Got a rattle

[cougar9150]

Well as I seem to make a step forward I get knocked back 2. I have noticed a couple times lately that when I have the car under a heavy load (yesterday passing on the highway) I'll get an occasional rattle at higher rpms.

I have only had it happen on a few different occasions in the last couple weeks, only while under a decent load and of course when I'm not datalogging.

First thing I did each time was look at oil pressure gauge and it was reading right around 75psi (it's a working gauge not the factory one). Gauge seems to read fine in all of the normal ranges, (once engine is warm 25psi at idle, approx 50 psi cruising, etc...) and I just changed the oil less than a week ago w/Motorcraft filter and Mobil 1 5w-20. Don't feel any loss in power, no blue smoke, or pinging.

When I had the timing cover off about a year ago the chains and guides looked good with no overly pronounced wear but I did install new tensioners just to waste money (not really just was misinformed before I purchased the parts and since I had the engine apart...).

I have been having trouble with my trans or trans tune which I think is related to the TC and not the Trans itself. Wasn't sure if a TC would rattle if it was starting to fail and it doesn't misbehave at light to med loads. Also the rattling didn't sound like it was coming from the trans tunnel but from under the hood so that is why I wasn't really expecting that to be the culprit on this problem.

Just wondering what I may be seeing as starting symptoms to a larger possibly costly problem.

[Krytin]

Is it detonation?
How confident are you in the last tank of gas as far as quality goes?
Hope you don't have any major problems!

[ntd]

These cars like to spark knock in high gear and the TC locked IE high load and too aggressive timing/poor gas, you think it might be spark knock and not a engine rattle? what is the timing when this happens?

[cougar9150]

Is it detonation?
How confident are you in the last tank of gas as far as quality goes?
Hope you don't have any major problems!

I only fill up at 2 stations by my house, a Chevron normally and a Shell when it's still to early for the Chevron too be open. I haven't gotten a bad tank of gas from either in the 8 years I've been using them.

Did sound like detonation almost like a giant can of spray paint under the hood. Sounded similar to the infamous cold start rattle, just louder and at 6000 rpms.

Was kind of hoping on ruling that out as I have new plugs and COPs all less than a few weeks old (I plan on double checking these this weekend) and am only N/A so I should have plenty of room w/my stock fuel pump. We didn't see anything when it was tuned a while back that would make me guess something is/was failing in those departments.

I'm also going to clean the MAF and take a look around for any other possible issues ( I need a damn borescope) this weekend.


These cars like to spark knock in high gear and the TC locked IE high load and too aggressive timing/poor gas, you think it might be spark knock and not a engine rattle? what is the timing when this happens?

Not sure as it hasn't happened when I have the datalogger hooked up of course. Though we set the knock tables to be fairly conservative during my tune so it may be the issue at higher rpms with an actual load and not on the dyno. Guessing a trip back to my tuner is in short order.

Getting a quote to get a rebuild at a reputable local engine shop. Asked for best case and worse case quotes. Really hoping it doesn't come to that though as it will mean no boost till 2012.

[babbage]

but I did install new tensioners just to waste money lol - that was funny (how many miles please?)

You said rattle and I thought of broken up cat substrate material.

[cougar9150]

but I did install new tensioners just to waste money lol - that was funny (how many miles please?)

You said rattle and I thought of broken up cat substrate material.

The car had around 60k at the time I yanked the motor to fix the multitude of oil leaks it had.

[ntd]

Not sure as it hasn't happened when I have the datalogger hooked up of course. Though we set the knock tables to be fairly conservative during my tune so it may be the issue at higher rpms with an actual load and not on the dyno. Guessing a trip back to my tuner is in short order.
.

With my car last year the timing tables were fine on the dyno but on the street it would intermittently spark knock on light accel going up a hill. Livernois swore up and down the tables were fine until I took Dan Millen for a ride and made it happen

[cougar9150]

With my car last year the timing tables were fine on the dyno but on the street it would intermittently spark knock on light accel going up a hill. Livernois swore up and down the tables were fine until I took Dan Millen for a ride and made it happen

May just have to do that with my tuner. What values would you recommend to datalog? Just starting to get used to the SCT vs my old predator and not sure of some of the acronyms.

A little nervous as it didn't do it when I first got the tune. Did install a new filter, plugs, and cops since then but it took another week or more before it happened the first time.

Have had a ton of bad luck with this MM and am becoming overly gun shy. Seems whenever I fix one thing, something more expensive breaks.

[ntd]

Never caught it on a datalog just figured out how to recreate it with Dan in the car. Call you tuner explane the problem and figure out what they would like to see in the datalog