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Discussion Starter · #1 ·
So here it is, two days ago the supra was running perfect. With a bleeder T my car was hitting ~17-18psi and running strong. Yesterday I was testing my methanol kit and making sure everything was working before going to get a tune. After a couple short pulls of spraying just water the car would not boost over 10psi. It was also struggling to make 10psi and was jumping back and forth about 4psi while working its way up to 10psi. It was also struggling to rev over 5k with the water spraying. I thought it was because I was spraying the water and it was killing power but it did the same thing today on the way to the dyno. It was not as bad but still noticeable. I also changed my plugs this morning before I went to the dyno but that didn’t solve the problem. So I get to the dyno and the car will not go above 10psi and my dyno graph looks like a flight of stairs. I was running an open wastegate on the dyno and I usually hit ~23psi this way. I did a boost leak test and I have no leaks. Then I thought it was my motor but it runs normal in vacuum and when I rev it up in neutral it doesn’t miss a beat. As soon as it starts to get into any boost my boost gauge starts jumping back and forth. It feels like the wastegate is opening then shutting over and over again. It also makes a sound like the wastegate is opening and shutting or the bov is opening then shutting. Obviously the water messed something up but what could it have done? One theory was that the water cleaned some carbon from the motor and it scored up the turbo housings and messed up the blades. Another was that the water screwed up a sensor but if it did which one? If anyone has any ideas of what happened or what is going on I would really like to hear them.

Setup:
stock twins
DP
HKS TI
TRD single Disk
Greddy 3row
Dereks meth kit: standard flow, M10 nozzle

Thanks
Buddy
 

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Sounds like you're spraying too much H20. Back it off a little and see what the results are. Whenever you introduce a new liquid you ALWAYS want to start off low and work your way up. You might also try spraying 100% methanol instead of H20 and see if that changes things.
 

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Discussion Starter · #3 ·
I turned off the injection and it still runs horrible. Not as bad as when the water was spraying but still really bad.
 

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Does the engine seem to be misfiring, or is just the boost irratic? Where were you injecting? Check the intercooler for water. Any pics of you setup?
 

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take the meth nozzle out completely and see if that solves your problem... its possible that the nozzle is leaking and shooting way too much meth when u want it, and leaking when you dont want it to

where were u spraying the meth? its possible it hurt a sensor (for example you shot way too much meth and it got into your MAP sensor, or FPR etc)

i say, when something doesnt run right after installing something, remove it completely to make sure thats whats causing the problem

also change ur plugs, do an oil change, and put a new tank of gas in
 

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Discussion Starter · #7 ·
I have had the methanol kit on the car for a while. I just had not used it because my car was not tuned for it. When I first installed it everything worked perfectly and it still does. I put new plugs in the morning after the car was not running right so that wasn’t the problem.

The car now revs up fine it just does not build the boost it should. If you rev the car up a little in neutral you can hear a rattling noise coming from the turbos when the rpm is coming back down. I thought my exhaust was rattling but it is definitely coming from one or both of the turbos.

Rotorytoy: It could have a slight misfire but the boost is definitely erratic. You can feel it start to build boost then drop over and over as it goes through the rpm range. I am going to do a compression test and lower the gap in the plugs a little and go from there.
 
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