So it feels like something is going wrong with my injector circuit again...
Car: 88' GT V6 5spd
It all started a while back when one of my injector circuits started to fail. Fuse kept popping and I eventually traced it down to a bad injector. I bought a used set and of course out of all six only one was actually functioning. Anyways, I popped the new injector in and checked the other 5 and all was well for about a year or two....until last week that is....
fuse popped twice since then and the second time I only had a spare 10A that I shoved in there to get home. Now I have a new 5A back in there and so far it hasn't failed accept now I have noticed my fuel economy went in the toilet. Currently I am getting about 12mpg when I usually get about 20 so there has to be something wrong. HOWEVER, it has been unusually cold here in lately so I have been letting the car warm up for about 10min every day to and from work so even though I expected to loose a bit of fuel economy I felt like 12mpg is excessive. A couple times I felt a stutter in the peddle like the injector circuit was going to fail but it didn't.
My main concern is that one of the injectors fried and is either stuck open or something like that. My question is, if the injector DID fail, shouldn't my fuse continually pop? This is what happened last time I had this issue...basically as soon as I started the car the fuse would blow because one of the injectors was shorted but this isn't what is happening now. I don't want to go out and replace the whole bank because I feel like im just throwing good money at bad and those suckers are expensive. Even a used set is pricey and it clearly didn't solve the issue because its happening again OR maybe it was just a bad used injector? Either way I am not sure what I should do here. Also, is it possible that an injector can get stuck in an OPEN position? The car seems to idle and run okay...it doesn't seem like it has the same balls as it did before the whole issue started but then again it could all just be in my head too....
I don't know what your budget is but i just replaced them on my 86 GT and it was only $125, shipped from Rock Auto, it's the Standard brand on close out. They were the final item that got my car to run like it should again. I believe they have a screen inside them that obviously can become clogged over time not to mention just dirty in general. (not positive on the filter so don't slam me) I'd hate to think what a dealership would charge to replace the injectors on say my mom's cadillac but I'm pretty sure it wouldn't be anywhere close to $125, so it's all relative.
My main concern is that one of the injectors fried and is either stuck open or something like that. ......... Either way I am not sure what I should do here. Also, is it possible that an injector can get stuck in an OPEN position?
any advice fella's?
Pull the plugs, look at the insulators. If one is black, that cylinder is running rich.
If one is wet, that cylinder is flooded. To double check, put in a new set of plugs and drive long enough to give them some color then pull them. Look for a plug that still looks like new. -Paul
------------------ 1988 Fiero Formula 25k miles, garaged since 1988
[This message has been edited by Paul.S (edited 01-08-2015).]
Ya i was looking on rockauto last night and i saw that they have a couple "rebuild" options and the cheapest is about 18$ a pop but i have never heard of autoline injectors and the standards are almost 20$ each. I have used standard sensors in the past and it seems to be hit or miss. I have had mixed results with their products. Either way, I noticed that the car smelt like it was running rich this morning or almost like there was a gas leak but when I pulled away I looked to see if there was any gas leaks and it didn't look like there was so i think its just running rich. I gotta pull those plugs but its been in the single digits here in NJ this week and I dont know when its going to warm up some so I can work on the car. I dont have a garage or anything like that so we will see...maybe this weekend will warm up some and I can at least take a look then....
btw, does anyone recall which injector circuit is the front bank and which is the rear bank?
sorry gall, i PM'ed you instead of quoting haha anyways...my question was whether or not the cold start injector is part of the other two circuits that feed the front and back banks because it only seemed to be popping a fuse on the one circuit...
here is a test procedure that i found that i might use to check the CSI:
Bad fuel mileage may be totally separate from blowing a fuse. You may have a leaking injector or a bad coolant temp sensor that thinks your engine is cold all the time. As for blowing a fuse, here is an archived thread describing the circuit.
I have some used injectors I will sell for $30 shipped. I had to change my valve cover gaskets so I figured that they could probably use being replaced but once I got them out they were fine, I wasn't having any issues with them, I just did it because I didn't know any better. Here is the thread I posted earlier with some pics. They are a bit dirty.
A quick and easy way to determine which injectors aren't functioning, if you can get to them, is the "old long screwdriver to the ear trick" or the cheap Harbor Freight Stethoscope works well. You can clearly hear the pintle valves striking there seats. It just proves you have mechanical movement though.
