Just installed a new set of 21 lb injectors in a stock 5.0 in my 86 bird it has a rough idle at times an what's to die when I stop an put it in park any ideas on what I need to do to fix it or add to it oh an it don't drink the has it guzzles it an I need it for my daily driver so I need the fuel consumption to go down ALOT LOL
Is it a mass air car ? It needs a matching maf and if its not a mass air car bigger injectors will not work
Stock tells me that it's speed density which I'm guessing it still is. Go back and install 14lb injectors. You can't change them out (without chips and a tune). There's no reason to use larger on a stock motor.
injectors are way to big for the stock efi system
@stang8u
The car runs fine while driving its just when it's at a stop it may want to idle rough they work in the car
@seek
I was tring to get as close to stock as possible I tried looking up stock injector size online an all I could find was 20 lb injectors so I ordered 21 I still have the stock ones they only have 121000 miles on them but I have them I guess that will be next to clean an reinstall old injectors or have it tuned or find a chip for it
I really don't want to get into that upper intake again any ideas on were to look for a chip or who
makes one
Just a chip still won't work. A chip won't do diddly to a stock engine anyway, but that's not the point here.
The EEC is set to run on 14 lb./hour injectors. Also, changing injectors and/or a cam in a speed density engine is also a big no-no.
There's no magical fix for your problem, save going back to 14# injectors. That's a fact. I'm not trying to be a know it all, but a lot of us have been playing with these cars for a long time, and we know in our sleep what can be done and what can't.
It's true, it amy run rather well at speed, but, as you state, it idles like shiznit because the injectors flow more fuel than what the EEC's parameters are thinking are there. Hence, it runs pig rich.
With the car running, can you smell unburnt or raw fuel from the exhaust?
Don't believe us? Take it to a sniffer and see the amount of hydrocarbons from the tailpipe.
Want to make some power? Get some GT40 heads, an HO cam, and some good headers and exhaust. Throw that on, combined with an EEC (either speed density, or mass air, your choice) and then let the fun begin.
But....even on a newer 5.0, even with mass air, you can't just slap injectors in without also stepping up the Mass air meter. Everything has to work in conjunction with each other.
Good luck.
If it has the settings for the new injectors, it should be fine. Any settings can be overridden in the EECIV. It's pointless though.
IF something like that worked, it would be cost-prohibitive. There is nothing you could "buy" off the shelf. All you can do is find a tuner who will charge you by the hour to guess at the tune until it's right enough. They'd need a wideband sensor installed on your car, software that has a base tune to build from, and likely a dyno. I can't see anyone putting effort into such a feat since these are NOT mustang EECs without you spending thousands of dollars for no reason. Just stick the 14lb injectors back in. Why did you pull them in the first place?
Or; OP, find a wrecked Mustang with a good engine. Acquire said engine, and EEC. Install both into your car. Change fuel pump, and add necessary wire for mass air, if engine is not speed density.
There's a writeup on CoolCats.net about this, and so much more. Your car I take it is an '86, so it would be pretty much drop in and run, since your car is a 5.0, no wiring would need changed, unless the engine and eec are mass air.
Seek, I feel that with smaller throttlebody and E6 heads, even 19# injectors would be overkill for his engine...assuming a chip could fool the EEC into it. There's still a lot of fuel to account for. I don't think there's a workable way to do that, or else we would've known about it long ago....or else it's just so much easier to throw on E7 (at least) heads and toss in an HO cam. I don't know, but I have a feeling that with his injectors, unless he puts on better heads, an aftermarket cam, and at least an HO intake, he'll have problems with idling, fuel economy, and eventually plugged cats due to carbon buildup.
It's about akin to putting a 750 double pumper Holley on an old stock 5.0, and expecting it to run perfectly without putting smaller jets in...of course, what I know about carbs can be written on a flea's back.
