Lexus SC300 Wont Start

HeX

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After no progress researching this online, I've decided to seek help from the knowledgeable minds here. I hope at least someone hear is familiar with SC300s.

I attempted to install a used distributor in my friends 1997 Lexus SC300 (automatic) because the original distributor's internal seal was leaking oil. After swapping both, the car wouldnt start. I checked that all was set on cylinder one including manually setting the piston to the top dead center. Still nothing. I swapped in the old functioning distributor to help rule out the recently purchased used distributor, and still no start. I installed a new cap & rotor just in case then, and still no start with either distributor. He had his mechanic friend came over, changed the spark plugs & wires, reset all to top dead center, and confirm there is spark with the newer distributor. Again, no start. Each time the car is turning over but just wont start. All harnesses are plugged in. There are no observable broken wires or damaged parts. All fuses have been inspected. We scanned the ECU and there are no codes.

We're not sure what else to consider being that we're not familiar with SC300s. My only two remaining guesses are as follows. 1: The igniter decided to crap out randomly. 2: Perhaps the alternator is somehow causing this. The reasons I mention the alternator is because the distributor leaks directly onto the alternator & my friend had this leak for months & wouldnt address it,which is why I offered to help. Also, the battery drained in the month the cars been sitting in his garage, so we installed a new one. I havent noticed any typical electrical issues that are common with alternator issues though. The only next option may be towing the car to a shop so they can dissect it. I hope to figure something out before that.
 

lethal6

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You haven't mentioned anything about fuel. Is it getting fuel?

An alternator isn't used until the car is running. It's job is the charge the battery or to keep the battery fresh. It has nothing to do with starting it with the minor side note being that it could be the alternator's fault the battery is dead therefor causing the car not to start. Meaning that it killed the battery, but the car will still start with a dead alternator and a dead battery if jumped. If you jump the car, it will run until a good battery source is removed.

By the way, it doesn't matter if it is a civic, a lexus, or a piece of s**t ford. All combustion engines need 3 things to run. Air, fuel, and a spark to ignite that mixture. You aren't getting one of them.

Is the timing correct or did you mess it up when messing with the distributor?
 


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HeX

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You haven't mentioned anything about fuel. Is it getting fuel?

An alternator isn't used until the car is running. It's job is the charge the battery or to keep the battery fresh. It has nothing to do with starting it with the minor side note being that it could be the alternator's fault the battery is dead therefor causing the car not to start. Meaning that it killed the battery, but the car will still start with a dead alternator and a dead battery if jumped. If you jump the car, it will run until a good battery source is removed.

By the way, it doesn't matter if it is a civic, a lexus, or a piece of s*** ford. All combustion engines need 3 things to run. Air, fuel, and a spark to ignite that mixture. You aren't getting one of them.

Is the timing correct or did you mess it up when messing with the distributor?
I know most of that info about the alternator but I threw it out there incase there was something I wasnt aware of.

We know its getting fuel because you can smell it when trying to start it & upon removing the old plugs they appeared moist. Originally I thought Imay have thrown it off timing, but as I stated earlier, we repeatedly reset it at the distributor & setting piston one to the top. My friends mechanic also checked it at the came gears to see if there was an off tooth from the timing belt.
 

RonJ

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Is there bright white spark at all the plugs?

Are the plug wires installed in the correct firing order on the cap?

Is it possible to install the distributor 180-degrees out of phase?

Are the cylinders flooded with fuel, causing low compression?
 


lethal6

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I know most of that info about the alternator but I threw it out there incase there was something I wasnt aware of.

We know its getting fuel because you can smell it when trying to start it & upon removing the old plugs they appeared moist. Originally I thought Imay have thrown it off timing, but as I stated earlier, we repeatedly reset it at the distributor & setting piston one to the top. My friends mechanic also checked it at the came gears to see if there was an off tooth from the timing belt.
Good, so it's definitely getting fuel, but you said plugs are moist. Is there a lot of fuel flooding the chambers?

Also, if it is possible to install the distributor 180 degrees out, it doesn't matter if you put the pistons at top dead center. If it is 180 out the car won't start.

