Hi guys, I am looking to do a fuel system refresh and I am replacing my pump, pulsator, sending unit, filter, pump lay, and I'm toying with the idea of replacing the fuel injectors. I am considering the 15lb accel units shown on the fiero store website and I was wondering if anyone had any experience with them and could give me some advice or guidance toward this item or an alternative??
I had the injectors in my 86 GT sent for cleaning at about 195,000 miles. They came back as basically non-functional - the car ran so lean that I couldn't go more than 30 mph. I got some Multec / Tomco injectors out of a Beretta in the junkyard and the car ran fine afterward.
Just recently I replaced my Multecs with a new (not rebuilt) set of Standard FJ27 injectors, thinking the old Multecs were worn out and/or dirty. The car runs exactly the same before and after the new injectors. Ironically, the car also runs the same as it did with the OEM injectors at 195,000 miles.
My point: Unless you have reason to believe your injectors are causing a problem, i'd leave them alone. I've also had good luck with the Multecs from the junkyard, they are very cheap this way (~$4 a piece). Just bring an ohmmeter and measure each coil's resistance before you buy them. They should be about 15 ohms - if they're low they have a shorted coil, the most common failure point of this type of injector.
I have a mounted set on a new fuel rail sitting idle. They were originally bought for the rebuilt engine, but I didn't use them. They appear to be stock Delco
If you do want to have yours rebuilt, www.fuelinjectorconnection.com is a little closer than Michigan. They will even flow match them for a slight additional charge.
If you want the original injectors I'd send them out to one of the rebuilders. [edit: retracting something I wrote here that I think I might have been wrong about.] Multecs have a much better spray pattern, but have a reputation of being long-term unreliable. They might have some subtle mistuning issues with the stock ECM programming. So you can make a decent argument for using either type.
You can get refurbished and flow matched Multecs from "Precision Auto Injectors" for pretty cheap. http://www.precisionautoinjectors.com/ They have the 2.8L injectors listed under Chevrolet injectors. I ordered the ones for an 85-89 Camaro 2.8, but honestly I think for any of the 6 Chevy 2.8/3.1 listings he probably sends you the same injectors. The injectors he sends out are 17lb/hr Multecs, not the 15lb/hr pintle type which were original on the Fiero. I mentioned on my order that my injectors were 15lb but apparently 17lb is all he has. More precisely I think the flow rate is 16.6lb/hr. Negative points - I didn't get a flow report with my order, and he didn't reply to an email I sent afterward. Positive points - The injectors were good. The car accelerates smoothly now and it fixed a stumble I had at light acceleration. It noticeably drives better with these injectors than my old ones. Cheaper than other refurbs I found for sale.
Minor ECM concerns: 1) The way Multecs respond at low pulse widths isn't the same as the original injectors, and I believe this may contribute to a hunting idle scenario. Some people have had that problem and some don't. It's preferable to make a new chip for the Multecs, but they'll work okay with the stock chip. 2) The difference in overall flow rate (16.6 maximum vs 15lb maximum) is something the ECM will adjust for, except it will ignore that adjustment at full throttle. So without retuning it will probably run more rich than stock at wide open throttle, but under normal driving operation they will be the same.
I inherited old Multecs on my car and have always had a hunting idle on it. The new multecs fixed my stumble at light acceleration and it drives smoothly now, but the idle issue remains. I experimented with using the injector tune from some later, Multec equipped cars. I recently tried one that seemed to fix the hunting idle but it didn't accelerate as well, so I stopped using it. I can't prove that the injector tuning is what causes my hunting idle, but from what I've experimented with I suspect it to be the case. I neglected to write down the part number on the injectors I received from PAI. Now that they're in the car I can't read them. If I had that number I'd try to find exactly which car they were original to, and look up that ECM program.
If you don't mind spending more money and feel adventurous, somebody has 17lb/hr Bosch "Type III" injectors which are supposedly God's gift to gasoline. I can't remember which rebuilder was selling them, but it was I think $150 for a set of 6. I thought it was FIC, but I just checked their site and it doesn't look the way I remember and I couldn't find anything.
[This message has been edited by armos (edited 06-26-2012).]
I found the Bosch Type 3 injectors for the Fiero 2.8. $269.50 http://www.fiveomotorsport....duct-search/?v=22232 I'll hopefully get them in this week and let everyone know how they make the Fiero run.
I've always been told here over the years, that the pintle-style injectors are far superior to the disc-style of injectors. I don't know if I'm just repeating bad information, but if that is in fact true... then you could try getting a set of Accel injectors. I bought a set from them (from Summit) several years ago. I got the 17# injectors to go with my 3.2l rebuild.
I was all excited about the Bosch Type 3 injectors. When they arrived, I was confused. There are no rail clips on them. I read on other forums they are supposed to seat fine between the block and rail without them. I set them into the block as told then set the rail onto them. It looks nice except as soon as I fired up the fuel pump, gas plowed out around the top of the first injector. I adjusted it and tried again then the ones on the other side leaked. At this point, I realized this is way too dangerous and pulled them. Now I'm hoping the guy at Five O will accept the returns... This is a true bummer. Now I'm torn between cleaning out the originals or trying to purchase a new replacement version with the fuel rail clips...
Fuel injectors are expensive, your better off doing an engine swap.Been there done that...what a night mare.Fuel leaking all over the place! Make sure you use vasoline on the injector O-rings dureing the install. If it works, don't fix it.