I can see where the EEC would ground the higher-rate injectors for a shorter time, but as you state, it's not at all cost effective to tune the EEC for that. OP, there are literally tons of cars to get 14# injectors from. No rocket science to getting them, cleaning them, and reinstalling them. New pintle caps and o rings are available at any decent parts store, too.
keep us updated :)
@tbirdsport
Thanks for the advise I'm learning as I go on this ole car but now if I converted the car to mass air would that be enough just wondering thanks
@seek
I pulled them because the car has been setting for over 6 year it was my first car an I thought if I was going
To make I my daily drive I didn't need to go running after parts every weekend trying to keep it running
So I made one BIG order to summit racing I got new tires drums shoes shocks struts plugs wires "fuel pump an sending unit" (turned it that was my problem all along) INJECTORS new rotors pads an fuel filter some what starting at the ground an going up but u got to have good footing on the road or you'll just slide off the edges
I do have a HO intake upper an lower just no throttle body would that also help thanks
Simply put never just throw injectors in a car that are to big. 21 LB injectors are a bit to big. @200Hp and 80% DC with fuel pressure @40 LBS you should have a 16 LB injector. With that a 21 Lb injector at the same parameters can sustain 275 Hp.
Even a 19 LB injector is a bit big but workable to an extent. A 24 is a bit to big. Guys are getting in to the 325HP range with 24 injectors. Just saying!
Are your original injectors GREY?? If so they are in fact 14 LBS!!
The 1986-95 HO 302 Mustangs use a 19-pound injector.
The 1996-2003 4.6 SOHC Mustangs use a 19-pound injector.
The 1993-95 Cobra Mustangs use a 24-pound injector.
The 1996-2001 Cobra Mustangs use a 24-pound injector.
The 2003 Cobra Mustangs use a 39-pound injector.
The 1987 - 1988 TC uses a 35 LB injector
It's simple to change the injector settings if there is a base tune to go from. I know the things are way too big for the stock motor. He'd need a completely different engine to make use of 19+ lb injectors, but the functions in the EEC COULD be modified to work fine with the larger injectors. There is no way that it has any purpose though - even the stock injectors are fine for mild part swaps, and they don't require changing the EEC in any way.
From this entire thread, and confirmed a few posts down, he is fairly young and may not have the means to do a HO swap. I recommend installing HO parts (other than an intake) since we don't know his current mechanical level. He's looking to get the car running. 14lb injectors are the thing to use.
Also op, when my car was stock and had minor mods like the HO intake, I would average 22mpg taking suburban roads to college without either a heavy or light right foot. On the highway I'd get 30mpg, 34 after some mods. Since increasing my power, I'm down to like 18mpg on the same suburb route and my highway is right around 30-31. You should be able to get pretty good fuel economy if you just get the car running right, with stock parts.
Also, OP, if you're looking for some HO stuff, I have an intake, complete with 19# injectors, throttlebody, fuel rail, injector harness, etc.
I also have an EEC from a lincoln mark 7 (same as Mustang HO) that will work with the intake. All you'd need is an HO cam, and some heads, I think I have a set of decent E7s as well, but shipping them wouldn't be cost effective.
It's an option, if you're inclined.
If you were closer, I could help you put it on, and show you some stuff along the way.
I appreciate all the advice I'm just going to swap out the injectors an be done with it the ho swap would be nice but after just buy a house an with my boy turning one this next month I think I have things that come first
@ seek
What mods u run to get the 30+ mpg
At the time that I started monitoring this, I was on a stock motor with HO upper intake, and maybe throttle body. The motor was tired with over 200k miles and maintenance neglect (there was a 3/4-1 inch layer of hard carbon in the lifter valley when I took it apart). After I installed an electric fan, I saw a 1 to 1.5-ish mpg gain on the highway (average). There's a thread on here somewhere from my testing on that morning.
