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Topic: Proper injectors for stock Speed Density 5.0 (Read 1464 times) previous topic - next topic

Proper injectors for stock Speed Density 5.0

My car has been diagnosed as having a bad set of injectors, and it runs poorly. SOME of the injectors, at some pont in the cars life, have been replaced with ones that have a different housing.  I look at the parts store/rockauto, and there are numerous part #'s and slight variations in injector styles.  How am I to figure out what part # is correct for my motor?  From what I understand, injectors are very specific and it is crucial to the vehicle's performance that they be matched to the computer.
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 3.8 V6 - Rescue
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 5.0 V8 - Survivor

Re: Proper injectors for stock Speed Density 5.0

Reply #1
Assuming the diagnosis of bad injectors is correct, and the car you are referring to is the 1988 Cougar 5.0 in your sig, the stock injector is the old Bosch style EV1 14 lb/hr injector, usually gray in color at the top where it plugs in. I don't have the original part #, but its probably obsolete/discontinued anyhow. This link to equivalent replacements for sale at Amazon may have some additional part # info or reference:

https://www.amazon.com/MOSTPLUS-14LB-Injectors-F47E-A2E-0280150710/dp/B07PMVV9JM/ref=sr_1_2?dchild=1&keywords=14+lb+injectors+ford&qid=1596404733&s=automotive&sr=1-2

Not to undermine whoever diagnosed the bad injectors, but I'd also have them check all engine vacuum lines, especially ones under the upper intake plenum going to the fuel vapor charcoal cannister, the map sensor, the pcv valve, etc. The speed density system is sensitive to vacuum leaks, and the rubber lines under the upper plenum are highly prone to aging cracks/leaks, which will cause extremely poor driveability/idle.

An HO conversion might be an option too, Cool Cats website has a write up on whats involved with that if you are interested.

Re: Proper injectors for stock Speed Density 5.0

Reply #2
Yes, I plan to do an entire GT-40 intake swap in the near future, and talk to BBK about a setup for uprated injectors, MAF, fuel rails, etc, and a mass air conversion.  But since, with my current list of projects, that may be a little while longer than anticipated, i just want to get it to run properly as is for the time being.  I'll check the vacuum lines as well for damages.
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 3.8 V6 - Rescue
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 5.0 V8 - Survivor

Re: Proper injectors for stock Speed Density 5.0

Reply #3
https://www.rockauto.com/en/catalog/mercury,1988,cougar,5.0l+302cid+v8,1198605,fuel+&+air,fuel+injector,6224

so all these injectors, with a whole list of compatable part numbers on some, all seem to have the same body style.  I would be inclined to believe that they are all the same, just from different manufacturers, but i notice that several are from the same company, but with different part numbers themselves.  Also, the ones listed on the site seem to be from an 'E' series of part numbers, while the one you showed me covers an 'F' series.  Am I overthinking this?  or are there valid small differences?
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 3.8 V6 - Rescue
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 5.0 V8 - Survivor

Re: Proper injectors for stock Speed Density 5.0

Reply #4
14lb EV1 style injectors are stock on a 86-88 5.0 Thunderbird/Cougar. Don't even worry about larger injectors till you have a HO cam and MAF.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Re: Proper injectors for stock Speed Density 5.0

Reply #5
https://www.rockauto.com/en/catalog/mercury,1988,cougar,5.0l+302cid+v8,1198605,fuel+&+air,fuel+injector,6224

so all these injectors, with a whole list of compatable part numbers on some, all seem to have the same body style.  I would be inclined to believe that they are all the same, just from different manufacturers, but i notice that several are from the same company, but with different part numbers themselves.  Also, the ones listed on the site seem to be from an 'E' series of part numbers, while the one you showed me covers an 'F' series.  Am I overthinking this?  or are there valid small differences?

Not really, the differences in part # or application probably stems from the fact that Ford used your 5.0 fuel injected standard output, or SO, engine in multiple vehicles over the years throughout the 80's and 90's.  Everything from Lincoln Town Cars to lowly E150 work vans. Same fuel injector, same basic fuel system in operation, just packaged slightly differently since a van has a different engine bay than a Crown Vic.

The important thing would be to ensure that you get ones rated at the 14 lb/hr rating because your engine computer is using that assumed fuel flow rating across the injector. Make sure any injectors you get have new  O-rings and lube them while installing, engine fires are no bueno.

 

Re: Proper injectors for stock Speed Density 5.0

Reply #6
I replaced the injectors over the winter, just started really driving it now that the weather is better.  The bucking and hesitation is GONE, and I have great throttle response.  BUT, now I have a serious idle surge problem.  I checked the EGR and EGR solenoid for issues, they were both fine.  I replaced the TPS and followed the idle reset procedure to properly calibrate it, no change.  I made sure the timing was still set at factory recommendation.  I checked for vacuum leaks/breaks.  Engine light is NOT on. 

I should add, while I had the intake off to change the injectors, I also deleted the smog pump, but NOT the egr.  I don't know if this would cause idle issues.  I DID leave the smog solenoids connected to the harness to avoid an engine light.

Also, I made sure I bought 14LB injectors, under your advisement.  I bought F47E-A2E replacements, 'Check fit' menu said it was correct for 1988 cougar, and description said it fits ford 5.0.  BUT, the injectors I removed, 6 of them were stamped E67E-B4B, and the other 2 were a different style/housing, part number suggested they were for a Jaguar...

Did I put the wrong injectors in?  Did I ruin the Idle fuel/air ratio removing the smog tube?  Or is there something else I need to look into?  I'm very happy i have driveability back; the car does perform better, but it is bothersome having to rev it up at stop lights, and sometimes it takes 2 tries to start it up now.
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 3.8 V6 - Rescue
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 5.0 V8 - Survivor

Re: Proper injectors for stock Speed Density 5.0

Reply #7
2 times to start.

I would check the fuel pressure.  May have a pump going out.

If you bought all 8 injectors of the 14lbs, you did correct. Dont worry about what you pulled out.
Mike

 

Re: Proper injectors for stock Speed Density 5.0

Reply #8
Fuel pump is a great place to start and frankly you will need more pump when you do the HO swap (minimum 19 lb/hr injectors and most run 24's or 30's) with a calibrated MAF or a chip so if you replace it I would go with a minimum of a 190 lph unit now and put an adjustable FPR on as well to get the pressure dialed in.

When is the last time you checked the distributor cap and rotor, plug wires, and plugs?  May just need a simple tune up but you can inspect these things and it should be pretty obvious if they need to be replaced.  Check the gap on the plugs and I only say this due to the mix and match on the injectors leads me to believe that other things on the car may have been haphazardly changed or poorly executed.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Re: Proper injectors for stock Speed Density 5.0

Reply #9
Ran test, delayed because the fuel pressure gauge I was using malfunctioned, had to wait for a new one to be ordered.  19.5 psi on ignition, 32psi at idle, spikes to 34psi at 2000rpm, then returns immediately to 30, and idling with the regulator vacuum line unplugged, its at 40PSI.  Mustang forums seem to idicate that this is okay, but my haynes manual says i should be looking at 40 PSI, even though it does not state under what circumstances that PSI should be had.
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 3.8 V6 - Rescue
1988 Cougar LS - Cinnabar/Rose Quartz Metallic two tone - 5.0 V8 - Survivor