Yes. Don't disconnect it when running - you may get drenched. Not running .it returns fuel back to the tank
How To Stop Pre-Detination Rattle?
- Thread starter LFD2037
- Start date
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When running it vents the excess pressure to tank. Shut off engine -ignition off-Wait a few minutes before u disconnect and have a rag handy
I'm not sure I understood you correctly. Are you saying that when you disconnect the return line and blow in it, your not able to blow thru it and hear it going into your tank? That line is a straight shot into tank and if it's clogged there is your problem- you'll have to follow it and unclog it.
Strange... You may want to look more into this. It a quarter inch line and should have very little resistance because the regulator only bleeds off maybe 1-10 psi. I disconnected mine and it's fairly easy to blow thru - maybe it's kinked somewhere. (Also I did the canister mod so my tank would vent properly)
I used to have about 3 sec vent b4 the mod- now I don't have any venting at all when opening tank.
As far as blowing in the line I think you blew in the wrong side. You said you blew into the metal line- you need to blow into the rubber return line. The metal line on the regulator i don't believe you should blow into because it is a diaphragm. I pointed to the hose on the last ten seconds of the video I posted earlier. Anyway- 10 -15 second vent seems like forever to me. Good luck and hope you get it figured out
As far as blowing in the line I think you blew in the wrong side. You said you blew into the metal line- you need to blow into the rubber return line. The metal line on the regulator i don't believe you should blow into because it is a diaphragm. I pointed to the hose on the last ten seconds of the video I posted earlier. Anyway- 10 -15 second vent seems like forever to me. Good luck and hope you get it figured out
LFD2037
TEXAS LEXUS!
- Thread starter
- #149
I blew into the rubber line that I disconnected off the top of the regulator. That rubber line is about 3-4" long then turns into a relatively small metal line. That's the metal line I'm referring to. Since that rubber line feeds to that metal line, that's the restriction I speaking of. There was quite a thread on here about the 'venting' & it became apparent 10-15 seconds isn't that uncommon w/our rigs. Mine may be a less if I take the cap off quickly but generally I'm in no hurry.
LFD2037
TEXAS LEXUS!
- Thread starter
- #150
I'm SILL dealing w/this now that it's hot again. Didn't do it all winter long & only started doing it again once it got ~85*+ & after engine is warmed up. The more heat soaked it is the worse it is. I'm torn between it being pinging or valve rattle. Would higher temps & lower fuel octane have ANY influence on creating valve rattle? Since this started I've changed/added/checked:
3* timing
no CEL
runs 100% normal other then this situation
used Techron x2, MCCC, Redline cleaner x3, various other upper cylinder cleaners multiple times
new fuel filter/fuel pump sock/O2 sensors/air filter/oil/oil filters/EGR modulator
checked FPR
probably more stuff that I'm forgetting
ONLY improvement is 92/93 octane fuel or cooler temps.
This seems to happen every summer, but not winter, & doesn't appear to be an item that 'might be going out' as it's been doing it for several summers now.
Any new input?
3* timing
no CEL
runs 100% normal other then this situation
used Techron x2, MCCC, Redline cleaner x3, various other upper cylinder cleaners multiple times
new fuel filter/fuel pump sock/O2 sensors/air filter/oil/oil filters/EGR modulator
checked FPR
probably more stuff that I'm forgetting
ONLY improvement is 92/93 octane fuel or cooler temps.
This seems to happen every summer, but not winter, & doesn't appear to be an item that 'might be going out' as it's been doing it for several summers now.
Any new input?
I read the whole thread and don't have much to add other than I have the same problem under the same conditions. No CEL, runs great, timing set per FSM at 3*, new plugs, wires, cap, rotor, etc. Plenty of power, idles fine and averages ~15 mpg. 164k miles.
One thing I will add is that I *think* it is possible to have the distributor off one tooth and still be able to set the timing correctly because I think I've done that. I changed my distributor o-ring a while back (a year ago?) and then re-installed the distributor (I paid attention to make sure the rotor went back to #1, etc.). From an initial timing standpoint, I simply put it back to where the "clean spot" was where the bolt was before (thinking that would be close enough for me to start it up and set the timing). Well, I start it up and it runs horribly. I loosen the bolt and have to twist the distributor quite a bit to get the timing to 3*. A test drive confirmed that it ran fine, so I just shrugged my shoulders and drove it.
I figured there was no way in the world it could be off one tooth and still have enough adjustment in it to bring it back to spec. Reading this thread, I think I have it off one tooth. I might check this out (and fix it if need be) and then see if the rattle goes away...
One thing I will add is that I *think* it is possible to have the distributor off one tooth and still be able to set the timing correctly because I think I've done that. I changed my distributor o-ring a while back (a year ago?) and then re-installed the distributor (I paid attention to make sure the rotor went back to #1, etc.). From an initial timing standpoint, I simply put it back to where the "clean spot" was where the bolt was before (thinking that would be close enough for me to start it up and set the timing). Well, I start it up and it runs horribly. I loosen the bolt and have to twist the distributor quite a bit to get the timing to 3*. A test drive confirmed that it ran fine, so I just shrugged my shoulders and drove it.
I figured there was no way in the world it could be off one tooth and still have enough adjustment in it to bring it back to spec. Reading this thread, I think I have it off one tooth. I might check this out (and fix it if need be) and then see if the rattle goes away...
It will NOT time ok with a tooth off unless its like an old domestic with a hold down that allows full rotation of dist. "Tooth off" on a distributor just requires you to turn it further that direction. The spark is in relation of the shaft and rotor to the housing.
LFD2037
TEXAS LEXUS!
- Thread starter
- #154
I took multiple pic's of my distributor & rotor position prior to removal & it went back in looking just like the pics so I really doubt that's my issue. That is unless off by 1 tooth could be the rotor being only 1/3 of an inch off, or less, than what it was prior to pulling the dizzy.
Well, that was my assumption until I read this thread. My intent has been to go back and do it over again, but it runs just fine so I haven't been in a big hurry. IIRC the distributor drive gear doesn't have a lot of teeth on it. 360 degrees divided by the number of teeth is a much larger number of degrees than the small amount of adjustment available. So, I haven't worried about it.
All of my 80 series have had this issue, even one with 70K miles. My current 80 has 200K and will do it more on hotter days with the AC on, and little to near none when I add 2-4 gallons of 100 octane to 91. I think its a combination of fuel quality and the way the fuel/timing specs where set from Toyota. Drives me nuts.
LFD2037
TEXAS LEXUS!
- Thread starter
- #159
Yes I changed them when I started to think it was running lean. Could fuel octane AND heat have an effect on valve rattle? Mine won't do it in park at all, will barely (very quietly) do it by holding brake down and increasing RPM's. I have to drive it, accelerating lightly between ~1,500 and 2,000 RPM, to make it happen. There's no way for me to truly listen to it at the source.
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It only does it while under load with minimal throttle as you mentioned. I wonder if the injectors are not spraying enough fuel as needed causing the pinging? Who knows, I recently saw a newer Toyota, 2010+, and heard the same pinging while it was starting off from a red light.
