Contour Enthusiasts Group Archives Forums General Troubleshooting knock at 3000 or higher rpms

i have a engine knock at around 3000 rpms and high dont do it at idle and also my secondaries dont open all the time and i have a 1998 SVT

i too have a knock.
i have a '97 v6 duratech w/ 85k. atx.

knock occurs in 1st gear @ 3200, 2nd gear about the same, and in drive it doesn't knock until over 4 grand. idle and non-heavy driving have zero knocks.

any insight would be great.

thanks,

tim.

more info..
i only use high octane. usually from shell.
i know the knock is present at idle as i heard it loud
and clear when cleaning my TB last month.
if it is bearings how labor intensive is that? anyone done that themselves?
i am not finacially in a position to replace my car or my entire engine, so i am trying to resolve all of car's woes.

thanks,

tim.

hey, thats how mine started, but now im sure its the rod bearings, hopefully just one. but i have also herd your timing tensioner could make the same sound, so, but if it is a crank bearing, or a rod bearing, fix it now, it can only get worse!!!!it can be a pain in the arse to do, but it isnt to expensive if you do it all yourself....hope this helps

how many miles are on your cars??

Start out easy by checking the gap on all your plugs.

It's sounding like the dreaded rod knock that's all to common in these engines...

Normally the chain tensioners and/or lash adjusters would make their noise at idle as well (but not always). The bottom end rod knock is easy to tell as it will do it under no load too (free revving in neutral) The chain tensioners and lash adjusters will less the noise under no load.

Checking the plug gap won't help here since the piston would smack the head before touching the plug, though severe detonation would run it white if that's the direction you were hinting at...

my tour has 85k on her. (ever wonder why they are always "hers"?)

i don't know how long mine has been knocking as i usually have the radio up loud, and when its down low its cuz the kids are in the car and then i'm driving like a mature responsible human being instead of the way i normally drive.
i 1st noticed the knock about a month ago while spraying TB cleaner.

i'm glad bnoon chimed in.

direct question...
how does one troubleshoot for rod bearings? is there an exact procedure to decypher these things?

thanks guys

tim.

You may have a dead rod and replacing it may cost a lot of money. It is good to put high octane into the engine even if it takes 89. this helps the engine from over working when you accelerate b/c there is more o2 in the combustion chamber.

also try checking yor spark plugs. i dought that may help, but sometimes you never know. they could be dirty and may need replacing.

My last car had a similar problem and it was due to lack of air in the system (aka a lean system). once i got a new MAF and plugs, the problem stopped.

I hope this helps...

Run the highest octane you can find in your next fill up (anything 91-94 octane).

Get yourself a can of "Marvel Mystery Oil" (AKA trans fluid) and put it in with your next oil change to unstick any lash adjusters.

If the knock persists, it's something major and it doesn't matter if it's a rod, piston, or timing chain tensioner... if it's any of those, the engine will die a sudden and horrific death when it's least convenient for all... Like mine did... at Spring Zing 01... $683 and several hundred miles on a flatbad U-haul later I had my car home to Iowa... Then, I got to put a new engine in it.

Although I ended up with the first 3 Liter '98+ SE, I would have rather gone about it in a different way.