I think I was around 30mpg at 70-75mph and 32-33mpg at 60mph, then the electric fan got me up to 34.5mpg at 60mph (the testing was something like 30mpg one direction, 38mpg on the way back). My fuel economy on the highway didn't change much at all after rebuilding the motor and using gt40 heads, full exhaust, etc and a 4r70w. Going from 2.73 gears to 3.55 dropped me down to 26-27mph. Switching to 3.08s got me back to 30-31 and I got traction with stock sized tires on the 1-2 shift on summer days. I had to let up on the throttle to get traction back when I was using the 3.55's and hitting the 2nd gear shift. It wasn't the power or tires so much as it was due to me running aggressive transmission fluid pressures in my 4r70w transmission (and the additional gearing in 1st and 2nd over the AOD). Oh, I think bumping the tire pressure up to 40psi also helped me on those tires - it was likely around 1mpg on the highway. I was making a lot of 140-mile trips every weekend back then and using 4.1-4.3 gallons each way. I'd normally be between 4.2-4.3 gallons used at that point. I calculated my numbers off of a tripminder, which matched the fillup numbers. I used GPS data for the mileage as the car reads a bit low (by 4%). I have the "correct" speedo gear in there, but I just need to bump it up by the next size which will be slightly more accurate. Since I am no longer even close stock, the best way I can get close to my old numbers is by pulse and glide - allowing the car to accelerate in 4th gear, then letting off the gas completely. With my mods and tune, when I am over 30mph and the throttle is closed, the engine basically shuts off. This has allowed me to get close to 33mpg with my current parts, but it isn't really something that someone wants to do all the time unless they are a "hypermiler".
If you have the stock motor, I'd check to make sure that your oxygen sensors are good, you have good spark plugs, wires, coil, rotor cap, etc, have a good alignment. Check/replace wheel bearings, transmission fluid, and other drivetrain items. Something is really wrong somewhere if your motor is stock but you have trouble reaching at least 20 city/30 highway while not slamming down the gas pedal between every light. You will have a slightly higher aerodynamic disadvantage due to your non-aero frontend, but it shouldn't impact it TOO much.
Well I just replaced 85 % of the things u listed I still need the wheel bearings an o2 sencers but I like the idea of the HO intake I think that's what I'm going to do HO intake an stock injectors
An on a side not u have any Idea what makes the digital speedo to dim cuz I can just barely see it
Sitting on my shelf collecting dust??
(http://i740.photobucket.com/albums/xx46/proguns/001-104.jpg)
Keep your e6 heads, and throttle body, get a sd computer, 19/lb injectors, swap in a h.o cam, and have yourself a mock 86 mustang engine. When the car needs exhaust, throw on duels.
I'll bet this would get you 90% of what your looking for.
@Tom
Thanks for the offer but I already have a HO intake an yes they are grey injectors
But what year that intake come on? An what model thanks
Here a pix of the old bird I've owned it since I was 15 love this old car an hate to see what it's become since I let it set so long needs a lot of love but I hope to have her back showroom ready someday
The HO intake will certainly help all around with the stock longblock. You might also want to look into adjusting the tv cable and replacing the grommet that holds the thing in place. While more HO engine parts would help performance, getting the stock motor running well would need a better flowing intake at a minimum. Headers and exhaust would help a bit too, but they're more necessary with a HO swap.
If you're just looking for a good daily driver, the stock motor is fine. Adjusting the tv cable will change how the transmission shifts and provide more pressure, which may increase longevity at the expense of being a more harsh ride (shifts won't be as smooth). Allowing the engine to shift higher in the rpms by adjusting this also means that you need to get the engine breathing a bit higher up in the rpms, which the intake and exhaust help with. I'm also of the belief that a larger tb and removing the air silencer will do about all you need on the stock motor intake-wise. The power difference IS noticeable - I remember how nice it was that the car was just that much faster. When you're working with 150hp and 270ft/lbs, a small improvement makes a big difference, especially if you can get another 500rpms out of the shift points and motor.
So how's it running right now? The stock motor should be pretty smooth, yet responsive at throttle input. There shouldn't be any hiccups. Also the smog pump and pipes can just cause a ton of grief. They were a common failure according to the receipts I have of emissions-related work. I think the TAD solenoid caused me to have issues idling when the car was new to me also - the thing would just die. At that point I didn't know what I was doing with cars and had it towed.
At idle you have high vacuum so check for vacuum leaks. Also make sure the EGR is good (not leaking), along with intake-track gaskets. Have you pulled codes to see if it reports anything? Mine never lit a light, but codes were stored.
Looks like a 96-98 Explorer intake. It's extremely overkill for the stock t-bird motor. Vacuum would change quite drastically at tip-in throttle. They're good intakes for the stock HO motor, and ported they work well on a street motor with 300-400hp. I'm waiting to get one back from porting that I will use on my expected 360-380hp topend rebuild. Your car won't shift much more than around 4000 rpms so unless you want to change the entire engine down the road, your existing "HO" intake is fine.
