turbo? Knock sensor? running lean?

[west_side_supra]

ok well ill start off by mentioning what modifications i have done

Shimmed the wastgate 4 washers
lightweight flywheel
Stage 3 clutch
muffler
New spark plugs/wires

Now for the Diagnostic's results
it flashes 5 times then a pause then flashes 2 times

what is happening
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. There are no noises and i dont smell any burning. the exhaust smells fine at least rich. but it does feel like its running lean possibly it feels like theres a low response to throttle like a lag or its holding back from power.

the car drives fine even with the light on. it still is boosting past stock so 10-11psi im lost

what i think it might be
from codes knock sensor? Oxygen sensor? lean sensor?

what you guys think

[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.

[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.

[west_side_supra]

ok well ive put more gas in, and it was running fine for about 3 days then i pushed it hard and long and the check engine light came back on, did that slow down thing almost as if the clutch was slipping. but thats definatly not the case. so i went around asking my local shops and car peoples what they think it may be this is what i have gotten so far

1.Injectors
2.Fuel filter
3.Accordian hose (inlet pipe for turbo that ugly rubber thingy)
4.timing
5.CAT
6.oxegen sensor <that didnt make sense to me because if it was that the case then the light would be on all the time

[IHateHacks]

I'm telling you, you are running too much boost.

You can rule out 80% of what this "shop" told you.

You can check the resistance of the fuel injectors, 1.8-3.4 ohms for turbo models, but I already have the feeling you need bigger ones, and a bigger fuel pump running that much boost.

You should have replaced the fuel filter before you even started driving this vehicle so if you haven't yet, do it.

Accordian hose? Take it off and check for cracks. Better yet, check ALL vacuum hoses for cracks, i.e. ISC hose, PCV hoses, etc.

Like the fuel filter you should have set base ignition timing before you registered this vehicle.

You can test the O2 sensor voltage feedback. Connect a voltmeter to terminals Vf and E1 of the check connector. Voltage should fluctuate 8 times every 10 seconds.

And the cat, well you will have to take it off and look at it to see if its melted.

Or you can turn down the boost and see if thats the problem.

"did that slow down thing"- yeah thats the ecu retarding the timing, like I told you before.

[new288sup]

Originally Posted by IHateHacks

I'm telling you, you are running too much boost.

You can rule out 80% of what this "shop" told you.

You can check the resistance of the fuel injectors, 1.8-3.4 ohms for turbo models, but I already have the feeling you need bigger ones, and a bigger fuel pump running that much boost.

You should have replaced the fuel filter before you even started driving this vehicle so if you haven't yet, do it.

Accordian hose? Take it off and check for cracks. Better yet, check ALL vacuum hoses for cracks, i.e. ISC hose, PCV hoses, etc.

Like the fuel filter you should have set base ignition timing before you registered this vehicle.

You can test the O2 sensor voltage feedback. Connect a voltmeter to terminals Vf and E1 of the check connector. Voltage should fluctuate 8 times every 10 seconds.

And the cat, well you will have to take it off and look at it to see if its melted.

Or you can turn down the boost and see if thats the problem.

"did that slow down thing"- yeah thats the ecu retarding the timing, like I told you before.

Alright, Knock sensors Detect ANY knock, Rod, crank, or cylinder (pre ignition/detonation) running to lean (not enough fuel) causes Detonation which is basicly the fuel igniting before it is supposed to Because the piston/cylinder walls are TOO hot. Pre ignition is similar but it is normally caused by carbon/deposits on the intake valves getting hot and falling into the combustion chambers and could also cause (if hot enough) the intake valves to ignight the fuel on the way in.....RICHER IS better on boosted engines. anything more then 12ish pounds on stock fuel system is asking for trouble. In my humble opion replace your fuel pump, and regulator first.
the more pressure/flow you can give your injectors, the less the injectors have to work for the same amount of fuel....
Also Look up "top tier" fuels in your area, and try to stick with them.

If you are still having issues, then its not your fuel. ITs an engine knock.
Could mean 2 things, Wear on your bearings from too much boost and not enough oil pressure, or just not enough oil pressure for the boost you are running (pumps create FLOW NOT PRESSURE) (resistance to flow creates Pressure).....there is a thread im still looking for on here that mentions replacing the pump spring in the factory oil pump with one from a SB chevy, im still looking for the exact details.

Now keep in mind i am build a 600HP 7m, Using MsEfi, and a few other tricks... no, its not done yet, but if the math works out, i can make it 600 and a daily driver
Nick