Do this... Unplug your EGR solenoid. (It's the horizontal cylinder shaped thing, above the water pump. Has a 4 wire connector.) If the fuse quits blowing, put your original injectors back in. One of the INJ fuses also supplies the EGR. if the EGR solenoid shorts out, it can blow the fuse and kill half of your injectors. You will likely get a check engine light for the inop EGR, but this will help to determine if you, in fact, have a bad injector. I really doubt it.
Edit - for clarity.
[This message has been edited by Raydar (edited 01-08-2015).]
Do this... Unplug your EGR solenoid. (It's the horizontal cylinder shaped thing, above the water pump. Has a 4 wire connector.) If the fuse quits blowing, put your original injectors back in. One of the INJ fuses also supplies the EGR. if the EGR solenoid shorts out, it can blow the fuse and kill half of your injectors. You will likely get a check engine light for the inop EGR, but this will help to determine if you, in fact, have a bad injector. I really doubt it.
Edit - for clarity.
Thanks for the heads up on the solenoid but i replaced it last year and have had no codes or anything since so im fairly certain its okay. Not to mention the last time this was happening I had the old solenoid so place so I dont think thats the issue. But thanks for all the info guys i went ahead and ordered a set off RockAuto. I figured it couldn't hurt to replace them at 19$/piece. I am aware that it may not fix the issue but at this point the car hasnt blown a fuse in over two weeks.
Dan
[This message has been edited by Axl_Rose (edited 01-09-2015).]
Bad fuel mileage may be totally separate from blowing a fuse. You may have a leaking injector or a bad coolant temp sensor that thinks your engine is cold all the time. As for blowing a fuse, here is an archived thread describing the circuit.
Thanks, all sensors are new or have been replaced in the past few years so i am doubtful that it has anything to do with that. Plus, I plugged in WINALDL and the temp sensor was reading back accurate readings so that kind of confirms that the sensor is okay. And the bad fuel mileage started AFTER my fuse popped twice which is why i would think they are directly related. Thanks for the link it was very helpful =)
I took out the old injectors and cleaned the rail and to my surprise they all "clicked" when I supplied a 9V source to them, HOWEVER, here are the resistance values measured from all six that were pulled (in no particular order. Displayed in Ohms):
16.6 6.4 12.6 10.8 8.4 3.3 - I was shocked that this one even worked!
So with the new Standard(brand) Injectors in, the car idles like it has never idled before! Silky smooth idle and crisp throttle response and I can honestly say it was worth every cent of the $120. That last injector was probably what was shorting out that bank seeing as the impedance was so low and probably started to ground through the casing when it got hot enough. I was also surprised that out of the six, only 2 are even close to spec. I heard that spec is somewhere around 10-12 ohms? Can anyone confirm this? Also, does anyone here make new injector harnesses? My injector harness is so ridged im surprised the wires didn't snap in half when I was handling them.
Anyways, thanks for all your help fellas! The final test will be if my gas mileage returns or not.
The '86 FSM on page 6E3-A-21, recommends to replace any injector that measures 10 ohms or less. (thanks to Bloozeberry)
Your car must have overheated in the past....cooking both your harness and the injectors.
Thanks for the info. Although there is no other signs that the car was overheated. In fact, when i got the car it would never even get up to operating temp due to a faulty kinked thermostat. Either way, the car is running great now.
i am wanting to replace my injectors too. can you please give me the part # or send me the exact injector that you purchased from rock auto? also, did you get 7 of them and is the 7th (cold start injector) the same as the others? thanks!
i am wanting to replace my injectors too. can you please give me the part # or send me the exact injector that you purchased from rock auto? also, did you get 7 of them and is the 7th (cold start injector) the same as the others? thanks!
I am pretty certain the cold start injector is completely different BC It is supposed to have a bi-metal switch that only opens under -5*F but don't quote me on that. The injectors I ordered are Stanford part number FJ9. There is also another part number by Stanford that would work which is FJ27. The two part numbers are interchangeable but I wouldn't mix and match. I think the main reason for this is due to the fact that there were two diff types of injectors used on the v6 fiero's.
If you search cold start injector you will prob find many other threads on it
