turbo? Knock sensor? running lean?

[SideWinderGX]

the code is 52, so looking here: http://www.cygnusx1.net/Supra/Librar...ion=FI&Page=28 gave me a Knock Sensor Signal. apparently, it could be either of the two knock sensors or the ECU. and i know theres a post around here with the knock sensor locations, i posted on it yesterday...got it. http://www.toyota-supra.info/forums/...ead.php?t=6577

im not a supra wizard, so thats all i know haha, maybe someone else will post here with more information on what it could be. thats a start though.

[west_side_supra]

what does the knock sensor do exactly? why would it cause it to feel like its looseing power or dragging behind like im towing somthing.

also i have mixed gas for the first time
Safeway gas 92 octane 1/2 Tank of gas
chevron 92 octane w/techron 1/4 tank of gas
could this be causeing the issue

and one last possible the BOV might be leaking from the IC i can feel vacume when i put my hand on the seal.

[SideWinderGX]

im not an expert, but as far as i know, this is all close to correct:

knock is the preignition of gasses in a cylinder. instead of the piston compressing the gases and having the reaction occur, they combust prematurely, backfiring, and slow the pistons down. hence, they could slow the car down if bad enough. it happens if you ahve too high of an octane in your car, or if you mix them.

although, i dont think mixing gas matters as long as its the same octane. maybe it was a bad batch from one station that messed up yoru entire system.

um, if the blow off valve is leaking, thats obvoiusly not a good thing, although im not sure how that would relate to knock or anything messing up.

[west_side_supra]

sweet deal, so im going to wait for my tank of gas to empty out and im gonna stick with my usal safeway 92octane since i know that works fine no issues, or maby ill just stick with the lowest i dont know they all work fine from safeway damn chevron . well thanks ill keep posted once i do a refill

[marc]

nope, a code 52 signlas that the wires running from ur knock sensors to the ecu has shitted out. u need to cut the wires and resolder new wires in their place. i used microphone wire becazuse its the same shielded wire.

[IHateHacks]

Marc, usually when that happens the CE light stays on as long as the engine is running.

west_side_supra said: "if i drive it normal i have no problems
when i drive it hard enough for the turbo to kick in the check engine light will turn on."

And he said "is boosting past stock so 10-11psi"

I personally think the knock sensor is doing its job, and detonation robs you of power so that would explain your "dragging behind like im towing somthing."

When the ECU detects knock, it retards the timing like a mofo and performance goes way down.

Why don't you try lowering the boost, and take a few "shims" out of your wastegate. Or put a walbro 255lph fuel pump in it. 550's wouldn't hurt either.

[west_side_supra]

well its been running fine untill a couple days ago when i mixed to diffrent gas stations. so ill still try to run outa gas and refill and try it from there if all goes wrong still ill go and see about getting a new pump. but for now im driving it nice

[ddouglas77]

Originally Posted by SideWinderGX

knock is the preignition of gasses in a cylinder. it happens if you ahve too high of an octane in your car, or if you mix them.

although, i dont think mixing gas matters as long as its the same octane. maybe it was a bad batch from one station that messed up yoru entire system.

um, if the blow off valve is leaking, thats obvoiusly not a good thing, although im not sure how that would relate to knock or anything messing up.

No, preignition happens if your octane level is too low, not high. The higher the octane, the cooler the burn, which is why it is only supposed to be used for boosted, nitro or high compression engines.
The BOV leaking under vacuum will more than likely leak under boost, which will cause a lean condition.