Well, i installed my return line and 650cc injectors yesterday to get fuel for my stage 3 hybrid, stage 1 ecm with stage 3 turbo. I have it set at static 43.5, car starts, but at idle its make pops, like its rich or something. I do have a safc and played with it alittle on the low throttle 1000 rpm side, but it does no good as it just corrects itself and still pops like crazy.
Drive it around for a couple days, it's most likely just the pcm re-teaching itself the parameters of the bigger injectors and it has to play with the duty cycles to get the car where it needs to be again.
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O4 PT Cruiser non GT
Stock b****es, come get me
Sporting new Nikon D40 w/18-55 & 55-200...it's a learning curve that's for sure!
I drove about 35 miles today, Ive read that you want to get your long term fuel trims as close to 0 as possible. Car has a slight stumble at around 1800-2000 rpm everytime. Car still pops like crazy at idle. I tried getting the long fuel trims as close to 0 as possible, roughly -3 to 3 at idle. Still pops. I see people all the time put stage 2 injectors on at 58 PSI of fuel pressure and still have a good idle, if im putting in less fuel at idle than stage 2's, why isnt anyone elses idle popping. Im sure someone can chime in on there stage 1/3 hybrids
Vac is normal 18.5-19 in hg. I did hook it up to a vac/boost source, thinking i had too much fuel at idle, but it still pops. So im just leaving it static right now. 43 psi. And hooking up to a boost reference when im 10.0 on the wideband with staic doesnt sound good to do.
Last edited by Natedogg2005 : 06-17-2008 at 02:23 AM.
Do you have any stock/S1/S2 injectors you could throw in to try out? You might have a clogged injector or somethin and the pops you're hearing could actually be a miss of some sort. Plugs and wires good? Everything set to where it's supposed to be on the safc?
i do have stock, which are the stg 1 injectors. I could throw them in, i have new plugs NGK's at .032 if i remember, and gueratellis(however its spelt) wires, both those have less than 4k miles. Safc, i tried messing with it on the low throttle at 1000 rpm, ive dropped it to 15%-20%, still pops. Ive tried zeroing out the long fuel trim, still pops and stumbles just alittle. I want these 650's to work since i paid 350 bucks for them from DW.
Last edited by Natedogg2005 : 06-17-2008 at 02:47 AM.
what I'm mainly concerned with is the settings on the safc...not necesarily the low and high throttle points and whatnot. I want to make sure, triple check that it's on 4 cylinders, and the arrow is pointing north east, with it set to pressure and 10in/10out. Once you've made it perfectly clear that those settings are in there, I would move to the old injectors and see what kind of change it makes. When you install the old injectors, raise the fuel pressure back up to stock and make no changes on the safc. If you are having issues still, then there's something else causing the problem. If the issue goes away, I would say probably most likely there's an issue with one of your new 650s
I checked the SAFC, 4 cyl, arrow pointing NE, pressure 10 in 10 out. So this is what should be happening- I should be able to drop 650cc's in no problem at 43.5 psi and the car should run like stock at idle?
Somewhat close...more like S2s stock at idle. S2 injectors are a tad bigger at stock fuel pressure than the 650s are at 43psi. If you have a buddy or something with S2, listen to his car closely, and you'll see there's a little bit more popping than there used to be with stock or S1 injectors in there. My car pops and spudders too, my fuel pressure is set to 47psi and I have the same 650 injectors you are referring to. The sound of the pops and whatnot...coming from a PT Cruiser nonetheless, is something I don't mind and like to hear lol. Doesn't bother me one bit
I just switched them out and it runs flawlessly. Well like i stated, it sounds like minor backfires, and the blurp from the exhaust doesnt sound consistent. at 1800-2000 rpm it sputters minor, nothing big but you can definetly feel it. I don't know anyone around here with an srt-4. i see them but thats pretty much as far as it goes, let alone someone with stage 2. Is there anyway to test the injectors? see if they are working correctly? I was hoping for a semi-stock running, but it doesnt look like ill be able to get that, i even dropped the fuel pressure down way low to see if the popping would go away, but it didnt.
I'm not sure of any local places in your area that could test them, but deautschwerks will perform a test/complete cleaning of them for a price...don't know what the price is though. You may want to get ahold of them and see what their prices and turnaround times are. If it's just minor popping though, it MAY just be something you'll have to get used to with larger injectors. I remember at 34psi fuel pressure my car sounded like it had crower S2 cams in it....I LOVED the way it sounded but it drove like shit! Once I raised up the fuel pressure the idle issue went away but it still pops quite a bit. Depending on what exhaust you have too might make a difference if you come to find that the popping sound is normal. A resonator will have a lot of pops and sputters, but an exhaust with an actual muffler will not.
well, according to the new gauge i have on the FPR, i had mine down to like 22 psi, but the FPR only does 30-70. The car sounded the same as it did at 43.5, you would think at 22 psi the car would die since its just fuel dripping by then and not atomizing.
I have an MPx full exhaust if that helps
Last edited by Natedogg2005 : 06-17-2008 at 03:40 AM.
Yes you are correct...at 22psi the car should have stalled out, or atleast showed major signs of being choked off. What kind of gauge do you have? Is it liquid filled, or dry? Also where on the vehicle is it located? If it's dry (no liquid inside it) they have a slight tendancy of being inaccurate at times. The liquid filling keeps them moving smooth so they're not all jerkey. If it's mounted on the rail or close to the engine, the vibrations can prematurely kill the gauge. Make sure it's mounted somewhere off of the engine securely and not moving around a ton.
Is there a way for you to get a quick vid and post it, just so I/we can hear how it sounds? We could be going on and on about something that's just plane out normal here and I could be racking my brain over nothing at all haha.
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Pops at idle
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