15% ethanol in fuel 1

[3800sc]

I have a car with GM 3800 supercharged v6, 5 fuel injectors failed all at the same time. They would leak all the fuel line pressure into the cylinders/manifold making the car extremely hard to start.

The guy that fixed said he has been working on GM cars for 25 years and never seen five injectors fail at the same time in the same way ....he said the seats/seals in the injectors were eaten up

I am wondering if this could have been caused by the ethanol that is in all fuel these days (15% at stations near me)

 

[dgallup]

What year & where? What does he mean by seats/seals? These are totally different things made of different materials. We have done some pretty extensive injector testing on various ethanol blends and not seen much effect. Methanol is another story entirely. You didn't happen to use any of the various "miracle in a bottle" fuel/injector/top end cleaners did you? Many of those have very bad stuff in them.

 

[3800sc]

No i have always viewed those "cleaners" as snake oil, i did however one time have to use an octane booster because i let Mom drive the car and she put 87 in the car and it requires 93 octane with any amount of boost from supercharger. I should have cut one of the injectors in half and examined it myself. he did show me with fuel rail lifted up how they were leaking when keyed is turned on even tho car was not running....it just struck me as odd that he had never seen such a failure in 25 years

 

[evelrod]

Some of the so called "octane boosters" are mostly or contain a large percentage of methanol. However, I find it hard to believe one bottle would cause such a failure. Now. Having said that, there is also the possibility that you were victim of the automotive version of the "Perfect Storm"...BTDT !!!

Next time you inadvertently get a 'tank of regular', just take it easy on the throttle to a half tank or so and then fill-er up with 93.
We get a choice of 91 or 87 and I have a car that "requires" premium and I have operated it on "regular" for nine years/170,000 miles with no problems...in fact it has only had one set of plugs and one COP replaced in that time!
I do not use any of the 'snake oil' products, either. Waste of money...Same deal for the HUGE octane improvement of 'premium'.

Rod

 

[RossABQ]

Were they OEM seals, or replacements?

 

[3800sc]

oem

 

[izzmus]

I have a hard time believing anybody who had been working on GM cars since 1985 would not have seen injector failure!

It is a striking coincidence, but at the same time, the injectors are all equally old.

Could it be possible that one injector got to be bad enough to leak down at standard pressure, and as system pressure dropped, other injectors that could otherwise stay sealed would leak down?

 

[3800sc]

He said he had seen failed injectors but not several of them fail at the same time. your idea of one going bad then the others leaking as a result is interesting.

Although we had the fuel rail raised and when you turn the key on to build pressure then turn it off they all seem to start leaking at the same time so its hard to say.

I bought an entire new set and replaced them all just in case.

 

[RossABQ]

I'm not sure that's a legitimate test of O-ring integrity. It is usually performed just to see if the injector are spraying or plugged.

 

[turbocohen]

I don't care what anyone sez.. ethanol mixes over 8% accelerate oring failures and we would be much better off without it. Sounds like a crappy batch of fuel picked up what was in the tank or the filter was compromised internally.

 

[AviatorJim]

The senario I see on a pretty regular basis (privately owned airplanes), is that one part wears out, small loss of performance, the next part wears out, lose more performance, but blames it on something else (age, weather, bad gas), third part wears out, now it is hard to start, 4th or 5th part wears out, and the cummulative effect of all of them being worn out finally gets it into the shop to be fixed, and once the mechanic starts looking, 5 or 6 things are worn beyond the point of being servicable. Sounds to me like the injectors wore out one by one until the car would no longer start.