Eastcoastrunner
New member
mine does it all the time, even when engine warm. hate it
I know he did, but if that doesn't fix it for whatever reanson then I am out big money. I wish he would come back online and re-evaluate. I think he's only posted on the forum once.
4RunnERD,
I have 07 v8 Limited and apparentely, I have the same kind of noise at start up and starting driving when engine is cold. I just live with it as I new it was going to be a PITA to diagnose something like this. But it annoys me a lot. I follow this thread very close and really appretiate all your affords to bring the truth up to light.
Please, keep everybody updated on this matter.
mine does it all the time, even when engine warm. hate it
I find the fuel pump idea to be a bit of a stretch, the fuel pump is located inside of the fuel tank. If it was some how causing a knock/ticking noise it would be closer to the fuel tank than under the hood. In my personal opinion its more of a long shot.
Something just popped into my head as I was working on some cars at the dealership. A lot of people notice that Toyota engines have a noticable "Tick" caused by the fuel injectors and how often quiet the engines are.
Did the dealership check all the fuel injectors? Perhaps one is beginning to fail and is ticking louder when cold, but once warmed up, it does not sound as harsh?
Its a longshot, but I figured it's worth mentioning.
That is part of the VSV control vavle for the EVAP system.
You are still under powertrain warranty. Take it to your nearest dealer and have them keep it overnight and do a cold start. Piston slap engines will slap when it is 90 degrees out as the pisotns expand to tolerance when warmed up which is 165-200F depending on the engine. If the dealer does determine it is a piston slap issue then request a rebuild from Toyota. You might get it. If it is the fuel pump I would still complain to Toyota and you may get it under goodwill.
i mentioned the tick sounds mine makes (similar to yours) to a mechanic friend, ...first thing he said asked was if there was an exhaust manifold leak starting...
Would exhaust manifold be more when hot or cold though?
.....
Okay so I really tried to pay attention to where this noise was originating from and it sounds like (I could be wrong) that it starts near the fuel tank or underneath me and very quickly travels up to the firewall/engine bay area where it becomes more prominent and audible. I am starting to wonder if there is some kind of air bubble or vaccum issue that needs to be overcome by moving fluids or built up pressure on cold start ups.
On that note does anyone know what the part circled in red is? It has lines that run from one end to the top of the throttle body, and the other end appears to run back down the firewall and under the truck with the fuel lines. I pulled it out and it appears empty and hollow inside. I can see straight through it and when I shake it, it does not make any noise.
Are there any techs out there know that know the fuel system really well... fuel lines, vaccum hose, dampeners, regulators, etc.????
Thanks. Yeah I figured out the Maintenance light thing. I think the dealer I bought it from, a Ford delear, did the mandatory oil change when they took it in on trade even though it probably wasn't needed timeline wise yet from when the previous owner last reset it. There are only a 1,000 miles on it since the oil change so the light probably wasn't on and probably not reset at the Ford dealer.
In terms of noise what other specifics do you need to diagnose it...
-does every morning now (up from only on cold days) was 82 today.
-deep knocking eventually turning into a droning noise.
-if left to idle still makes noises once fully warm 10 minutes plus
-only goes away after driving
-putting it in and out of gear and thus putting a slight strain on the engine will make the noise come and go briefly, but noise reappears and remains until driving for a while.
- really starts out as a knock and then the drone that comes sounds like something rolling around or rattling in the engine or engine bay, then knock comes back for a few seconds, then back to drone, and back and forth until driving for a while.
EDIT: I am using the word knock, because it doesn't sound like a other more metallic or pingy or disiel sounding piston slaps videos that I have seening on you tube.