Cold Engine Start (/w Knock)

[underoathfan14]

my 5.3 does it during the winter months. sometimes during summer if it hasn't been ran in 3-4 days.

sounds like a damn diesel!

[rompn4x]

My buddies' 3.4L Grand Am makes all sorts of clicking noises before it warms up. Afterwards it runs like a champ.

[KiroTheGreat]

Yea those engine types are known for their high mileage piston slap.

[Mymothersson31]

Piston slap. Almost all GM 3.1 and 3.4 V6 engines do it. Design flaw. My 97 LTZ 3.1 with 158k does it every morning. After it warms up the slap goes away and the engine is quiet. I just wait until the noise subsides then take it easy for a couple of minutes while the engine warms up. No problems and still on original engine.

[seapeddler]

A 'preluber' would prevent all of these problems with complex OHC rocker arm engines. It takes a while for oil to get to the rockers. But, with the VW Rabbit engines, a smidge of oil stays on top of the shim/bucket assembly all night long.

Makes one wonder why Ford Triton engines have roller cam followers instead of Ferrari/Volks style shim/bucket. I like to buy something because it is good, not because it is a 'make work' project. Which Ford seems to be.

[TheMrhellrazer]

that is just ur lifters it is fine all of them do it i got a 3.8 and it does it now if ur car is at running temp and it sounds hored then there is something wrong

[kristopher3637]

try looking at the fuse for your o2 sensor, the o2 sensor determines how rich your gas fuel mixture

[discretesignalz]

Piston slap. 3.1L (M) and 3.4L. GM messed up when they engineered the pistons. The noise goes away or lessens as the engine heats up because the pistons swell and take up the excessive clearance. Unless the noise was apparent when the engine was warmed up or excessively loud on a cold engine GM claims it won't effect the life of the engine. See TSB 01-06-01-005

[jordy19892012]

I have a 1989 Ford Taurus with the Vulcan, and it does this when its cold, and goes away when it warms up a little bit, but when its been driven for a while, the knock noise comes back, only instead of it sounding like 1 or 2 cylinders when its cold, it sounds like 3 or 4 when its been driven for a while. And its not a knock, but more like 3 or 4 ticks. I thought it was a rattling pulley, but it wasn't that.

[dunn98632]

I probly would not worry till it does it while warm or cold if it ever does kinda typical of this engine.

[1YODPHILLY]

My 98 SILHOUETTE Does it and quiet up after its warm but its still kind of there when i drive could someone help me thanks.

[cleven269]

Same here My 98 olds does the same thing. Just learned to live with it. :(

[luciffer420]

Its called lifter slap. the 3100 engins from gm were known for this even brand new off the lot. just a flaw.

[hellfiremusic2]

Its not pre-lubing, i have a 1995 Isuzu Trooper W/3.2 and it knocks for a little bit but not as long as yours.

[rrbigdan1]

@hellfiremusic2 dude with the Isuzu, your tentioner pully is bad. Go to Honda and get on for a Pathfinder and replace it, one bolt, realy easy, $40...

[popplewort333]

The problem is not pre-lubing the engine.

An engine pre-luber will easily double engine life. Most of the newer cars have crank-driven oil pumps. Pushrod camshafts get a supply of oil quicker, and are better engines.

Sometimes cranking for six seconds or so gets the oil gallery primed, and when it starts it will start quiet. Don't take my word for, it I may be a Pherengi spy.

[jordanhall91]

sometimes they just do that when it's cold.

[bucks2743]

piston slap

[erat91]

This.

[orrin4]

yea i have a saturn 93 and it knocks like that too.

[Kpeters]

I have a 1981 BMW 320 with a 1986 2.7 cylinder engine and it makes thay exact sound. It does shut up when it warm. Wristpin maybe? Or some sort of problem on the head? What have you found out?

[Servo888]

Didn't keep the car long enough to find out. I picked up an '08 VW Rabbit a year and a half ago, and never looked back.

