weird pinging issues...need help.
#31
#32
#33
fuel pressure and plenum were both checked by a tech when he replaced the freeze plug as I had mentioned the pinging. Fuel pressure was 52 PSI and holding steady.
Also, wouldn't a blown plenum = vac leak?
I have an O2 sim in the rear.
Fuel rails have been wrapped with thermo-tech for over a year. Don't currently have a cooler, but I'm trying to figure out why it would be pinging before I add one.
Freshly reset PCM or driven on doesn't seem to matter. Cold truck won't ping, hot truck will.
Timing chain was set straight up when I replaced last spring. I did mod the crank sensor but returned it to stock position when I got the SCT because I knew the timing would be aggressive.
EDIT FOR UPDATE: I do have bubbles from the rad fill port when the engine is hot. Blown head gasket? Oil is not contaminated with coolant.
Also, wouldn't a blown plenum = vac leak?
I have an O2 sim in the rear.
Fuel rails have been wrapped with thermo-tech for over a year. Don't currently have a cooler, but I'm trying to figure out why it would be pinging before I add one.
Freshly reset PCM or driven on doesn't seem to matter. Cold truck won't ping, hot truck will.
Timing chain was set straight up when I replaced last spring. I did mod the crank sensor but returned it to stock position when I got the SCT because I knew the timing would be aggressive.
EDIT FOR UPDATE: I do have bubbles from the rad fill port when the engine is hot. Blown head gasket? Oil is not contaminated with coolant.
Last edited by aim4squirrels; 11-16-2008 at 05:05 PM.
#34
SON OF A FEMALE DOG!!!!
It's the damn Plenum AGAIN! Vaughan and Steve got me 2nd guessing myself again and I went out an bought a mirror on a stick and sure as the days are getting shorter, The plenum is blown.
This will be no less than the 3rd time I have repaired this stupid thing. I have tried the hughes gasket and felpro gasket (the one with the blue line thru it), and both have failed.
Can anybody recommend a good gasket? I'm seriously thinking of having this puppy welded shut.
It's the damn Plenum AGAIN! Vaughan and Steve got me 2nd guessing myself again and I went out an bought a mirror on a stick and sure as the days are getting shorter, The plenum is blown.
This will be no less than the 3rd time I have repaired this stupid thing. I have tried the hughes gasket and felpro gasket (the one with the blue line thru it), and both have failed.
Can anybody recommend a good gasket? I'm seriously thinking of having this puppy welded shut.
#35
Just thinking out loud, but do you really think the injectors would fail when hot, if they perform fine all the other time? Im by far not an engine expert, but I would think your injectors are fine. I know you re-did your plenum.... is there a chance it went again for some odd reason? If you just said above that you get no ping with the 87 tune, but your prb still running high octane, .... plenum?
#40
I looked around and am not comming up with much. I ran across the article steve made (which is lacking pic's btw). I looked a few other places. One guy said he had luck with the "right stuff" for 45,000 with no problems yet. Honestly im surprised the fel-pro gasket didn't hold up. You mentioned about welding it and quite frankly if you had the resources to do it, go ahead. That will be easy to check for leaks too outside of your truck so your 110% sure its sealed before you drop her in. There's been talk of doing that before, but I don't think anyone has done it. Lead the way "Hanging-maw"