351W swap

Topic: 351W swap (Read 2441 times) previous topic - next topic

351W swap

June 19, 2012, 10:28:17 PM

Neighbor has an 88bronco with original EFI 302 but he swapped in a 351.

I told him at the least to get the 351 EEC from the donor but he didnt.
He is also using his 302 harness and i also warned him it would be better if he got that as well but he didnt.

Need 351W EEC wiring diagram so i can help him swap pins on his EEC connector.

I told him that the injector is firing of fuel at all the wrong moments in time and at best we can get the EEC to fire the injectors in time wth the 351 cam to correct the firing order issue.

anyone got a 351EEC and 302EEC pin out for 88ford trucks?

Amazingly enough it starts fine, holds timing perfect, and really you cant hardly tell there is an issue.

Also i was amazed it is dumping codes
has 21, 33, 41 and 77 KOER. 21,33 KOEO.

I may be wrong, are the truck EEC's bank or batch fire?

going to therangerstation.com now to see what i can find.

he's really runing rich

he had a shop pull codes and they it would not dump any codes so i told my neighbor thats a sure sign there is an EEC issue, but i tried to pull them myself with a paper clip and they dumped out,,

anyone with 351 and 302 EEC pin outs , i appreciate the help.

351W swap

Reply #1 – June 19, 2012, 10:49:52 PM

nevermind, all the injectors are tied to pins 58 and 59,, stands to reason its called "EFI"
At best im gonna suggest he get the 351w eec,

351W swap

Reply #2 – June 19, 2012, 11:23:54 PM

http://oldfuelinjection.com/truckpinouts.html they also have bronco wiring diagrams. I didn't go through those.

It would appear to me that the wiring harness and pins should be identicle.

21 is ect voltage out of range (causes car to run rich.
33 egr not working, ignore
41 hego always lean, probably a bad sensor or wire, if there pluged in right

77, wot not present, operator error.

Basically, bad ect (engine coolant temp sensor) and bad o2 sensor, both could cause vehicle to run vry rich.

Sounds like it will run fine if these things are fixed.

351W swap

Reply #3 – June 19, 2012, 11:25:52 PM

Also, the computer sets the firing order, but where this appears to be batch fire, I doubt it will matter much. If it runs okay after those things are fixed, I think it will be fine.

351W swap

Reply #4 – June 20, 2012, 02:40:39 AM

wrong. cam sets firing order, the eec doesnt give 2 shiznits what the firing order is...and the truck 351w engines are HO firing order, but bank fire on the injectors.

351W swap

Reply #5 – June 20, 2012, 08:09:25 AM

I ment to say the eec fires the injectors by pin. On a batch fire, I really don't think it matters though because it fires all of the injectors on a single bank at the same time.

Also, I believe the 88 up 302's in trucks we're maf, so I think the computer would compensate for the extra air, and the o2's should compensate for the fuel mixture.

However, on a sefi system, two cylinders swap sides in the firing order, and will cause the computer to try to keep adding fuel to the wrong side.

I would personally try the 5.8 computer, if it were me, but I would probably see if the o2 code goes away when the ect is replaced.

351W swap

Reply #6 – June 20, 2012, 08:31:15 AM

truck does run, and pretty well
i thought the injectors had dedicated pins but not the case.

351W swap

Reply #7 – June 20, 2012, 01:09:26 PM

Quote from: Haystack;392831

I ment to say the eec fires the injectors by pin. On a batch fire, I really don't think it matters though because it fires all of the injectors on a single bank at the same time.

Also, I believe the 88 up 302's in trucks we're maf, so I think the computer would compensate for the extra air, and the o2's should compensate for the fuel mixture.

However, on a sefi system, two cylinders swap sides in the firing order, and will cause the computer to try to keep adding fuel to the wrong side.

I would personally try the 5.8 computer, if it were me, but I would probably see if the o2 code goes away when the ect is replaced.

No truck was maf until '94, mostly in California, and I think '95 were all mass air across the board..I can assure no '88 trucks, broncos etc were mass air, because I've had 2 '88 trucks, an '89, and a '92, and spent a good deal of time with a '93 and a '94, none of which had mass air.
I reiterate, the 5.8 truck engines were ALL HO firing order, the 5.0 engines weren't. They were all bank fire, meaning one side's injectors pulsed, then the other. Not sure when or even IF they were ever a "true" SEFI setup, as we'd know it, proper. And even if the cylinders somehow "managed" to..umm, swap sides....it's the EEC that ground the injectors causing them to squirt fuel, regardless. Considering that all four cylinders on a given side get their shots of fuel simultaneously, your statement makes no sense

With that said, I agree that a truck/bronco 5.8 eec needs to be swapped in, and codes pulled after a few start/run cycles are on the clock.

Quote

i thought the injectors had dedicated pins but not the case.

You might also dig around and see if there are diagrams on www.ford-trucks.com
Keep us posted! Be careful what year you get an eec from, as some of the later ones controlled the transmission...I'm not sure if they're compatible with an older truck, or even a manual trans...

351W swap

Reply #8 – June 20, 2012, 07:27:39 PM

Sorry, I thought the 88-94 5.0's were all mass air, my bad.

The 94 up 5.0 (all roller cam) trucks had the h.o./351 firing order. I delt with a couple of these at my work, and ASSumed that when the trucks got the e7's, they must have went to h.o. firing order too.

According to this chart of pinouts from ford fuel injection, the 86 up 5.0 trucks also used 19/ers instead of the 14# of the s.o. setups. It also lists the 89-95 bronco's, trucks and vans with the e4od as being mass air if you run over to the right of this chart.

http://oldfuelinjection.com/truckpinouts.html

And this link is what I based around the cylinderrs being on the wrong sde, even though it is a batch fire setup. It says you can swap injector pins, but the computer will adjust for air/fuel improperly.

http://oldfuelinjection.com/?p=92

A lot of what I was trying to say didn't make much sense the way I wrote it. Just didn't come acrossed right.

351W swap

Reply #9 – June 21, 2012, 01:38:38 AM

no biggie guys, i am suggesting he get the 351 eec for no real reason other than i would suspect the tables for injector pwm would be different but granted a lot of other eec tasks would be identical to the 302.

found his fuel pres bleeds down quickly when the key is turned off, this is not normal.
FPR holds vac on the diaphram so that mechanical ingredient works.
Has a tank and external rail pump with no evidence of leakage anywhere so i am suggesting he swap the FPR for general maint reasons but he may want to focus on the fuel pump in the tank and that short little 3'' line may have a crack in it.

this may answer the lean condition.

Also, he does not have the coffee can vac canister so he isnt able to store vac pressure at all. he found one and added it, this should aid in vac delivery to the FPR under certain RPM ranges as required.

personally, my nose and gut tell me he is runnng rich although the eec is not pointing me in that direction by way of codes.

351W swap

Reply #10 – June 21, 2012, 02:40:03 AM

X2 on FPR switch out...