spurvo

Ummm... did I read right you are running 1300 cc secondaries on the stock ecu? So you have, what, 1.52 times the amount of fuel pouring out the secondaries (which come on at 3K) per given duty cycle than you would have with the correct 850 cc secondaries? Yeah, you might expect to run a little rich there...

Betcha the o-rings are screwed too. Pull that UIM ASAP, and look at the pressure regulator and pulse damper. If they look "old", then the guy who did the work REALLY made a mess, and this is one engine that doesn't forgive fuel messes. Were it me and I inherited this, I'd NOT drive it until I got the PFC and got that tuned, AND I'd replace the FPR and FPD just to make sure. I'd replace all fuel o-rings, and I might even send the secondaries to RC engineering to make SURE they work correctly.

my $.02

xxfetusmanusxx

hey guyz!! today i took off the uim and took a look arount and everything looked CLEAN then i cheked one of the spark plugs and it was soken wet in gas and all black... is it normal to be wet??? i let it sit for a while and then i noticed like a little dot of corrosion... how can that happen inside there??? could this be the cause of my problem?? maybe ignition or timing??

xxfetusmanusxx

wet

clayne

fetus,

The only way to figure out what the hell is going on here AND feel safe with this particular car is to pull the engine out entirely.

xxfetusmanusxx

Theres no one in montana than can work with these cars... it will probably be worst.
has anyone ever had or know of someone with a fully oppened fuel injector???

clayne

Yes. Many. There was always a reason for it too.

Disconnected FPR, bad electrical connections, etc.

xxfetusmanusxx

what would happen??? with a fully opened injector?? starts when ever it wants???, spits fuel out the exahust wille starting???, the fuel that doesnt spit out stays in the tube and ussually leaks through the dp gasket and manifold gasket???? i did find a burnt fuse in that little box where the fpr fuses r @.... something must of made that fuse to blow.... humm.... maybe i should keep tiping... im getting good ideas

clayne

A fuel injector is just a housing with an electromagnet inside. Generically it is a liquid flowing solenoid valve.

The electromagnet, when grounded (completion of circuit) actuates a plunger in the housing.
The internal plunger opens or closes the exit port of the injector.
The electromagnet is either on or off, on allowing fuel to flow through the injector and off preventing fuel from flowing through the injector.
The flow of the injector is regulated by connecting and disconnecting the injector's source of ground very fast.
This is done by using a squarewave signal with a variable period.
The variable period is defined as the "duty cycle."
The ECU regulates duty cycle based on negative or positive manifold vacuum and engine operating speed (RPM) by looking up injector duty values from a pre-mapped table (modifiable with aftermarket ECUs).
In addition to the variable opening speed of the injectors, the fuel pressure regulator increases fuel line pressure, by reducing the size of the fuel return path, based on negative or positive engine vacuum as well.
This results in a situation where increasing manifold pressure results in increasing fuel line pressure which means more fuel per on/off period of each injector.
Any unused fuel is sent out the fuel return line, back into the tank.
The fuel pulsation damper damps fuel rail pressure irregularities due to 4 injectors opening and closing very fast, simultaneously.

An injector open all of the time would dump fuel non-stop.

The only way you would have an injector open 100% of the time is if the injector is grounded 100% of the time OR the injector has an internal plunger failure (unlikely).
A disconnected fuel pressure regulator would result in high fuel rail pressure all of the time, causing injectors, operating at even normal duty cycles, to dump more fuel than they would in the same period if the fuel rail pressure was normal.