1989 302 swap in 49 Ford F1 starts one day not the next

E-rok

Member
Feb 5, 2021
6
3
13
37
North Idaho
Hello all,

I have a 1949 Ford F1 with a lopo 302 from a 1989 crown vic with shorty headers and an Explorer intake manifold.

I am having a heck of a time getting this to run. I could not get it to start to set base idle this past month from what I thought was just being too cold. Then I realized that I did not have a ground from fire wall to engine. So on a "nice" 45 degree day this week, I added a ground from the ecu stud (firewall mounted) to the head. Truck started right up. Played with the timing a little and it was idling decent but not great, but would rev up great.

Fast forward to the next day, NOTHING. Just cranks with a minor stumble like it almost wants to try to fire up. I put in a new coil since who knows how old the original one was, no difference.

Fuel pressure is great, brand new inline 255 pump. I did obviously have to hack up the original harness to strip it down and admittedly there are some heat shrink but connectors in there. And all grounds were spliced into 1 big ground wire. I did forget to drill and tap for ACT sensor but I will be removing the manifold tonight to address that.

I am just stumped at this point, especially when I thought I had it sorted out when it ran good for 2 hours.

Thanks!

20210123_183444.jpg

20210123_183454.jpg
 
  • Sponsors(?)


StangNet created a new car social app called knowmoto! Add your Mustang or post a photo in the knowmoto app and enter for a chance at a $100 gift card from LMR. Click the LMR Logo for more about the knowmoto Mega Thread!

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,192
12,099
224
Massachusetts
I spy 19# injectors from the explorer.

what ECU are you using? The non-HO firing order is different from the 5.0 HO. The non-HO uses batch fire with 14# injectors. If you are using a HO ECU, its likely not liking the firing order.

do you know the 3- digit ECU code?
 

E-rok

Member
Feb 5, 2021
6
3
13
37
North Idaho
Thanks,

The photos are a little outdated, I did initially swap in the explorer injectors but I put the original injectors back in.

Donor car was an 89 crown vic so we used the ecu etc. I have it setup with non HO firing order. I do not know if it has anything to do with deleting all of the emissions (I used an EGR fooler plug).

I have since given up and will throw a carb on it next week, it is an old truck after all. Would have been cool to get the FI working.

I suspect my wiring has a mistake sonewhere and or just bad crimps.
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,192
12,099
224
Massachusetts
EDIT: misread your post

I'd say dump the EEC-IV codes before you throw in the towel. Make sure you pull the engine off, and engine running codes. I'd hate to see you ditch the EFI over something simple.
 

E-rok

Member
Feb 5, 2021
6
3
13
37
North Idaho
EDIT: misread your post

I'd say dump the EEC-IV codes before you throw in the towel. Make sure you pull the engine off, and engine running codes. I'd hate to see you ditch the EFI over something simple.

I pulled the lower manifold to drill and tap for the ACT sensor, and pulled the harness as well. So before I blow a bunch of money on carb stuff, I am going to go thru the harness one more time, possibly clean it up some more if I can, and try it once more.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
19,933
6,720
193
polk county florida
Yeah, not a good idea to gang them all together, the important ones are from negative batt cable to the (in your case the body) inner fender then it connects to that cylindrical connector in the harness below the solenoid (mustang configuration) the one in the injector harness to intake or block (I think that one is actually orange) and the one next to the computer itself, there is another from the back of the drivers head to the body but IIRC that is more for the instrument custer gauges
Veryuseful.com has some diagrams and pics that help.
 

Mustang5L5

Put lubricant all over the balls
Mod Dude
Feb 18, 2001
36,192
12,099
224
Massachusetts
Do you have any good pics of around the motor? Up close pics showing the wiring and sensors and such? I'm just wondering if anything sticks out like a sore thumb as being wrong.

The fact that it ran for a while and then didn't makes me wonder if this is a similar issue to the burnt pin 46 trace on the 5.0 HO ecus. I have no idea if the non-HO ecus are pinned the same.

For the hell of it, unplug the harness and test the pins on the ecu with a multimeter. Select continuity and probe pin 46 to both pin 40 and pin 60. You should have continuity IF, and only IF the ECU is wired like the Mustang ECU. I think the speed density batch fire ECU's are similar in how they run the grounds.

If it doesn't ring out that means two things. 1) the ECU is pinned completely different and none of this applies or 2) there was a wire harness mismatch which burned out an internal trace. #2 is something i'm not 100% sure on as my knowledge is mostly the 5.0 HO EFI setup and not the non-HO setups.
 
  • Like
Reactions: 1 user

E-rok

Member
Feb 5, 2021
6
3
13
37
North Idaho
I dont want to ghost this thread. I ended up just going carb. Looks a little better anyways being in an old truck. Thanks for the input all.
 

Attachments

  • 20210227_181207.jpg
    20210227_181207.jpg
    506.3 KB · Views: 18
  • Like
Reactions: 2 users

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
19,933
6,720
193
polk county florida
Looks good, nothing wrong here, now where did you put that blower?
That carb is way too close to that intake. A small blower makes a great carb spacer :nice: they are kinda scary to small children, I'd post a disclaimer.
Hows the rest of the truck coming along? Come on, we need to see this project through.