to 500-1000 is very rough and has a very high piched ear splitting squeal! I can't say where it is coming from exactly, it's just coming from the engine. It's not coming from any of the accessories (air pump is spinning free now)
It's exactly the same sound as before no louder no quieter. Any other ideas guys before the whole lot comes off AGAIN!

Speed.

 

I assume that this has been brought up before and you fixed something? It would be great if we could update a prior tread instead of making a whole new thread about the same issue. So to recap...What all did you change before this started? Did it start as a result of something you changed? Has it gotten worse over time? When it drops to 500-1000, does it hold steady down there or does it bounce from 500-1000 to 3000?
Sorry, I dont want to sift through old posts to find the answers...

 

Do you have all the sensors hooked up? I know that my TB squeals very loud without the intake tube hooked up.

 

Yeah sorry Grim i'm not an expert in threads and posts, but thank you for drawing my attention to it i'll make sure I just keep updating my previous threads in future.

Anyway to re-cap, I took my engine out at the end of last year to replace all the freeze plugs. At the same time I was advised to replace all my other gaskets that could be gotten to with the engine out. As it turned out I ended up replacing all the intake gaskets, the oil pan (which was dented) and gasket, the rear main oil seal, cam cover gasket, the EGR valve, the distributor (module and pickup coil) knock sensor, O2 sensor and cat, and lastly the air pump which had frozen solid! The first time I started the motor it raced to 3000rpm and then dropped to 500 then went back up to three and so on whilst making a sound that sounded like air escaping from a balloon when you pull on the end of it if you get me, a high pitched squeal. I thought it was the RTV on the ends of the block so I pulled the LIM again put on new gaskets following the instructions. I tried again and it's still doing the same noise. It will tick over very roughly now between 500 - 1500rpm without stalling but as soon as you touch the throttle it'll rev to 3000rpm again. I wrote notes and took pictures as I took the engine apart and I'm sure I put it back the same with the new parts. I can't say where it's coming from exactly as the sound is sooo loud you just can't get a bearing on it! As the engine seems to want to run i'm pretty sure the noise and the rough running have to be related.

Speed.

 

check your tubing, make sure the rear air lines at the top of the intake manifold (in the rear) are hooked up. make sure that the line to the egr is hooked up, the heater valve vacuum is hooked up, the cruise control vacuum, and the other spider web of vacuums under the intake manifold.

 

Done all that scottie,hoses are back in place. Got me canfused this one.

 

Gasket on the EGR?

 

EGR gasket would not cause this large of a leak. I drove 50 miles with my EGR flopping around and it was no (major) problem. A leak of the magnitude he's talking about would have to be a huge source, such as the original thought of the LIM leaking. I wouldn't think that a couple cracked lines would have the noise that he is talking about, either. I know what a leaking LIM sounds like, and it's nothing like a cracking hose.

 

You're right fork, it sounds like air being sucked between rubber and metal big time! So I'm pretty sure it has to be that RTV? I pulled a spark plug too i forgot to mention, and it was pretty white so I'm guessing lean mixture confirming the air leak? I'm also guessing that the engine is trying to find a correct mixture of fuel/air but can't because of the leak. Don't know if I'm right on that??

Anyway, I'm pretty conviced I'm going to have to pull the LIM for the third time! Do I HAVE to use RTV? I have some gasket sealer called somsonal red, could i use this on the rear block instead and use RTV for the front as i'm pretty sure thats ok.

Speed.

 

Check your injector o-rings, your throttle body gaskets, and where the PCV vet tube connects to the intake bellows and the nipple on the pass side valve cover. Then, when you are done at the front, check the brake booster line, the PCV hose running off of the valve on the driver's side, check all of your vac hose (solid to connection) connections to see if any of your hoses are cracked or damaged. If none of these work, then you might have a warped manifold or something, in which case, this might get to be a little expensive for you.

 

Ah injector O rings, I did have problems putting the injectors and the rail back in, but they all went in and seated where they came out from ok. Is there any way of checking to see if airs getting past or should I buy new rings?
I'm pretty sure all my hoses are ok though. I've been real carefull with the LIM and treated it like spun glass. I did have to have the coolant fitting re tapped at the front of the LIM because the old one broke off! But this was done by a professional engineering works so I doubt that they would have bent it.

Speed.

 

Yeah I was just going to suggest checking the injector O-rings. It seems like the only thing you havent gone over with a fine tooth comb.
You will have to pull out the fuel rail to check them. One might have even fallen off and there might be no seal on one. They should be pretty cheap from the parts store.

 

My o-rings cost me ~$6. If you haven't done them recently, I'd just go ahead and replace them all since you're in there anyways.

 

Thanks guy's, just had a look at some ac delco ones at RockAuto for $20 so I'll order some tomorrow. Didn't notice any of them missing but I guess it can't hurt to change em anyway. Has anyone used anything else other than RTV to seal the LIM and block ends though? Won't be able to reply to any suggestions while tomorow guy's I gotta go to bed, up at 3 in the morning, but thanks for the help so far.

All the best, Speed.

 

Hi Guy's,

An update, ok fitted another LIM gasket (3rd!) but i've got the same results again! Turn engine on straight up to 3,000rpm squeal like hell then stall. Start again back up to 3,000rpm, a little gas to keep it going then it'll settle into a rough idle with a constant squeal. Blip the throttle a touch and back up to 3,000rpm etc. The one thing I did notice this time was after may be 7 mins the temp showed 100'c so I switched off!! The cooling fan wasn't going and the top hose was cold, but the engine was way hot! Got back in the car turned on the ignition (but didn't start) and the temp now said just under 40'c

I've not got more than about 5-7 litres of coolant into the car after putting the engine back in after filling to the base of the filler neck, so i filled the expantion tank before I run it with the intention of filling it as the car ran. Could an air lock of some sort cause this?

I also pulled a plug again and apart from a light covering of soot on one side the plug was very white. I've checked the dizzy and the rotor does line up with the no'1 plug terminal at TDC. The dizzy is a new one from cardone.All vac hoses are good, but I just can't work out what the hells going off.

Has anyone got any ideas because I'm almost out of them.

Speed.

 

Right tried the carb cleaner trick, and at last I'm getting somewhere!
shot some at the back of the engine near the LIM, nothing much, shot some at the front, again nothing much. Then shot it into where the injectors are and the engine rev's went up each time I did it. The squealings still there but I think I may have leaking O-rings? Anyway, cars temp was ok this time and it ran without trying to stall so at least i managed to warm it up. The only thing wrong is the ear splitting whistle! Has anyone elses injectors made this sound?

Speed.

 

Sounds like you may need to replace the injector o-rings. Injectors don't whistle, they click. Is the air filter assembly hooked up, my TB makes a very loud and horrendous whistling sound whithout the air assembly.

 

I've tried it with/without the air cleaner 2.8 but it makes no difference. I thought it was the LIM gasket and replaced it twice, but got the exact same sound. On;y place I get an engine increase is when I spray near the injectors!

 

managed to get the sound on my phone.

http://www.youtube.com/watch?v=RJw-8JjytD0

 

That is bad. Try replacing the injector o-rings and see what happens.