[Kpeters]

Ah ok man ty :)

[Canadiank8erBoy]

Due to the engine having too much aluminum it constricts when cold causing knocking sound

[Toxichazard13]

Today my 99 escort made some sh*** noise like that for about 3 seconds and then it went away. I hope it's not a knock. the noise doesn't persist when it's warm so it leads me to believe it's something else.

[slowscort]

my car does this about a second after it starts up i think it just has to build up oil pressure in the engine the 3.1 chevy motors usually dont last that long you will be lucky to get 200 thousand out of it

[dunn98632]

some of the newer cars are pissy this way don't worry about

[Blown75]

I have a 3.4 makes sound on warm up it started after a bad tank of gas that was 50% water and rust I had to drain tank change fuel filter replace plugs and changed wires.

The noise sounds like clogged injectors to me I am still working on mine today going to start car up give injectors a tap to see if I can clear them, reason it seems to go away is that in start up the fuel pressure regulator gets up to pressure then pushes some fuel through when cold no fuel is getting through

good luck

[urbanmuscle21]

3.1L Chevy Engine ? thats Normal for those dont worrie about it

[importhater56401]

Nothing to worry about at all.

Typical piston slap.

Mine ticks 20x worse than that, and that's the last thing I'm concerned about LOL.

[ajdehler]

sounds like rocker arms. take off the valve cover and tighten the bolts. if it still does it you might have lifter problems. if its an older car with high miles the camshaft lobes might be warn where they meet with the lifters

[NRP1991]

sounds like your reeds are messed up or maybe its just a stuck needle jet. heck who knows could be a good ol sticky lifter just add some pennies inbetween the pushrod and the rocker LMFAO

[Low3LL]

i just started getting that sound..and plus my belts squeak too ... but brand new alternator belt and brand new A/c belt...and i had to remove my timing belt bcuz i messed up replacing my harmonic balancer..had to remove n reinstall my timing belt...so yeah thats how the sound occured

[stettler11]

exhaust leak small one or valves need too elongate

[infinity3jif]

thats a piston slap nothing to worry about mines been doin that for years I have a 1997 Lumina just hit 200'000 miles and the plastic radiator blew

[viperrrr6]

i assume that goes away after warmup my 92 5.7 roadmaster has the same thing, use the correct oil, and possibly check your oil pump, the 3100 and 38 series dont supply enough oil to the valves and causing that sound, other wise its normal these motors do this from new its not uncommon

[from212]

your engine is fine, it just sounds like a rough idle

[itstheiceman]

all you people saying its a crank problem or w/e are nutsacks. the engine sounds 100% fine. good ol piston slap.

[Str8Up254]

same exact thing happens with my 97 Chevy Venture that has 210k miles on it.. never had any problems though..

[dalejowen]

That sounds like it's just injectors to me. They do that on my car til it's warm

[themanytoys15]

USE SEAFOAM AND THEN CHANGE YOUR OIL WITH 10w-40 AND ADD ENGINE RESTORER AND IT SHOULD SHUT UP!!! it worked for my grand am, shes super quite now!! nooo "TICK" "TICK" "TICK" sound.

[redrider4life91]

what is seafoam?

[cbileske]

dont use those additives, they dont do any good to a engine. good chance if it is a worn out bearing or anything in the bottom end, once it is flushed out the sludge holding it together will be gone. Once this happens the tolerence's will be way out and the engine will possibly blow or burn alot of oil. Happens all the time

[popplewort333]

@cbileske

hi. I've tried Lucas oil treatment in my engine and I feel it makes an engine run smoother, It raises the flash point of any oil. This is not as good as an oil cooler though. Just to say that Lucas works.

If you don't agree that's fine. Maybe you're right.

[hellraiserryan]

wait till she blows a lower intake and 80,0000 kms later it gets crank knock

[93grandamgt]

sounds to me like a good running motor.3100 always have some sort of knock just how they were made.also change the oil pump if you get a knock could be having a weak oil pump.

