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Posted by: nycchef Aug 17 2006, 01:45 PM

73 1.7 d-jet. engine is making what i can only describe as a high pitched rattle (akin to a babys rattle on amphetamines) only on acceleration never on decel and worse in 2nd, 3rd, 4th gear . usually little to no noise in 1st. also idles at 2000rpms which i am figuring on a vacuum leak i can't find. have removed the aar and decel valve and capped those lines solid. power in upper gears seems to diminish. that being said. help!

Posted by: rmital Aug 17 2006, 01:51 PM

...you have such a way with words Richie...

Timing is way off? Pinging akin to a baby's rattle or as decribed to me, a can of rocks being shaken.

Posted by: ptravnic Aug 17 2006, 02:00 PM

Maybe there's a baby on amphetimenes in your front trunk shakaing a rattle?

I'm sure our collective knowledge will whip it into shape on the 26th

Posted by: nycchef Aug 17 2006, 02:09 PM

[quote name='ptravnic' date='Aug 17 2006, 12:00 PM' post='754403']
Maybe there's a baby on amphetimenes in your front trunk shakaing a rattle?

don't think thats it, i keep my crank addicted infants in the nissan. could it be the timing?

Posted by: ptravnic Aug 17 2006, 02:23 PM

Could be lots of things... Prob need to start from the top of Brad Anders' FI troubleshooting checklist... Maybe catch something simple which has been overlooked up to this point?

-pt

Posted by: bd1308 Aug 17 2006, 02:26 PM

well I had a rattle sound in my engine, turned out to be a valve seat dropping/rattling

Posted by: nycchef Aug 17 2006, 02:47 PM

[quote name='bd1308' date='Aug 17 2006, 12:26 PM' post='754439']
well I had a rattle sound in my engine, turned out to be a valve seat dropping/rattling

o.k now i'm worried how do i find out if it's a valve seat?

Posted by: bd1308 Aug 17 2006, 02:51 PM

Hey that was just my thing--could be different.

With me it rattled and I thought "my tin is loose somewhere"


Two weeks later it quieted down, and BAM!

Take the head off of the side with the noise and you'll see. Good thing to do anyway.
b

Posted by: nycchef Aug 17 2006, 02:58 PM

i am planning to either rebuid or relace the engine after the season maybe october. if it's the seat how bad of an idea is it to drive it till then .i can always turn the radio up.

Posted by: bd1308 Aug 17 2006, 03:02 PM

If its the seat...lets see.

I think august i got the engine running. ran till may?

Dropped seat+ valve embedded in piston. Hole too, dont know why.

Make sure you're running everything OK, check timing. Ping sounds like someone dropped a nut into the fan housing.

b

Posted by: Dr Evil Aug 17 2006, 03:05 PM

Damn, Rich. Cant leave you alone for a few days

We set the timing dead on when I was there last. The only way it would be off now would be if the dizzy were loose or the shaft in the dizzy had some play in it.

I am having a hard time hearing the sound in my minds ear that you are trying to describe and I am all out of babies and meth

It actually sounds like it may be a tranny issue as it is dependent on what gear you are in. A valve seat dont give a damn if you are in 1 or 5th it is gonna sound the same and horrible. This is all based on what I am getting form your description. Decell is less stressful on the tranny, acell puts stress on the parts that fail and cause this noise.

Looks like I have another patient on the way.....

I am doing my best to keep on top of my studies so I can try to make it our the 26th. If someone has a spare tranny you can barrow we could swap it and pull the stack on the one you have. If you can get it to me I can get it back in a week depending on what parts it needs.

Posted by: nycchef Aug 17 2006, 03:07 PM

thats what it sounds like. i will re-do the timing, before i panic, right after i check to see if i did drop a nut into the fan housing . thanks a lot for your help. rich

Posted by: Dr Evil Aug 17 2006, 03:07 PM

Timing could give you a hard time on accellaration. For internal cylinder/head problems you can check compression on all cylinders and let us know what the numbers are.

Posted by: bd1308 Aug 17 2006, 03:13 PM

Nevermind my therory.

Evil's right...

PInging is my guess now. Sorry i didnt read the whole thing.

I guess I focused on the babies and meth.

b

Posted by: nycchef Aug 17 2006, 04:15 PM

dearest dr. evil. NOTHING would make me happier than to just drive the damn thing. this noise started the other day without any assistance from me. also we adjusted the valves after we did the timing would that not affect things. missing you awfully. sincerely. me. P.S. study hard the science of mental disease. i am going to need that more than that emergency room stuff.

Posted by: Dr Evil Aug 17 2006, 05:46 PM

Hey Richie,
Adjusting the valves would not effect the ignition timing. The valves should be fine, too.

If you think through the symptoms systematically you will rule out or in what it could possibly be.

The facts as I am seeing them:
- Happens on accell not decell, is dependent on what gear you are in, and was sudden in onset:

On accell your timing does change by increasing the degrees BTDC and if it were off it could cause predetination by not increasing enough. The thing is is that this problem was sudden. For your timing to have gone out instantly it would need to have something fail. Since you now have a vacuum leak you may wish to check the connections on your vacuum advance can to see if this is not the fault. I would suspect if this were the case that you would also be experiencing backfiring pretty bad.

For the tranny, accell is when it is needing to push the 2000+ lb car thus it is when all of your internals are being stressed the most. On decell your tranny is only pushing the internals and the clutch disk so it is not nearly as stressed. Also, you stated that he noise is gear dependent. This typically will rule out your engine. If you rev your engine to a high RPM and hear the noise with the tranny in neutral you have effectively isolated the problem to the engine for most problems. If the noise does not happen, and thus only happens when the tranny is hooked up to the engine pushing the car then you ahve isolated it to the tranny. Do these checks and get back to us so we can isolate it further.

Be warned, there may be more than one problem So isolation may be a bit difficult at times, but this should be enough info to get you into trouble.

Posted by: ptravnic Aug 17 2006, 08:24 PM

I had a bad vacuum advance once - played hell trying to figure that one out... That was pre internet days (aka the dark ages). Then the plenum seam was cracked, and the AAR wasn't closing due to a bad sensor and so on and so on...

Do you know what pinging sounds like? That's kinda like a rattle, happens on acceleration. Not sure why a stock 1.7L would have pinging but maybe try premium gas & see if the rattle goes away... Premium gas will be less apt to ping.

Posted by: Dr Evil Aug 17 2006, 09:42 PM

Found this and thought of you, Rich

http://video.google.com/videoplay?docid=8947053071284110373&q=dog+chasing+tail&hl=en

Posted by: ptravnic Aug 17 2006, 09:53 PM

Posted by: nycchef Aug 18 2006, 05:54 AM

at least the dog knows where it's tail is. so where are we?...check the timing,vacuum advance, tranny, cht, change to high octane gas, sacrifice a chicken and keep my fingers crossed. that seems simple.

Posted by: bd1308 Aug 18 2006, 07:41 AM

73 1.7 was the lower compression 1.7 that ran on regular gas, shouldnt ping.

How do I know? I have one. Paper round air cleaner and all.

b