Need more detailed info.
When does it knock (rpm's, speed, etc...)?
When does it knock (rpm's, speed, etc...)?
not a hot rod question but i still need engine help
my nephews sunfire 2.4 litre twin cam . has a knocking noise, it just started all of a sudden, motor is not as fast as it was .
my question is , is there something that goes regularly with these motors/??i'm thinking cam but am unsure. the older cavaliers had valve trane problems, it's a 97 and well worth fixing as it has only 115,000 k.m.
my question is , is there something that goes regularly with these motors/??i'm thinking cam but am unsure. the older cavaliers had valve trane problems, it's a 97 and well worth fixing as it has only 115,000 k.m.
1 - 14 of 14 Posts
It's pretty common for the timing chain tensioner to wear down on the 2.4s and then the chain will slap quite badly. This could be the problem you are encountering.
Of course, you will need to actually diagnose the problem rather than guess at it. If it's a rod or piston noise, it should be obviously different from a timing chain slap.
Of course, you will need to actually diagnose the problem rather than guess at it. If it's a rod or piston noise, it should be obviously different from a timing chain slap.
it knocks at all rpms relatiive to engine speed.it's bordering on loud but not quite,the vehicle starts and runs like normal. i think it may have toasted a bearing or the like since the performance suffered little(doesn't seem like a bad cam.
i was just hoping someone has had some experience with this motor and it was a common problem like the dodge minivan transmission lock up converters failing or the like.
maybe a g.m. mechanic will read this or something. thanks guys, mike
i was just hoping someone has had some experience with this motor and it was a common problem like the dodge minivan transmission lock up converters failing or the like.
maybe a g.m. mechanic will read this or something. thanks guys, mike
similar stuff
my girlfriend had a 90 grandprix with the same problem and diddling with the car after she bought a new one i realized that the oil return hoses were shot,creating a very loud knock at all rpm,especially in the top end where the oil wasent. So i replaced them with hydraulic grade hose and it still has a very very quiet knock but that seemed to have fixed it.
Did you change any plugs or anything latley? Our problem seemed to have been caused be extreem heat from platnum 2's we had installed, but i dont know that forsure all i know is it just started getting a loud knock and then louder....
my girlfriend had a 90 grandprix (2.3L quad 4) with the same problem. i was diddling with the car after she bought a new one, i realized that the oil return hoses were shot,creating a very loud knock at all rpm especially in the top end where the oil wasent. So i replaced them with hydraulic grade hose and it still has a very very quiet knock but that seemed to have fixed it.
Did you change any plugs or anything latley? Our problem seemed to have been caused be extreem heat from platnum 2's we had installed, but i dont know that forsure all i know is it just started getting a loud knock and then louder....
my girlfriend had a 90 grandprix (2.3L quad 4) with the same problem. i was diddling with the car after she bought a new one, i realized that the oil return hoses were shot,creating a very loud knock at all rpm especially in the top end where the oil wasent. So i replaced them with hydraulic grade hose and it still has a very very quiet knock but that seemed to have fixed it.
Did you change any plugs or anything latley? Our problem seemed to have been caused be extreem heat from platnum 2's we had installed, but i dont know that forsure all i know is it just started getting a loud knock and then louder....
my girlfriend had a 90 grandprix with the same problem and diddling with the car after she bought a new one i realized that the oil return hoses were shot,creating a very loud knock at all rpm,especially in the top end where the oil wasent. So i replaced them with hydraulic grade hose and it still has a very very quiet knock but that seemed to have fixed it.
Did you change any plugs or anything latley? Our problem seemed to have been caused be extreem heat from platnum 2's we had installed, but i dont know that forsure all i know is it just started getting a loud knock and then louder....
my girlfriend had a 90 grandprix (2.3L quad 4) with the same problem. i was diddling with the car after she bought a new one, i realized that the oil return hoses were shot,creating a very loud knock at all rpm especially in the top end where the oil wasent. So i replaced them with hydraulic grade hose and it still has a very very quiet knock but that seemed to have fixed it.
Did you change any plugs or anything latley? Our problem seemed to have been caused be extreem heat from platnum 2's we had installed, but i dont know that forsure all i know is it just started getting a loud knock and then louder....
my girlfriend had a 90 grandprix (2.3L quad 4) with the same problem. i was diddling with the car after she bought a new one, i realized that the oil return hoses were shot,creating a very loud knock at all rpm especially in the top end where the oil wasent. So i replaced them with hydraulic grade hose and it still has a very very quiet knock but that seemed to have fixed it.
Did you change any plugs or anything latley? Our problem seemed to have been caused be extreem heat from platnum 2's we had installed, but i dont know that forsure all i know is it just started getting a loud knock and then louder....
Engine noise
Sound like a problem in the timing chain or tensioner. Either one is an exciting job. About the right milage on the 2.4 for this.
Sound like a problem in the timing chain or tensioner. Either one is an exciting job. About the right milage on the 2.4 for this.
also check compression, and oil for coolant contamination. 2.3 & 2.4 quad4's were famous for cracked heads. they also had an erosion problem in the fire ring area of the cyl head.
so the general consensus seems to indicate valve trane,it seemed like a top end knock to me but i'm a better parts changer than a mechanic.where are the oil return lines??di i have to strip the engine down to check the timing chain tensioner??glad to hear it's a chain and not a belt.
keep it coming, mike.
keep it coming, mike.
Engine noise
I have not done a Quad 4 engine Timing Chain since 95. But unless somethings changed on 97 & up you are going to need a special timing chain tool kit made for the quad 4 engines. Kent-Moore used to make the kit. For a while it was an specilized tool available to GM dealers. It is a major job to change and put back in time. The chain used to be long enough to be a spare if you owned a Harley and then some! Another vehicle designed by GM to be repaired by the dealership.
I have not done a Quad 4 engine Timing Chain since 95. But unless somethings changed on 97 & up you are going to need a special timing chain tool kit made for the quad 4 engines. Kent-Moore used to make the kit. For a while it was an specilized tool available to GM dealers. It is a major job to change and put back in time. The chain used to be long enough to be a spare if you owned a Harley and then some! Another vehicle designed by GM to be repaired by the dealership.
we'll have to tear it down , we were going to take the engine out and bring it to a shop but we may just break it down in the car and see what has to be done . i think now we can be sure of it being in the top end.
thanks guys for all the imput.
p.s. i'm still holding out for the g.m. tech who fixes this problem twice a week or something but i won't hold my breath.
thanks guys for all the imput.
p.s. i'm still holding out for the g.m. tech who fixes this problem twice a week or something but i won't hold my breath.
is the noise a top end knock or a sort of rattle knock ???
on a 350 it would sound like a bent pushrod or rocker arm. this has neither. now i know why i like the oldies...mike
Start it up, be sure it is knocking...then with the engine running pull spark plug wires one at a time (I mean to pull one off the plug, listen, then put it back on). If you pull one off and the knock is either a lot less noticible or it is gone let us know.
i'll check it out the weekend and let you know.thanks
1 - 14 of 14 Posts
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