[MaJixGAGT]

i have a 3.1 in a 98 grand am and i have the same knocking and it just started when i was driving down the road. odds are it is a crank shaft problem and the engine has to be rebuilt

to repace the shaft and the bearings and the arm as well. you can have someone do it for about 3000 with parts but i think i will do it myself and spend 60hrs doing it. Have fun all i will post a video of it in a coupple of months

[roflcookies]

my 94 buick century does that too but once its warmed up its fine

[kwg2005]

it's normal on the 3100. it's valve-train noise. my grand am had it, the engine had 251k on it when i got rid of the car, never was a problem.

[joshg678]

haha, you should her the noise my friends Mercedes with the desiael and 320k miles on it sounds like at start up when its less then 10 degrees outside. I swear its gonna blow, but it just won't.

[Sicj]

lol our cars intake manifold gaskets went bad our coolant got low twice but i kept it filled... we had a leak go fig. =( i use the dexcool i know it has some problems but thats what they tell us to use... they say to flush every 100,000 but i say flush half that or even less. Those manifold gaskets made a very loud clicking ticking sound that accelerated with more rpm. We also got bad gas from Casey's General Store.. we went to them for 1 st8t year then our fuel pump goes out at 40k on our car.

[KDAY24]

Get rid of DexCool, and use a universal anti-freeze!!

[MarineCore48154]

Its piston slap. just let in run for a min. when it is cold out the piston shrinks,so it is smaller than the cyinder. when the engine heats up the piston heats up and gets bigger and does not his the cylinder walls. Just let it warm up

[str8updesi]

my montero does the same just make sure oil is always filled....after i've been doing that it hasnt knocked ever since....if that does happen time for a new car

[kawasakiracer2005]

its caused by oil during warm to hot day a engine requires a certain weight engine oil than winter(colder day) warmer days cars need its requiered higher weight oil colder days a car needs its lower weight oil such information can be found in your owners manuel

[Sicj]

ugh my girlfriends got a 2003 3.1v6 chevy malibu and it sounds just like that right now. its cold as hell outside. I heard and read that thats a "Piston Slap"? maybe not? either way its annoying as hell gotta trade that junk in soon.... its around 80k miles now. We didnt hear it until around ohhhh 50k now it just gets louder and louder.. guess we better give the car a couple minutes to warm up.

[Servo888]

Car ran well till the day I sold her... Have no regrets what so ever :-) . Not the most exciting car to drive, but it got me from point A to point B, cheaply and safely.

[thingk89]

You can hear the slap going away as it warms up

[KRISTRIP14]

my 2006 pontiac montana sv6 does the samething when it's cold out it has the 3500 v6 engine in it

[ThirdeYe1337]

Just typical GM piston slap, it's not engine knocking. My mom has a 3.1 with the same issues. It runs and drives great when warm, we just take it easy until it warms up and we give it about 30 seconds to a minute to warm up a little every single time before we drive it.

[cartercl]

All of what you have heard is bullshit. It's piston slap. I have a silverado 99 with a 5.3 liter and it does it almost everyday. It's not a big deal as long as you let the engine warm up until you don't hear the knock any more. The skirts on the pistons are too short and they knock until the piston warms up and expands. It is a flaw...but not a major one. An engine can survive thousands of miles with the knock.

It's just common..and I wouldn't worry about it.

[7477238]

Never heard a Gm car do this but I do know about piston slapping. Epsecialy in the 03 olds aurora 3.5 v6 engine.

[slowregal]

Check to make sure your coolant hasn't been mixing with the oil. Does the knocking change with temperature or oil viscosity? Miles?

[Servo888]

Yup - I have every intension of driving the car into the ground. The car is worth about 500-750 dollars -- and the engine is not the biggest problem =\ . I'm just waiting for a good deal on a new car before getting rid of this one.

[materiarecordsuk]

Doesn't matter Rover drivers are used to it...... whoops did I just say that.......

[kcro25]

Lifter tap, GM cars are notorious for this.

[pezplaya]

aww look how cute u look getting into that car ;p

[Servo888]

I'm going to ignore that comment ;-)

[mustange550]

@pezplaya LOL