Huh??? Vac changes in any intake at tip-in, I can guarantee a stock SO would run fine using the 14lb inj and 60-65mm TB... Would there be a increase in power??? Probably a little but so small that you'd have to imagine the increase...
I'd agree but the stock SO TB is only a asthmatic 50mm, the '86 HO used a 58mm TB and SO upper(at least the opening is smaller than a later HO)... With the half decent flowing Explorer intakes avail cheap, I wouldn't even consider a HO intake...
Got y'all a update reinstalled stock injectors an now it run like S**t an I can figure out why the service light comes on when I start it but goes off after like 20 mins an it idles funny any ideas fellas
An anyone know we're this grill come from is it factory or aftermarket thanks
I'm not saying it'll change much, but the larger chamber of vacuum would simply make changes in the throttle body pull in air much faster. I have no clue how miniscule this would change how the engine runs for that split second, but it'd an interesting thought. I love how much a simple sensor such as a MAF sensor makes life so much more predictable. The 60mm tb never hurt anything for me. I think the larger intake basically made the engine run closer to ideal when cold and under WOT. I have no idea what the stock EEC commands, but if it's anything like the mass air ones, it's 11.7:1 AFR. If the bigger intake track allows more air in than the EEC knows about, it will get closer to the ideal 12.5-13.0:1 AFR and make more power. I assume that is where most of the power gains come from by the swap on the stock motors. Changing how the AOD shifts with the tv cable and making more usable power up top is nice too. It would be interesting, but nothing more, to see a wideband and the changes it shows with a simple upper intake and tb change.
What rpm does your car want to idle at now and before the injector change? The extra (unmetered) fuel going in could have helped it run smoother by making up for air that is getting in some place else. It is difficult to troubleshoot without being there and seeing the engine in person. It could be a bad throttle position sensor giving you bogus throttle position readings, it could be the idle air control valve that is leaking or stuck open, it could be vacuum leaks, it could be a bap sensor telling the eec that you're at a higher elevation, it could be an air charge temperature sensor or coolant temperature sensors telling the eec that the engine is up to operating temperature, etc. It could be a bad fuel pressure regulator. It could simply be a bad connector in the wiring harness or badly clogged injectors. How old is the gas in the tank?
If check engine is coming on, you need to pull codes and see what it says. It sounds like something is bad that the eec relies on when the engine is cold. Codes, even with how few there are in the EEC-IV, are very helpful.
I just replaced all the vac lines an I'm not sure what it idled befor I installed the 21lb injectors the car an i have no idea what it idles at now dont have a tach on it, but the car hadn't been started in over 8 years I dropped the tank an installed new sending unit an replaced fuel filter oh an also cleaned tank an put fresh unethonal 93 octane fuel an it idled great but sucked way to much fuel but I think it's one of the sensors I got a friend who is going to check the codes but I believe I'm going to convert it to MAF I got a friend of is giving me two MAF computers an a MAF sensor all ill need is the wireing harness an install that HO intake
You may have a bad fuel pressure regulator, pull it's vac line to see if it's wet... If that's OK would be a good idea to check pressure...
BTW if the MAP sensor has vac or electrical issues, it'll run 3x pig rich...
Ok I'll try that
Before you ever change parts by guessing, always pull codes. That will help narrow down issues and make it easier to resolve those issues.
And your grille looks like it's one of the rare Motorsport parts...take care of it, those things just aren't very common.
Describe the idle, does it hunt, go up and down, or is really low, or fast? It's sort of uncommon for injectors to really be an issue, not saying it doesn't happen, but it's not the most usual thing.
Check codes, make sure your timing is set right (unplug the spout first, it's the grey plug-like thing in the TFI harness that goes to the distributor).
And, you haven't turned the stop screw on the throttle body have you? That will wreak havoc on the IAC's settings. Don't ask how I found THAT out, ages ago...
Ok the idle is choppy the motor shakes horrible even runing up the road I'm wondering if those big injectors messed up my fuel press regulator that what It seems to eather to be starving or running rich like it can seem to find its happy medium
Get the codes pulled. Anything that serious should show up in codes.You should perform both key on engine off (KOEO) and key on engine running (KOER) checks. There is a high likelihood that the problem will show up between a few codes.
