knock retard can't get rid of? I have a 98 t/a with long tubes and ls6 intake and small comp cam.The car has been tuned for awhile.with no problems with spark knock.The only thing I have done to the car lately is change out the ac compressor. Had the tr55 plugs in for awhile the plugs still looked brand new when I pulled them.I was getting 3 degrees of knock on my scanner and it is audible too.So I changed the plugs out to the tr6.I am still getting some knock retard on the scanner.Could the ac be getting the motor to hot?My temps are usually around 200 in the Florida heat.It all started after the ac compressor I put on.what is weird It only does it under a load.When the motor is kinda sluggish I can ease on the gas and you can hear the spark knock.I can put it to the floor and no spark knock.I am lost.It does it with the ac on are off. |
Start by checking the fuel pressure while you are driving. see where its at when it pings. |
I may have figured it out I got a pretty aggressive tune.When the temp gets to 200 I can hear spark retard audibly.I got another tune that is not as aggressive I am going to swap out computers and try that.I got to have my ac.It never gets hot till I turn the ac on.I love this tune I hate to swap it out.I need to get me a hp tuner so I can tune myself and I could take some timing out. |
last month I changed from the TR5 gapped to 55 to the TR6 gapped at 40, and my car ran 6-8 degrees hotter, and I got more KR. I tuned out the KR, but I bought another set of TR5's to put back in the car when it gets cooler in Tampa |
Originally Posted by Phil'sC5vette
(Post 13762436)
last month I changed from the TR5 gapped to 55 to the TR6 gapped at 40, and my car ran 6-8 degrees hotter, and I got more KR. I tuned out the KR, but I bought another set of TR5's to put back in the car when it gets cooler in Tampa |
You getting oil in your intake? I'm having a similar knock problem but no audible ping/knock but I found oil in the intake. I ordered a catch can but haven't installed it yet. |
I got a norris catch can and it works awesome.I was coming home today and left the a/c off and the car stayed around 190 on temp and no knock.Turned the a/c on the car got to 205 started seeing and hearing audible knock.So I guess it is just when the motor gets over 200 degrees.What would cause that?I got two computers one tune aggresive and one not.Both tunes I am getting spark knock when the motor gets over 200.I like my a/c but I am going to leave it off till I get this problem took care of.Don't want to hurt my motor. |
OP, you may want to look into a 160* T stat. Along with the change in the tune for the fans to come on sooner. |
Have the tuner turn you fans on at 170 and change you thermostat out for a 160 and then you shouldn't have the temps reach 200. Idk what my tuner made my fans come on at but my car only gets up to 197 max I have no ac though so aim not sure what it would get too with Ac and that's with the stock t stat |
add some race gas. see if it goes away. |
I am pretty sure it has a 160 in it and the fans come on early.The car hardly ever gets over 185.My old ac compressor was out when I bought it so I never got the temps high until I fixed my ac and know with the ac on in 100 degree florida weather it will get up to 210 to 215.Looks like I will just have to get rid of the a/c or get a bad radiator that flows like mad.It is hot in florida:emb::emb::emb::emb::emb:.What I can't understand it is only when I ease on the gas.If I get on the gas hard it goes right away.I will spray some seafoam in the intake tomorrow.Maybe it had some oil in there before I put my catch can on. |
Most likely becuase when you go WOT your getting into PE in the tune commanding a richer mixture. Light throttle medium load you may run into some leaner hotter temps. If I was you I could be trying to cool that thing down. Double check the T stat is working right with a pan of hot water on the stove. Check the rad. and remove the a/c if ya are up for it. Personally I like mine but whatever it takes sometimes. |
Oh and seafoam and a catch can would be a great start to. Burning that nasty ass oil does nothing except make carbon and lower the knock resistence of the fuel your burning. |
Thanx for all the help I did some seafoam.Knock still there when temp reaches over 200.I am going to work on some cooling upgrades.I have 160 thermostat already and My fans are coming on early.What kind of water are antifreeze to use which is best?I am going to try some water wetter.If I can keep it under 200 with the a/c on It will be safe.Temps here in florida is 93 with 110 humidity. |
Lugging the motor at a low rpm will cause spark knock, especially with the ac on.. With your ac condenser right below your filter, you will see alot higher iat's that can cause knock/pinging issues.. Finding a way to lower those ( FTRA, Chris1313 ram air or custom CAI) will help combat your issues.. Also down shift to avoid loading the motor. |
Originally Posted by MM98
(Post 13783021)
Lugging the motor at a low rpm will cause spark knock, especially with the ac on.. With your ac condenser right below your filter, you will see alot higher iat's that can cause knock/pinging issues.. Finding a way to lower those ( FTRA, Chris1313 ram air or custom CAI) will help combat your issues.. Also down shift to avoid loading the motor. |
Originally Posted by sabersaw30
(Post 13784357)
Wouldn't the ram air block my radiator more?I have a lid with a k&n filter.Good idea on the down shifting.Because that is the only time I am getting knock when the motor is lugging when I give it gas. |
Should the PCM show knock if the Knock sensors are disconnected. When the TPS hits 60% I'm getting 8* of knock even if I unplug the knock sensors. |
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