Am I running out of injector?

[GTPpower]

Finally got my 04 Comp G running decent....had a clogged cat. But, I did some scanning, and my injector duty cycle reaches 106% at 5500 rpms, where it shifts. Is it possible that it's already out of injector? Or would a failing fuel pump or restrictive fuel filter be more likely? Not sure how much power these can make with the stock returnless fuel system.

Mods are:
XPZ
Ported heads
L26
3" catless downpipe.

Everything else is completely stock, including the supercharger pulley. Stock injectors, stock wiring...the car has 108k miles, and it sat for 2 years without running/moving.

I didn't have the wideband hooked up, or a fuel pressure gauge. My MAF was showing a little over 10k hz at the shift, and 30.8lb/min. Narrowband O2 is sticking in the 900's at WOT.

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[Eagle]

Stock injectors? If so, yeah, you're out of injector.

 

[1quick]

yeah prolly out of injector, the returnless can be made to make decent power but it takes more pump than a return system does, if your just running gas and not e85 you could prolly get away with a rewire and some 42's, i had to run 42's with just an s1x cam and headers and a 3.2 pulley on my other car

 

[GTPpower]

I have a set of 42's that I used a few years ago on my 01. Did you use the connection adapters, or just get EV6 injectors? I'm not convinced that adding 2 more connections to the injectors is the best idea.

 

[1quick]

i used the adapters on my 06' my current car has the ev6 injectors, i eventually went with 65's and e85 on the 06' and when i did that i also went with the ev6 injectors a rewire and a walbro 255

 

[PANDA]

What kinda setup is that? Unless you are going for the "stock" type deal. Get some headers and injectors on that car. XPZ and stock injectors, yeah Id say you are running out of injector. Also change the fuel filter anyway, you should do it every year. Cheap insurance. If you are doing any sorta tuning get a wideband. You probably know this already.

 

[GTPpower]

i used the adapters on my 06' my current car has the ev6 injectors, i eventually went with 65's and e85 on the 06' and when i did that i also went with the ev6 injectors a rewire and a walbro 255

Hmmm...ok. I think I'll probably just get some 60's with EV6 connectors. Not planning on running E85 anytime soon, but there is good chance I'll intercool it. How far will the factory fuel pump take me?

 

[GTPpower]

What kinda setup is that? Unless you are going for the "stock" type deal. Get some headers and injectors on that car. XPZ and stock injectors, yeah Id say you are running out of injector. Also change the fuel filter anyway, you should do it every year. Cheap insurance. If you are doing any sorta tuning get a wideband. You probably know this already.

Screw headers....I'm sick of exhaust leaks. This is my daily...I'm enjoying a nice, quiet car for a change.

I agree the fuel filter needs to be changed. Just haven't done it yet because no local parts stores stock it. I'll just have to order one.

It just blows my mind that I'm maxing injectors with a stock pulley. I have stock injectors in my 01.

 

[1quick]

Hmmm...ok. I think I'll probably just get some 60's with EV6 connectors. Not planning on running E85 anytime soon, but there is good chance I'll intercool it. How far will the factory fuel pump take me?

i was 280whp on the stock pump set up with no rewire, you could maybe squeak 300 or a little more out of it with a good rewire

 

[Handsome Jesus]

I have a set of TOGs for sale

 

[GTPpower]

i was 280whp on the stock pump set up with no rewire, you could maybe squeak 300 or a little more out of it with a good rewire

Ok. Thanks.

Do the 04+ use the same rewire as the 97-03?

 

[GTPpower]

I have a set of TOGs for sale

Damn. The only set of headers I would feel comfortable with. Do you have a FS thread?

 

[1quick]

Ok. Thanks.

Do the 04+ use the same rewire as the 97-03?

yeah i got mine from ractronix

 

[GTPpower]

Ok. I have a Casper's on my 01...I guess I could rob it off that car if I need it.

Thanks for all your help.

 

[Turbocharged400sbc]

check with a wideband but you may be rich

the stock manifolds and a stock pulley would suggest that your not too far off oem airflow numbers so you should be ok.

narrowbands can read from mid 800's to mid 900's
they are lousy at measuring anything other than stoich

 

[GTPpower]

check with a wideband but you may be rich

the stock manifolds and a stock pulley would suggest that your not too far off oem airflow numbers so you should be ok.

narrowbands can read from mid 800's to mid 900's
they are lousy at measuring anything other than stoich

That is what I was hoping for. Maybe if I feel ambitious tonight, I'll toss in the wideband and see where it's really running at.


Do you know of a good pressure sender (for fuel) so I could just hook it up to inputs on the tuner? Probably don't need a gauge for this car, but it would be alright just to see where it's at.

 

[Turbocharged400sbc]

you could set PE enable to 100% tps and go for a drive and find your stoich maf numbers for the low/mid of the maf which should be able to tell you more without installing the WB

you can get a 5v powersupply and the sender without the gauge

 

[02BlueGT]

James: "you have a tuner? You should turn off PE and drive the car around."


Just put in the wideband, why bandaid it if you have the sensor anyway.

 

[Turbocharged400sbc]

DAVES NOT HERE MAN




he's right you should install it and get comanded and actual to jive, just remember the factory pe/rpm/time puts you real rich after just a couple seconds while in PE

 

[boostedguy05]

if i am not mistaken the fuel filter is in the tank and part of the pump. that is why nobody has them in stock because it is part of the fuel pump.

 

[1quick]

if i am not mistaken the fuel filter is in the tank and part of the pump. that is why nobody has them in stock because it is part of the fuel pump.

04's had one and its different than the older gp's I think everything newer than 04 doesn't have one out side of the tank

 

[boostedguy05]

ah. i know mine is in the tank and not ment to be replaced untill the pump goes out.

 

[SaturdaysGS]

I believe I just used a regular 03 GP fuel filter when I did mine... Can't remember for certain though.

 

[Turbocharged400sbc]

05+ are fucked
the rest use the same part number

 

[RICH17]

Some 04's had fuel filters and some didnt.

Because GM