The bigger injectors wouldn't do anything to the rest of the fuel system. Also, at idle if one injector was bad you would barely notice it. These things can run pretty smooth with 7 cylinders working, and they can still run but quite poor on 6 cylinders. The likelihood of having multiple injectors failing is very low. I'd stop looking at the injectors and check the fuel pressure AFTER pulling codes. I'm not sure parts stores will pull codes on an ODB1 vehicle so I'd find a code reader to use, or purchase one for $40.
Also, have you touched the distributor at all? Verify that the base timing is set to 10 degrees and that the spout connector is plugged in. Again, these would show up with the engine diagnostic tests. The computer knows what it expects to see, and it will tell you about anything that doesn't match its expectations. You may have even had codes that you didn't know about from before you stopped driving the car - there are a few common ones that won't impact drive-ability much until the parts begin to fail completely.
I also recommend pulling codes but it isn't going to tell you if you have a leaking FP regulator(at least not directly), or loss of vac to the MAP...
If it seems to be running poorly as in several cylinders misfiring, I'd be checking plugs and maybe wires to be sure they aren't crossed... If that's the case, a gun type thermometer will quickly tell you which cylinders are misfiring... Just aim at each exhaust runner on the manifolds... If there are some dead cylinders(temp will be far less) then you have issues with ign system or the injectors/wiring, maybe EEC...
Well I work all weekend so it will be Monday before I get to fool with the ole bird but ill keep y'all informed
All you need to pull codes is the car, a paper clip, and a $1 test light. It takes 5 minutes, and will give you a very good idea of things to check.
I would also recommend resetting the base idle after pulling codes if no ide related codes pop up.
First check for any vacuum leaks, then start the car. While its running, unplug the iac and turn down the throttle screw until its barely running. Plug iac back in, reset computer, or pull battery for 10 minutes. Done deal.
Do you have the plug wires set to an SO firing order, or are they set to an HO pattern?
If you have it firing 1-3-7-2-6-5-4-8, with the number 1 cylinder nearest your passenger headlight. then that will cause your idle problems.
The correct f/o for your engine will be 1-5-4-2-6-3-7-8.
Only the HO cam will change the firing order, and thusly those affected cylinder's plug wires must be rerouted.
Just throwing that out there.
Plug wires are set to SO firing order I'm going to have the codes pulled 2moro hopefully an I'm going to check for vac leaks
Ok check timing is dead on I almost think I have a stuck valve
Now on cold start it idles for about 3min an dies an its rough but once it warms up it idles like its got a mild cam u can hear an feel it an when driving once up to speed (once I get there) if I pull my foot off the gas u can hear something clanking like a tink. Tink tink but I put foot back on pedal an it goes away an it seems to be getting worst the more I drive it an I'm at the point were I'm just ready to do a complet rebuild any ideas
Yes, run codes.
Instead of guessing what the car wants, why not ask it?
Ok pulled codes one is
EGR sensor voltage is out of range
Running lean on bank one( don't know which side of Motor that is)
An a O2 sensor SS1
So that what I've come up with so far not really dug into it anymore
I think I'm going to take the cats off of it an replace the O2 sensor
I don't remember if you've said this, and I can't find it above. How does it idle when the engine is cold? If the problem is only when warm, o2 sensors would be likely but only for some time before the EEC marks that o2 sensor as bad and continues on in open loop (this would explain your fuel economy).
Have you ever touched the harnesses behind the intake? You don't happen to have the oxygen sensors plugged into the correct sides of the wire harness, do you? this would cause one bank to go lean and the other to go rich. The EEC is too dumb to correct them internally.
EGR also not working correctly could be flooding the motor with exhaust gases if it's stuck open, or if it is leaking and allowing outside air in. I'm not sure you can test this easily without a hand vacuum pump.
If your o2 sensor is shot, you can see if it runs any different by unplugging the o2's. This will automatically disable the adaptive fuel strategy on the computer and send factory tables in place of the o2's. If it runs better after, unlug the o2's one at a time and see which sensor is bad.
