Ok, I should re-phrase that, I know injectors have limitations, but what exactally happens (to the injector, motor, and fuel pump) when it does reach it's top performance level?

Also, a sub question, if you are under heavy load, full boost, and an injector fails would you distroy your motor because it went lean instantly? (Has this happened to anyone?)

 

An injector can only flow so much fuel at a certain pressure. Exceed that and . you can cause serious damage if you lean out one or more cylinders, especially while under high load and high RPM. Cylinder temps will go up and detenation will occur.
Broken ring lands and melted piston domes are common when this happens.

I have had a couple of customers that had to repair a freshly built engine do to a faulty injector. Both of them bought the injectors off of EBay and didn't have them checked out first.

Gordon
WitchHunter Performance
http://www.witchhunter.com
Fuel injector cleaning & flow testing service

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Honduh Chicken &raquo;</TD></TR><TR><TD CLASS="quote">Ok, I should re-phrase that, I know injectors have limitations, but what exactally happens (to the injector, motor, and fuel pump) when it does reach it's top performance level?</TD></TR></TABLE>
Switch covered this and made a good point about getting used injectors cleaned and flowed before install.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Honduh Chicken &raquo;</TD></TR><TR><TD CLASS="quote">Also, a sub question, if you are under heavy load, full boost, and an injector fails would you distroy your motor because it went lean instantly? (Has this happened to anyone?)</TD></TR></TABLE>
Injector failure is VERY rare if you have a good quality injector. If an injector were to stop flowing fuel entirely you'd have spark in an empty cylinder which would not cause immediate engine failure. However, you are still spinning your motor with the other 3 cylinders and the load is now out of balance. Inevitably you'll run into problems if this happens. For reference, flat shifting and launch control are often achieved on cars without nitrous by sparking cylinders without fuel. If an injector seized on a race motor running a lot of power, you'd see failure from this more quickly of course.

A more common problem would be a dirty or partially clogged injector flowing less fuel than the others. This can result in engine failure as Switch mentioned from overheating and detonation in that particular cylinder.

-Mike

 

Ok, that leads to another question, if the injector plug were to come off, or the injector wire between the plug and ecu failed.. Does the injector stay "open" and allow the fuel pump to continously spray fuel into the engine? or when it has no power is it in the "closed" position?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Honduh Chicken &raquo;</TD></TR><TR><TD CLASS="quote">Ok, that leads to another question, if the injector plug were to come off, or the injector wire between the plug and ecu failed.. Does the injector stay "open" and allow the fuel pump to continously spray fuel into the engine? or when it has no power is it in the "closed" position?</TD></TR></TABLE>

it would close instantly

 

if fuel stops coming in you will go lean and then boom.

 

no if there is no fuel coming in it will not go boom because there is no fuel the air and spark need something to burn with

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dunkd &raquo;</TD></TR><TR><TD CLASS="quote">if fuel stops coming in you will go lean and then boom.</TD></TR></TABLE>
not true
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vaporboy12 &raquo;</TD></TR><TR><TD CLASS="quote">no if there is no fuel coming in it will not go boom because there is no fuel the air and spark need something to burn with</TD></TR></TABLE>
Exactly. If you pull a spark plug out of the head, hold it in the air and turn the motor over, you won't blow up your garage...unless you have a massive natural gas leak in your garage or something. Think about a compression test...spark without fuel....no boom, no engine damage.

-Mike