Thread: Engine rattle please help new guy.

I have a 04 GP GT. When i first start the car in the mornings or after it has cooled down it has a ticking sound untill it has warmed up and it goes away. My biggest problem is when its under a load, usually 1/2 throttle , it has what sounds like some very bad spark knock and it even has less power when it does it. I have searched and came up with one thread but he was having slightly diff problem than me. I have tried diff octanes and fuel additives to try and fix the issue but nothing works. I wonder if it is just really bad spark knock or is it something else such as bad timing chain etc... I have heard spark knock before on other cars but this is really bad. Any help would be greatly appreciated.

Yeah i have changed plugs and wires and have even tried that Seafoam. Funny thing is that 9 out of 10 times when i go WOT it doesnt rattle at all. its got me stumped. I used to have a 02 GP GT and never had this issue. No SES lights either.

How many miles? Could need a timing chain tensioner.

It's completely stock and has almost 98000 miles.

What brand/type of plugs did you install? If they are platinum or double plats then get them out and get some copper ones in there. These motors do not like plats at all.

Have you cleaned the TB? MAF?

I just put regular copper back in , no platinum. No I haven't cleaned the TB or MAF. Is there any specific cleaner I should use on them. And is there any tips on cleaning them so I don't screw anything up.

You can clean the TB with brake cleaner. To clean the MAF use only MAF approved cleaner. I know its like $7 a can but it won't harm your $150 sensor. The backside (the side that you can't see) of the TB butterfly gets carboned up and can stick open a bit causing wierd stuff.

Good call on the coppers.

Does kinda sound like an exhaust leak. They usually seal up once everything gets hot. I've had one at the rear mani. on my 00 GT for a while now that I need to take care of.

Don't know about the timing chain tensioner. Haven't done that one yet. I do know that the chains themselves last quite a while though.

Thanks I will give that a try. I'm installing my shift kit this coming weekend and might as well do that too since i will be under the hood anyway.