Fuel injectors

[sharky559]

yea im going to put a walbro 255 fuel pump on my 95 eclipse gst but i need to find out what kind of injectors will i need.

 

[Gasolinebaptism]

Is this supposed to be a question?
If it is you need to give us specific details about your car. and you won't necessarily need new injectors. but for sure you will need an aeromotive fuel pressure regulator. (AFPR)
So give us some info on the car, and your goals.

 

[hondaslayer1]

on a close to stock car u need a adjustable fuel pressure regulator with a gauge and thats to help with the 255. what maKES U THINK U NEED INJECTORS TO SUPPORT a walbro 255. are u trying to upgrade your whole fuel system. are u hitting fuel cut. we kinda need more info .

 

[Gasolinebaptism]

Uber n00b?

 

[sharky559]

sorry people. the thing is im running rich and someone told me to put a better fuel pump. the car does have a afpr. to check, if the fuel injector harnest worked i tested it with a noid lite and the computer is sending good signal. but if im running rich that means im getting to much gas so the injectors are the ones that are not working. could someone help

 

[Gasolinebaptism]

No no no. If you're running rich there is leftover unburnt fuel in the exhaust, that's okay, over time running extremely rich it can pose a problem. If you're running rich and already have an AFPR then just adjust it, because going to a larger pump would just cause you to run even more rich, and doesn't hat completely defeat the purpose?
But then again, you havn't told us Shit about your car.. is it completely stock except for the AFPR? It can't be, that doesn't make sense..

 

[sharky559]

yea my car is all stock. only the afpr is on the car.

 

[Gasolinebaptism]

well, is it adjustable? and do you still have the original laying around?
What are your plans for the car? Do you want to upgrade the fuel system so it will be ready for a new turbo?

Test your fuel pressure, it should be 43.5 or so with the vacuum line disconnected, and mid to upper 30's with it connected. Figure that out, and adjust the FPR til it's right on, then you should not longer run rich. If you still run rich, it could be the Mass Airflow Sensor, or O2 sensor. Just the first thinks that come to mind.. But it could also be the Coolant Temp sensor. And you need to keep in mind, the ECU on these cars selects a fuel trim that runs slightly rich throughout the rev range, and even more so when cold.

 

[sharky559]

so far this what ive replaced on the car.O2 sensor the one after the cad. coolent temp sensor, tps, maf, and map sensor. o yea i also took out the old pfr and put a after market pfr. but still its running rich. also i have a feeling my fuel system could be looseing pressure. also could that lead to a hard start. could someone help.

 

[BigBeans]

Baptism is on point. If all you changed was the afpr and it started running rich you need to set the base fuel pressure to 43psi, with the vacuum line disconnected. when you reconnect the vacuum line it will change the pressure, which is normal.

If that is correct than the MAF could be the issue. Also you replaced the wrong 02 sensor. The car runs off the first one, the one after the cat is only to test the efficiency of the cat for emissions.

 

[Gasolinebaptism]

You keep saying that you "think" you're losing pressure, you "think" this, you "think" that.
What your symptoms are saying, is that because you replaced the FPR the fuel pressure is too high in the line, not low. And since the FPR isn't set at the right spec, there is too much fuel going into the combustion chamber, and this will cause a hard start (flooding) and running rich. That is your problem buddy.

 

[sharky559]

ok this is what happends to the afpr when i turn off the car. the pressure gauge on the afpr drops to 0. it should stay at a sertin psi right, could someone help

 

[Gasolinebaptism]

Well I'm not really sure how AFPR's function, but I think I know the basics pretty damn well. It's a mechanical springloaded valve. and it seems like that pressure ought to hold for awhile and slowly decrease.. but maybe they don't. What is your gauge telling you at idle?

 

[sharky559]

the gauge marks 33psi but if incres the psi the car will want to shut off. and then the gauge drops from 33psi to 0 psi.

 

[jrohner]

You're getting too much fuel, so someone suggested you get a better fuel pump so you can get even more fuel?

My suggestion is don't ask that person for advice again.


If your fuel pressure drops when the car is shut off, you probably have a bad AFPR or a cheapo ebay one. That will make the car start crappy.

Do you have some kind of logger so you can see fuel trims? Also, make sure you adjust base fuel pressure with the vacuum line OFF the AFPR and plugged.

 

[sharky559]

ok i see. im going to see what happends and by logger you mean like a safc right

 

[jrohner]

No. A logger is how you get the data to know how to tune it, the afc is what you actually tune it with.

You use software and a cable hooked to a PC or PDA to log.

I would go with a chip not an afc, but that's a whole different topic.

 

[Gasolinebaptism]

Well you have to be more descriptive, does it just sound like the car floods out if you adjust the AFPR higher? because it could be that the have larger than stock injectors (for no apparent reason) and this would mean that more fuel will pass at a lower rail pressure.
But hook up the new fpr in the morning, I suggest a stock one. And get back to us with what happens.

 

[sharky559]

yea i put back the stock fpr. it took a while to start it but i started the car. but still running rich and the big cloud of black smoke. but as soon as i gave i gas about 2000 rpm it sounded not right

when i replaced the tps i just slaped it on and didnt adjust it could that be the problem?

 

[Gasolinebaptism]

Definitely a problem.
Because the TPS tells the ECU how much gas you're trying to give it, if the TPS says you're trying to give it some gas, but the throttle plate is still closed, only allowing enough air by to idle.
So fuel is getting dumped in but not not getting any air to burn it with.

 

[sharky559]

damn im going to adjust the tps and i also got a hold of a logger. thanx gasolinebaptism and the others that helped

 

[Gasolinebaptism]

No problem man.
Search the forum to figure out how to get it adjusted, take a log, and post it.
Feel free to PM me with any questions. Or shit.. just to notify you've updated the thread and I'm not paying attention. haha.