Please help

[ccordell]

Ok I sunck my b2 in a river edge and had to change the motor out. I went back with a 2.9 out of a 90 ranger. This motor had no egr valve. And my harness has another plug that goes down the driver side of motor toward the bottom. This motor has nowhere for it to plug in. Now I have this motor where it will crank and run but after it gets good and warm it starts acting up and will die if I stop at red light and let of gas. It is also getting bout 3 miles to the gallon now. What is my problem? Can anyone help me?

 

[adsm08]

To start, double posting this isn't going to get you help any faster.

I"ll be that the plug you are asking about is for the knock sensor. I think they moved them on the later versions of that engine.

The EGR is just a matter of swapping your upper intake so that you have an EGR port again.

As for 3 MPG, it's hard to say. There are lots of things that can go wrong on an engine swap. Many more so on a used engine. Check timing, check IAC check TFI module. That's where I'd start.

 

[ccordell]

Do would the knock sensor make it run rough like that. And where did they move them to. And you think I need to put an egr on this one to help it run better. I knocked some holes in my exhaust above my o2 could that have something to do with my problems also.

 

[adsm08]

I'm not sure where the knock sensor was moved to if it was at all on the later 2.9s. I haven't really pawed over any but my own 87.

Your computer expects to have the EGR valve and will run the engine accordingly, so yes, get it hooked up. It should help. Your exhaust holes and that unplugged sensor, what ever it may actually be, are also likely contributing. An unplugged knock sensor can cause some rough running too.

You always have to start by fixing the problems you know exist before you can start trying to diag another issue.

 

[ccordell]

OK thanks I will start with doing that and see what happens. Will post the update when I get those taking care of. Thanks for the info

 

[CountryBoy704]

seems like havin a hole above the o2 would really mess up with how it reads, might explain your mileage prob, is it running rich?

 

[kimcrwbr1]

Fix your exhaust leak and get a 90 computer and harness. The knock sensor tells the computer when to retard the timing without that and the egr plus the air getting sucked in the exhaust your computer probably went into limp mode just enough to get you home. I would just swap out the harness for that engine along with the computer then troubleshoot it from there. You cant troubleshoot something that will probably never work correct. Oh yea good luck finding a good knock sensor if you buy a new one and cant get it to work you will be pissed at the cost.

 

[kolton]

You hook up the plug wires correctly? Lol

When it dies does it chug for a second and then die or does it just all of a sudden shut off. Sounds like fuel to me. Electric pump or something. But you shouldn't be running 3mpg... Ever.

 

[ccordell]

Thanks everyone I have put 90 computer in wiring harness and all. I have took the gas tank off cleaned it blowed out gas lines put new injectors new fuel pump in tank and in line it has two. and new filters it has two of them as well. Plug wires are right and timing is set. The knock sensor is I dont know bout Im not a master mechanic by no means but I know that I have a plug hanging. And it does run slugish right before it dies. I did find my pvc valve the garmet and hose are sucking lot of air. Fount that today.

 

[ccordell]

And it is like it is loading up with gas. I drive it at 60 and out of the blue its like it just takes off.

 

[kimcrwbr1]

The only way to know for sure if the wiring is right would be to check every wire from the computer to the components the 1990 computer dont use a knock sensor and the only way to know would be to compare schematics I am almost sure the harness you are using is not correct for the 90 computer I am going to compare schematics and see if I see any issues.

 

[ccordell]

Thanks cause Im lost. I have done all I know to

 

[kimcrwbr1]

I dont believe they put the 2.9 in 1990 didnt they stop the 2.9 in 1989. The wiring is a little different between 87 to 89 in 90 they went to a different ignition on the 3.0.

 

[kimcrwbr1]

my bad i looked at my vacuum diagrams an it is the same for 89 and 90 but dont have the wiring for the 1990 2.9.

 

[ccordell]

ok thanks my 90 motor came out of ranger not bronco sorry should have said that. but I set both motors side by side before I put it in and everything was the same exccept the 90 didnt have the egr