There are no slots on the new injectors. I actually tried putting the clips on the new ones in roughly the same place but the diameter is slightly larger so they would not lock. As it turns out I measured them O ring to O ring and the newer ones were about 3/16 inch shorter. I'm certain if they were the same length they would have worked perfectly.
There's a guy in Dallas (local) to me who specializes in 9800 SC engine swaps. The end result delivers a 4.0 second Fiero. This service costs 10K. Hardly considerable when I can buy 6 new Accel fuel injectors for around $200.00. These claim to deliver way better fuel economy and more HP as well. Guess I will try these next. http://www.summitracing.com.../pontiac/model/fiero
Originally posted by maxout2: I was all excited about the Bosch Type 3 injectors. When they arrived, I was confused. There are no rail clips on them. I read on other forums they are supposed to seat fine between the block and rail without them. I set them into the block as told then set the rail onto them. It looks nice except as soon as I fired up the fuel pump, gas plowed out around the top of the first injector. I adjusted it and tried again then the ones on the other side leaked. At this point, I realized this is way too dangerous and pulled them. Now I'm hoping the guy at Five O will accept the returns... This is a true bummer. Now I'm torn between cleaning out the originals or trying to purchase a new replacement version with the fuel rail clips...
Darn, I had thought about those as a future possibility, and really hoped they'd work. Thanks for posting the results anyway.
But there's hope - while looking for something else, I saw this: http://www.youtube.com/watch?v=_rz76KiE3RY SouthBay Injectors claims to have an adapter to make these fit. On that video they're talking about fitment to "TPI" V8 cars but you might ask them about fitment to the 2.8L. They participate a lot in the thirdgen.org (F-Body) forums and seem to have kept up a reputation.
I've always been told here over the years, that the pintle-style injectors are far superior to the disc-style of injectors. I don't know if I'm just repeating bad information, but if that is in fact true... then you could try getting a set of Accel injectors. I bought a set from them (from Summit) several years ago. I got the 17# injectors to go with my 3.2l rebuild.
The Accel injectors are all floating disc style injectors, not pintle style! Go to the Accel website and read up on them.
There's a guy in Dallas (local) to me who specializes in 9800 SC engine swaps. The end result delivers a 4.0 second Fiero. This service costs 10K. <snip>
Who exactly is this person? I ask because there have been issues with a certain person in the Dallas area you may want to research on here.
I can't remember his name. Talked to him about 3 years ago. I can't see spending 10k on a car only worth 3-5k. I've seen people selling Fiero's with 9800SC's already in them for about 7k. Even though 10k for a 4.0 second car of any kind is probably a good deal. I personally would probably kill myself in a car that fast the way i drive...
Back to the injector discussion, I have the new Accel injectors in the car now. The rail clips worked perfectly and everything is in place now with no leaks like I had with the Bosch series 3's.
Now the trouble is the car starts real nice for about 1 second then shuts out. It's like it's not getting any fuel. To back up, I just installed a new aluminum fuel tank, new fuel pump, the new stainless fuel lines from Fiero Store. The car sat a few years out of gas and the tank and lines rusted. I literally just replaced the entire fuel system. When I turn the key I can hear the fuel pump kick on and pressurize the system. When I had the Bosch injectors in that were too short, at this point fuel would pour out all around the top of the injectors. This tells me I have the power to the fuel pump wired correct. The fuel gauge shows me at about 1/3 tank which tells me I wired the sender correctly as well. This is all a miracle as the new wiring is completely non-standard. I know fuel is reaching the rail as it was flowing out of the incorrect injectors. Maybe the pressure isn't enough. I am not sure. Any ideas as to what I should try next? I have been pondering the purchase of the fuel pressure gauge from the Fiero Store so I will at least know if I am getting the fuel I need to run and operate the new 17lb Accel injectors I just purchased. Feedback would be appreciated. I am lost as to what to try next...
Try checking your ECM trouble codes. Does it flash 12? Your description sounds like the situation described in another thread. The ignition module fires the engine initially then transfers control to the ECM which, if bad, immediately causes the car to die. Does it always act the same way no matter what you do with the throttle?
Check the Denso 941 injectors. Any injector rebuilder should be able to give you the dimensions on them. If they are long enough, you don't need the clips. The Denso's are also pintle injectors and you can get them in 15, 17 and 10 lb ratings. Check with Fuel Injector Connection. Email John and ask him for Fiero pintle injectors.
BTW, is that actually a 9800SC or a 3800SC you've referred to?
[This message has been edited by fierofool (edited 07-03-2013).]
Hudini, thanks for the tip. The Service Engine light is now on. I can't drive it to Auto Zone to have them read it. Isn't there a cryptic way to manually read it? I think I remember seeing that somewhere years ago...
Since it kicks on right away, I'm hopeful the injectors are fine.
Yep, I was probably remembering the 3800SC engine and pulled 9800 out of my overloaded brain. Basically it was the Grand National engine swap that everyone seems to get the best performance out of. If I recall they even beat the V8 builds and you keep the all so useful trunk. lol
yes, even changing the throttle has no effect at all whatsoever. It runs longer if I blast started fluid into the intake manifold... This tells me the spark and everything else is fine. It's a fuel delivery issue which really pisses me off since I have replaced almost every piece along the way. I'm into this about $1,000.00 so far and still no running car...
Go to the main page on PFF and read how to pull codes. The SES light should always be on when the key is ON and the engine is not running. Also, make sure both injector fuses are good.