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Discussion Starter · #1 ·
Was doing fine all night. Hit the speed limiter (142-143ish)and the car started acting funny. I slowed down to 60 and gas was feeling funny. I'm using the map-ecu 1 with p and p harness. Car did fine for 2-3 weeks. Dyno and all. I checked my catch can and it was filled with per fuel. I manage to get the car close to home and found this....how I made it as far as I did(45+miles), I will never know.



 

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looks like it was merely a bad capacitor that blew.
 

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Discussion Starter · #3 ·
Bad capacitor. Do you think it was pushed to hard? What made it go bad, or is this a bite from the "bad luck chuck"?
 

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What you are holding looks to be more of a voltage regulator or something of that nature. Can you read any numbers off of it still?
 

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That's not a capacitor. It's a MOSFET. Basically a high power transistor most likely used to drive the injectors(since I see a group of 6 there). It's possible that IF you upgraded the injectors..some of the wires may of shorted out due to bad wiring. Looks like one of those is seriously shot so you were probably running on 5 cylinders...hence why the car felt funny. Bad wiring or bad insulation can take a while to manifest itself. It might run perfect for a few weeks, but give it enough time with engine/road vibration and it will come loose. That's why I always solder and shrink tube all of my wiring.

If you have time look at the adjacent MOSFET's around it and get a part number...you might be able to order a replacement and solder it in. That's only if that part burning up didn't screw up anything else or the circuit board.
 
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with that being said are you running high or low impedance injectors?
 

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Discussion Starter · #11 ·
with that being said are you running high or low impedance injectors?
I'm running 680cc low with a res. box off of a V6 accord. Wires are solder(spelling) together and wraped up tight.
 

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Discussion Starter · #12 ·
That's not a capacitor. It's a MOSFET. Basically a high power transistor most likely used to drive the injectors(since I see a group of 6 there). It's possible that IF you upgraded the injectors..some of the wires may of shorted out due to bad wiring. Looks like one of those is seriously shot so you were probably running on 5 cylinders...hence why the car felt funny. Bad wiring or bad insulation can take a while to manifest itself. It might run perfect for a few weeks, but give it enough time with engine/road vibration and it will come loose. That's why I always solder and shrink tube all of my wiring.

If you have time look at the adjacent MOSFET's around it and get a part number...you might be able to order a replacement and solder it in. That's only if that part burning up didn't screw up anything else or the circuit board.

Felt funny yes, but why would my catch can be filled with fuel? I'm thinking with all the boost the valve seals has gone bad. Because if I do 5+ pulls my catch can is full of oil. After this it had fuel in it. I'm looking at a set of GTE internals now and I'm more inlikely going to pull the motor a rebuild it through and through.
 

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Felt funny yes, but why would my catch can be filled with fuel? I'm thinking with all the boost the valve seals has gone bad. Because if I do 5+ pulls my catch can is full of oil. After this it had fuel in it. I'm looking at a set of GTE internals now and I'm more inlikely going to pull the motor a rebuild it through and through.
Looks like an injector driver shorted out and blew, leaving the duty cycle on 100% due to the saturation of the transistor (MOSFET), causing the injector to run open, making it run full rich, which probably eventually fouled your plug in that cylinder, extinguishing the fire/spark, and you bypassed a shit load of fuel passed the rings, getting it sucked into the catch can under the high vacuum during deacceleration.

That'd be my guess. you might have had a little detonation to crack some rings or ring landings on the piston. Check your plugs, see what the y look like. See if any are discolored or oily or smell strong of gas. If you're catch can is full of oil after only 5 passes, I'd expect you might have already had some rings damage some time ago, that's a lot of oil if you truely mean "full".

After checking plugs, it's time for a compression check, all cylinders should be within 3-4% of each other and near 150psi I believe (I don't have the FSm's with me so I might be confused with another motor). If one or more are way lower than the others, you at least blew your rings or rings landings or perhaps chipped a valve if any chunks were flying (spark plug electrode, ring bits, etc...).

Good luck!

Kane
 

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Awesome trouble shooting provided in this thread.

When repaired find the resistance value of the OE injectors. Then add the resistance of the new low impedance injectors plus the resistance of the honda box. Looks like you were a good few ohms lower than stock even with the honda box.
 

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150 compression on all cylinders is on GTE internals if i'm correct and around 210 on stock compression. Someone correct me if i'm wrong.
 

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Discussion Starter · #17 ·
I have a new ECU on the way. I managed to find the part number off the pieces. NEC
C4814
1K 08
They all say the same. I have found a set of GTE rods, pistons and rings for $250. Someone know the best place to buy main bearings and rod bearings? They have 9000 miles on them. Been cleaned and checked to specs. When I do a compression check I'm affraid I'll find trouble. If I do, then I'm pulling the motor and giving the head a PP job. But will the factory valve seals hold up to what I'm going to place them through? I'm going to push the motor to the max my tranny can hold.(450hp) Once I get the race built tranny I'll go to 700+hp. Along with the GTE internals, I'm getting 264 HKS cams int/exh. Should I keep the VVTI though? I'm build a beast, other imput from my IS family would be great>:cool:
 

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Discussion Starter · #18 ·
150 compression on all cylinders is on GTE internals if i'm correct and around 210 on stock compression. Someone correct me if i'm wrong.
That might be. I have stock GE internals for now, along with the 2.8mm HG from SRT. So would mine still be 210 or lower?
 

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That might be. I have stock GE internals for now, along with the 2.8mm HG from SRT. So would mine still be 210 or lower?

Probably, biggest thing you're looking for though is inconsistency. A big drop of 5-10% less than other cylinders shows a major issue. Don't focus so much on if it's 150 vs. 210psi, look at each cylinder across the board.

I'll look through my FSM's tonight and see what it says.

Kane
 

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Compression reading should be around 192 psi with a minimum compression reading of 156 psi. There shouldn't be a difference in cylinder of greater than 14 psi.
 
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