Perpetrator: Injector O rings!

[MisterTurbineTwister]

My brother was driving the Supra the other day and I noticed a horrible smell coming from the engine bay. We got home and I noticed a fluid dripping onto the ground from under the hood. I immediately shut the car off, went inside and grabbed a flashlight, came back outside, fired it up again and found that the fuel injector on the #3 cylinder was leaking fuel at the rail.

I pulled the ISC valve, the 3000 tube, the Throttle body and TPS and the fuel rail and replaced all 6 of the o rings that seat the injectors into the fuel rail... End of fuel leak problem.

We test drove the car once we put it back together and it ran fine until he came back from his friends house and said the car had some kind of misfire.

I figured that maybe one of the wires had come loose on the coil from removing the coil cover and the 3000 tube, so after I got expected to and did get shocked, I discovered that the wires were fine when I checked the connections of each one and they were okay, but the car still had a misfire.

I started to notice a hissing sound like a vacuum leak coming from the front side of the engine on the intake side and after about 45 minutes of studying the sound, turning the engine on and off, checking ALL of the vacuum lines and hooking my vacuum gauge up to the intake, I still couldn't locate the vacuum leak or figure out why the car had a misfire that would go away at low vacuum level (above idle).

I listened with a stethascope and after looking closely, I discovered that one of the O rings on the #1 Cylinder that seals the injector to the head had shattered upon reinstallation and created a single cylinder vacuum leak (which would explain the misfire at low idle only)

After accepting the fact that I had to take it all apart again, I took all of the injectors out along with the O rings and inspected all of them. To my discovery, I found that nearly ALL of the O rings had fractures in them causing a small amount of vacuum leak on all 6 cylinders pulling in unmetered air!

Knowing that the vacuum drops at above idle to zero and then increases in PSI of boost I shortly realized that it was also in turn a boost leak.

I was blaming some of the very very slight stumble that I had at idle on the ISC valve. It was ALWAYS the @&!!*&!!! injector to head o ring seals causing the problem from day one and it wasn't enough to show up on my vacuum gauge.

I RTV sealed a paper thin layer on the injectors and the o rings and installed them in the block and that has been the end of ALL of my small idle problems and I actually am showing 1.5-2 LBS of more boost!

I am not planning on keeping the O rings in there that long, it was just that it was 4 am when I fixed the problem and my brother needed the car for work at 8am that day, so I had no choice.

I would suggest to ANYONE experiencing any problem with idle, slight or not to replace all of your injector O rings. I couldn't believe the difference in fixing the slight fractures in some of my O rings and I haven't replaced them with new ones yet!

Can anyone give me a lead on a set of injector O rings (the larger ones that seal the injector to the head) and a price? For some stupid reason, I can't get them at a parts store here.

Thanks.

 

[foofers]

I'll have to make sure to inspect and most likely replace my injector o-rings.
You have to dip the o-rings in fuel to install them onto the injectors and when seating the injectors in/on to engine?

On a side note: Is it normal to get shocked when touching one of the spark plug wires while the car is running? I was pushing the wires in, making sure my were all securely connected to the ignition coil and....zap.

 

[Bishop92t]

Toyota sells the injector o-rings surprisingly cheap. 18003272087 ask for Jeff Watson.

foofers, your plug wires are bad, that is not normal.

 

[drjonez]

watch for the grommets in the head to pop out under high boost....makes for a fun time....

 

[Idealsupra]

Toyota sells the injector o-rings surprisingly cheap. 18003272087 ask for Jeff Watson.

foofers, your plug wires are bad, that is not normal.

or just go to auto parts store...full kit for 8 bucks...

 

[MisterTurbineTwister]

You shouldn't experience any shock from the wires unless you actually have pulled the wires from the coils, then you would probably experience electric shock.

If you know that the wires are seated and you touch the wire and experience shock, you could have a bad wire, but it all depends on how many amps and volts you are pushing through the wire and how and where you touch the wire and if the wire is making full contact.

My Jacob's Pro Street box delivers 65,000 Volts peak power and I have been zapped on a brand new set of wires because I touched it at the distributor cap and it made an arc through my body and out of my other hand that was touching the bare aluminum intake manifold... That put me down and it took me about 30 minutes to recover from. I'll never touch an ignition system with an amplifier or capacitive discharge ever again while the engine is running.

Also, foofers, you shouldn't need to prime the O rings that seat into the fuel rail or on the head with anything at all. You can use a little bit of engine oil if you are having trouble with them installing, but nothing is required.

Thanks for the lead on the O rings bishop. I'll be calling him on Monday.

I just figured I'd post this because I know a lot of people have some minor issues with their idle and this took care of all of my idle problems and it seems that it would be a commonly overlooked issue and it doesn't realy touch on it in the TSRM specificly... It just states that poor idle can be caused from a vacuum leak in general, which can be true, but if all of the other 15 year old Supras running around this site have the original injector O rings on them, this could help a lot of people solve some idle and minor boost leak issues.

 

[Bishop92t]

MisterTurbineTwister - good idea, it's an often overlooked yet vital part to a healthy motor.

BTW I like how you phrase it "experience electric shock". I've been zapped by my stock N/A, my N/A with an ignition upgrade, and my turbo. I must say the N/A with an upgraded ignition rocked my world, whole arm was numb with a nice copper taste for the rest of the day

 

[drjonez]

the reason you can easily get shocked on ign wires is that the V is actually traveling on the OUTSIDE of the wire....in theory it should be beneath the rubber, but all it takes is a thin point and it'll jump right through it.

 

[mrnickleye]

The bosch injector seal kits are what you need. Any parts house will have them for about $10 for the 6 set. Was cheaper than toy dealer cause each seal is sold seperately.