Engine Knock

hi everyone, i am brand new to this forum but am excited about it. i bought an 03 Tacoma PreRunner Double cab and i love it. it's my baby. i would get rid of my wife before i would that truck. My question is, when i first start the truck on cold mornings the engine knocks for about 3 seconds and then stops. it has never done this before, and i have had the truck going on 3 years now and it has seen alot colder weather than we have been having lately. i am shooting in the dark here but is it maybe because i have been using 5W-30 oil instead of 10W-30? Please someone help me. i'm looking forward to diving into this forum cause i am going to keep this truck for a very long time so i will need some ideas. thanks.

 

I just read a thread on here about the same issue and it was something with the air intake seal needing sealed. sounds strange, but i heard its a fix. do a search on it, maybe thats the problem

 

here u go, maybe this could help:
http://www.tacomaworld.com/forum/2nd-gen-tacomas/57893-rattling-noise-when-cold.html

 

awesome thanks for the help swise, i will try it when i get home tonight if it's not dark or first thing tomorrow.

 

Welcome to TW.

 

thanks neslerrah....i'm really excited about finding this site. i'm ready to start some upgrades but as some others $$$$ is low so i will have to start small. the biggest thing right now is to replace the LF park light from where i hit a deer several months ago. i'm grateful there was no body damage but am still bummed that there is a blemish at all on my truck.

 

Mine does the same thing. Ive given up on trying to solve it I think its internal but I realy dont know. I use 10w30 and it still knocks. Only on a cold morning ranging form about 5-15 seconds then goes away.

 

What causes the knocking in the cold morning is there is no oil in the top end from sitting over night (it slowly drains back down to the crankcase) it takes a few seconds for the oil pump to build pressure. The knocking is a little valve clatter, the hydraulic lifters that need to pump up. It probably wont hurt anything if its only for a few seconds...

if you use some lucas oil synthetic additives, it makes the oil bond to the top end better without thickening the oil. it should make some oil stay in the passages so the pump doesnt have to refill the passages but it will still need to build oil pressure. It might prevent that early morning knock.

 

someone on here directed me to another thread about the knocking coming from where the cold air intake meets the right fender. it's worth a look to see if that is what it is and if not then i will try some synthetic oil to where if it does rattle it hopefully won't be doing a great deal of damage.

 

Not to curse my engine, but mine is more of a "knock" rather than a rattle. Not like banging with a sledgehammer, but definatly not a light rattle. Ive used the lucas before but did not stop the problem.

 

thats for 2nd gens with the TRD Cold air intake. If you have a CAI check it but without hearing the noise myself it would be hard for me to tell if it was engine noise or intake rattle. have someone start your truck for you in the morning while you listen.

 

chevys are notorious for cold knocking until the parts warm up and expand. my 2500 suburban 454c.i. started doing it at 40k and now has 247k and ive never had an issue with the engine and the chevy knocks from every cold start till the engine is warm.

youll be fine just dont pound on the truck while its cold.

 

ok i understand now. yeah if i had to say, it's more of a knock than it is a rattle. and i would be a knock like you were running it out of oil. if the cold air intake thing is for later models then i would venture to say that your response above about oil needing pumped to the top end.

 

all of you have been a big help...i really appreciate it