bosco659
05-22-2007, 06:58 PM
I have developed an engine noise that I can't seem to get rid of (permanently) and am looking for suggestions. Here's what I have: '00 Runner Limited, 3.4L, S/C, Walbro fuel pump, 305cc injectors, 2 heat ranges colder plugs, 170 degree thermostat, SAFCII, automatic, 145,000 KM (90,000 miles). The supercharger has been on the truck for over half of its life already so I am not a newbie to the world of boost on this truck and its associated problems.
Here's the problem: It is an intermittent noise that seems to be coming from the passenger side of the engine. Sometimes it can be heard under minimal acceleration from 2000 to 2200 rpm and again at 3000 to 3200 rpm. Sometimes it will disappear completely and other times I will only hear it under boost (high or low).
This one has me stumped. It does not sound like pinging or pre ignition. I know what that sounds like. It sounds more like a chattering or clattering sound that almost sounds like lifter noise. But again, sometimes it will disappear for days.
Here's what I have done so far: no codes, Seafoam treatment, new plugs, new thermostat, always run 94 octane and octane booster doesn't help, all vacuum lines in good condition, cleaned MAF sensor.
Any ideas out there? Some suggest a knock sensor or a O2 sensor on their way out (not far enough to throw a code). Do the 3.4L have any history of lifter problems? Even if it was a lifter problem, whay would it be intermittent? I have trie pulling the EFI fuse to see if the noise comes or goes but it doesn't seem to make difference. I will install my wideband tomorrow to see how my AFR's are doing.
Any input would be appreciated.
Thanks
Vic
Here's the problem: It is an intermittent noise that seems to be coming from the passenger side of the engine. Sometimes it can be heard under minimal acceleration from 2000 to 2200 rpm and again at 3000 to 3200 rpm. Sometimes it will disappear completely and other times I will only hear it under boost (high or low).
This one has me stumped. It does not sound like pinging or pre ignition. I know what that sounds like. It sounds more like a chattering or clattering sound that almost sounds like lifter noise. But again, sometimes it will disappear for days.
Here's what I have done so far: no codes, Seafoam treatment, new plugs, new thermostat, always run 94 octane and octane booster doesn't help, all vacuum lines in good condition, cleaned MAF sensor.
Any ideas out there? Some suggest a knock sensor or a O2 sensor on their way out (not far enough to throw a code). Do the 3.4L have any history of lifter problems? Even if it was a lifter problem, whay would it be intermittent? I have trie pulling the EFI fuse to see if the noise comes or goes but it doesn't seem to make difference. I will install my wideband tomorrow to see how my AFR's are doing.
Any input would be appreciated.
Thanks
Vic