ok i still cant seem to get rid of this bloody rattle and it is really starting to do my head in. ok when ticking over cars sounds fine i can rev up the engine and still sounds fine. Now when i take it out for a run all is ok until i push a little harder. as soon as get some boost i get this annoying rattle (metalic). the more boost the louder the rattle. i have checked heat shield around turbos and they seem fine. it seems to be coming from front passenger side. is there anything that i may have missed. iv also checked brake disk plate and also seems fine. :headvswal:headvswal:headvswal:mad::mad:

i used a clamp on the no. 1 plug and powers from battery. also set the tps to .40 but that seem to have sliped to .38 now. will reset it.

 

http://www.blazt.biz/products/images/datascandatadisplay.JPG

 

Is that what you see fella?

 

The far left middle row shows your timing as the ecu reads it from the cas sensor, you need to check with a timing light through the rev range that the timing on the computer and car match to prove they're working together.

Might be an idea to data log the car on a run after proving that. Post the data from the graphs and see if there are any clue from that.

yea thats the readings i get. trying to post the reading i got as soon as my laptop behaves itself and installs flash player. its all going wrong.

Its going wrong for 3 Irish zeds this week mine got hit, Nelson is stuck 50 miles from home waiting for the RAC and yours Richard it always happens in threes:mad:

Theres a bar underneath the car,across the floor pans in the narrow part of body work,is it the exhaust hitting it. Mine did this so i remove the bar.

No idea about the bar bluenik but thanks for the imput. every little helps. ok i decided to have a go at it tonight so took off the balance bar whick to my surprise was very loose on one side (might have been sucking in air there). cleaned all the connections including injectors whick were all green with corrosion and a pipe whick was held together with duck tape. so then i put everythink back together again making sure everything was tight and clean. took her for a spin and even though she is driving better (great actually) the fooking rattle is still there. i then done my data scan again and logged the data which i will post in a few mins for anyone who understands that stuff. no faults were shown though.

 

THANKS TO EVERYONE FOR POSTING THOUGH. THIS REALLY IS A GREAT PLACE AND SOME FANTASTIC PEOPLE IN HERE.

For some reason i cant add the log. All i can say is one o2 sensor is reading at 27 even when i rev the engine is only moves up a little where as the o2 sensor rh is at 57 and moves between 14 and 60 when rev'd. Does this mean anything. The af ratio still says lean. Engine was at normal operating temp.

For some reason i cant add the log. All i can say is one o2 sensor is reading at 27 even when i rev the engine is only moves up a little where as the o2 sensor rh is at 57 and moves between 14 and 60 when rev'd. Does this mean anything. The af ratio still says lean. Engine was at normal operating temp.

 

By the sound of it the left hand O2 sensor might be gone, but this as far as i understand it only affects fuelling at idle and light throttle meaning it'd wouldn't affect fuelling on WOT, as this would be a standard map.

 

IIRC best way to check a O2 sensor is hold the engine at 2000rpm and watch the O2 sensor, its voltage (numbers you've quoted) should flick back and forth 5 times in ten seconds. A small movement in magnitude means the o2 sensor is not responding properly.

 

Yep, see here for the test to diagose if its NG:

http://300zx-twinturbo.com/cgi-bin/manual.cgi?list=efec&dir=&config=&refresh=&direction=forward&scale=0&cycle=off&slide=129&design=default&total=190

Edited June 22, 200916 yr by stenorth

If it's not something stupid like a loose bolt or a panel resonating, i would suggest work through the detonation section on here:

 

http://300zx-twinturbo.com/cgi-bin/manual.cgi?list=efec&dir=&config=&refresh=&slide=42&cycle=off&scale=0&design=default&total=190

 

Even if you don't find the cause straight away, you've already proved that you'll be able to sort like problems like you mentioned so always a good thing!

 

If you get any more information, post it up! :)

ok looks like i have victory. where do i start. ok i added a can of pro boost as i was told by jamie that the octane level might cause. so after doing that with no real improvment i decided to proper check the timing again. this is where the fun started. attached all my leads and lamp and to my amazement my timing was set at 35 degrees BTDC. my jaw dropped. so i set it back to 15 and the rattle decreased quiet a bit but not gane. so i rang a mecanic friend who said that pre ignition is a common problem and suggested that i drop it to between 5 and 10 and see if it makes a differance, which i did and away she went flying. i also noticed that my ECU has a series 1 chip so dropping the timing i was told is the thing to do. i dunno but it worked.

ok looks like i have victory. where do i start. ok i added a can of pro boost as i was told by jamie that the octane level might cause. so after doing that with no real improvment i decided to proper check the timing again. this is where the fun started. attached all my leads and lamp and to my amazement my timing was set at 35 degrees BTDC. my jaw dropped. so i set it back to 15 and the rattle decreased quiet a bit but not gane. so i rang a mecanic friend who said that pre ignition is a common problem and suggested that i drop it to between 5 and 10 and see if it makes a differance, which i did and away she went flying. i also noticed that my ECU has a series 1 chip so dropping the timing i was told is the thing to do. i dunno but it worked.

 

Woop!! Really glad for you mate!

 

Yep that's too much advance, and with the ECU ramping up for the variable valve timing that probably further advanced the timing. Retarding the timing will be a good fix for the moment.

 

The good news is it won't be damaging to your engine as you caught it early and sorted it. The noise is piston rattle because the combustion event is happening before the piston has reached TDC.

 

You should feel the engine has better power than before.

 

What setup do you have on the car engine wise?

 

Also, if you not sure get someone to check the timing against the ecu timing to make sure that the timing doesn't shoot off again!

Edited June 22, 200916 yr by stenorth

RESULT! Excellent stuff :)

i would look at getting the timing and air/fuel mixture checked out first and go from there. Ask jefftt to look at this thread he maybe able to point you in the right direction.

 

Paul

 

 

:d:d:d:d Glad you got it sorted.

nice one bud

slight misfire cause of the 5 degrees timing but its better than the rattle. will let a specialist look at it tomorrow anyway. Thanks for all your help lads its much appreciated.

good news Richard glad you got it sorted.

bad news again lads. rattle is back. noticed it yeasterday morning and got really pissed off with it. so i striped down the cambelt to make sure it was on rite. seems it may have also slipped a tooth so put it on correct double checked it and then checked again. put it all back together re timed it to 15 degrees making sure my tps was at 40 and took it for a run. rattle still there. ( think its laughing at me now). so today i put some spare O2 sensors on it and its still the same. so i am gonna have to bite the bullit and give it to a specialist tommorow. i hate getting beat by something but i just cant fix this one.

Congrats! Youve worried me now, mine does this if you accelerate slowly, but not when you accelerate fast or even on boost, i just put it down to something being lose? Sounds like a really tinny rattle underneath the car on the passenger side? Do you think this could be the same?

 

It shouldnt be really as when ive looked through the service history most of the work was done by Zed World

OOpps sorry for my last reply! Lol

 

Hope you get it sorted anyway

slowly or fast really makes no differance but you can hear the rattle more when you get boost. get it checked by jeff in zedworld to be on the safe side.