Tha car at cold idles horrible am will die if let to idle say to warm up before driving but after motor reaches temp car idles better but runs like its got a couple dead cylenders an which side is bank one?
o2 sensors are not functioning at cold start, not your problem...
Learn how to run the codes and do a cylinder balance test...
Didn't realize o2's weren't used for cold start. Ignore me.
So I need to see about replacing the egr sensor an go from there
OK if you think you have dead cylinders there is a scope that is built in to your BODY. It is called a WET INDEX FINGER. With the engine started from cold wet you finger and touch it on the exhaust manifold next to the cylinder it connects to. Have you ever seen a person check an IRON for heat. My MOM used to wet her finger and touch the IRON. It would SIZZLE and tell her the iron was hot enough. The same can be dun with an engine. If the exhaust outlet is cold that cylinder is dead. At the track away from my equipment this is how we would test for a dead cylinder. I use this technique all the time. It works and just do it correctly so you do not burn yourself. With that if you have dead cylinders you just might have a vacuum leak near those group of cylinders. If in fact the engine ran good before the swap you messed something up. Also to check for a vacuum leak i used to close off the choke on carb engines. This reduces the air entering the engine and if it has a leak it will smooth out quite a bit. On an EFI engine this can be accomplished the same way with your hand. Or spray some carb cleaner in the intake sparingly and see if the engine runs better. With that i think running codes is a good idea. But Ford says you need a worm engine to get proper results. other than TPS for example. Other than that check the EGR and see if it is stuck open or has an exhaust leak past the PINTLE. Good luck
O2 Sensors do not effect a cold engine. The engine is in OPEN LOOP on start up stratigies. The HEGO has to be wormed up before they start working. Then in closed loop they come in to play!!
:burnout:
Think I found the problem went an bout new egr sensor an as I went to take the old one off this is what I found (tried to post pic ) later but it only has one bolt holding it on
That would be a HUGE VACUUM LEAK!!!!!!!!!!!!!!! Do you think?????????????? :beatyoass:
Found IT
My EGR isn't even hooked up...no issues from it.
Does your car run better now?
The question now is the car fixed??????????? And who left the EGR LOOSE ???????????
Unless you TUNE OUT THE EGR removing one is not something i would do. The ECM strategies are programmed around it being working properly.
:shootheadCar runs a little better but still not right I'm just lost car still idels rough an driving it just does not run smooth at all thinking about changing the vac sensor for the EGR an see where that gets me any other ideas need this car running bad
You have an egr valve and a vacuum LINE going to it. EGR will play all kinda of havoc on idle, as will many vacuum leaks.
Did you pull the EGR valve off and replace the gasket? The gasket would likely be shot if it was like that for any amount of time. For a temporary solution, I've used a thin film of RTV on both sides and then reused the gasket. I only keep black RTV on hand as it should be used on some gaskets, but everything else I just make sure the surfaces are good and buy new gaskets. The EGR valve itself can also be bad. There can only be a small number of things that would be the issue. Verify no vacuum leaks, then you'd likely be looking at the EGR or sensors as being the problem. Other issues are far less likely to come up.
Replaced the sensor an EGR valve an all the gaskets on the egr an throttle body
Remove the EGR valve and clean off all the gasket material from both surfaces. Cut a piece of sheet metal to span the studs. Bolt it back and start the engine. If you still have issues which you still will this eliminates the EGR as a problem source. If it fixes the engine you found the issue. But my gut feeling is the EGR is not the issue. You can also check for a leaking EGR valve by feeling the pipe from the manifold to the valve. If it is hot with the Vacuum hose removed the valve is stuck open. This will mess up the running of the engine
Ok I'll try the sheet metal thing I'm thinking its the new vac lines I installed I didn't put clamps on them an the fit looser the the original ones
sry guys its been a few days an ive not got to work on the car but hoping to sometime today an thanks for all the advice on this project
Ok work on car an come up with nothing thought it was a bad plug (not)
Thought it could have Been a bad injector all read 14 oms Now I am lost all vac lines are good no leaks
Brand new egr valve an sensor and all new throttle body egr gaskets any other ideas really getting tired of throwing money at this. Car