If it ran fine before the dizzy change, that is the likely possible problem being that there is something wrong now right after fussing with one. Like ron said, are the wires for sure in the correct order? Is it 180 out?
 

HeX

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Is there bright white spark at all the plugs?
I was turning the key when the mechanic inspected the spark, so I dont know the color. We also only checked the first 2 plugs because the other 4 are buried under the manifold. Keep in mind though there is no misfire when we turn it over.

Are the plug wires installed in the correct firing order on the cap?
If it ran fine before the dizzy change, that is the likely possible problem being that there is something wrong now right after fussing with one. Like ron said, are the wires for sure in the correct order? Is it 180 out?
Yes, all the plugs were in order before & after the new plugs were swapped in. Ive backtracked every single step and cannot find anything I came in contact with that could cause this issue. The fact that another mechanic also checked adds to the mystery.

Is it possible to install the distributor 180-degrees out of phase?
Also, if it is possible to install the distributor 180 degrees out, it doesn't matter if you put the pistons at top dead center. If it is 180 out the car won't start.
The end of the distributor is actually a gear with curved teeth, not like the U-shaped fork our hondas have. Both of us actually tried to line up the teeth in the three teeth closest to being around 1. The Lexus distributor also has line-up marks along with where it goes in so you cant really misalign it.

Are the cylinders flooded with fuel, causing low compression?
We didnt test compression, but I attribute the moisture from multiple attempts at trying to start it to no avail.I'll suggest compression testing next time he's around but Im not aware that compression would cause no starting at all.

Good, so it's definitely getting fuel, but you said plugs are moist. Is there a lot of fuel flooding the chambers?
None that we observed. Just moisture from pumping the gas a bit to see if it'd start.

This constant ambiguity is why I hope theres a member with experience with these cars. I'm heavily inclined to believe it must be something specific to this engine we're just not aware of.
 

RonJ

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You need to know the spark color at all 6 plugs.

Keep in mind though there is no misfire when we turn it over.
How could you possibly know without the engine running?
 

HeX

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You need to know the spark color at all 6 plugs.
Please explain further. Ive never heard of this.

How could you possibly know without the engine running?
Because its smoothly turning over. I should've better said that it feels like its firing in order.
 

RonJ

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Please explain further. Ive never heard of this.
It's pretty basic. You checked spark at 2/6 plugs. You need spark at most of the plugs for it to start and run. And if spark is weak at all plugs, then again, the engine won't run.

Because its smoothly turning over. I should've better said that it feels like its firing in order.
The engine is being cranked by the starter. There's no combustion, so you have NO IDEA about firing order, right? Don't over-interpret information.
 

lethal6

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Texted a buddy of mine that used to work for Lexus before he started working at Porsche with us. He said it is definitely possible to install the distributor 180 degrees out. He also said to make sure that the top wire goes to plug number 1, if it doesn't you either have the wires wrong or 180 out.

I am still under the belief that it has something directly to do with the wires or the distributor being that it ran fine before you pulled it out. If the wires are mucked or it was 180 out putting the old one back in will still reflect these mishaps as they would be directly duplicated. It isn't common for problems of a whole other nature to surface. If it was fine before something was taken out, it usually has to do with the reinstall or something that was unplugged to get that component out.

It doesn't really matter if this is a lexus, honda, toyota, vw, etc. A car is a car. Some of the best mechanics I have ever met work on anything no matter the make.
 

SpeedTechnik

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Ah, the infamous 2jz-ge engine in the ol sc300. I'm sure i dont need to reiterate but I can't elaborate more on what has been said. The 2jz isn't any different from any other engine . It is difficult to work on and suffer from things like relay failure, severe vacuum leaks, but its nothing you won't find in any other old car. Yet, I'm sure that this has to do directly with Ignition timing.
 

HeX

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Update

My friend took the SC300 to a mechanic with experience on those engines and he got it to run. As many suggested, it was a case of the timing being off. Apparently I just didnt get everything lined up properly. What I had off exactly will remain a mystery. I learned my lesson not to mess with that engine & stick to simple Hondas.
 


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