89 bronco II

Ask technical questions about your Ford Bronco II here. Technical write-ups on your axle swaps, engine swaps, chop tops, etc. are encouraged.
Frustrated+
Posts: 3
Joined: Thu Apr 27, 2017 2:55 pm
Location: omaha,ne

89 bronco II

Postby Frustrated+ » Thu Apr 27, 2017 3:21 pm

I have a bronco that will start off running like a champ for about 4 miles then even though foot still on gas peddle it starts to loose power backing off from 60mph to about 35, no matter how floored I have it, it will not increase in speed. New ignition module, distributer, cap and rotor wires, plugs, throttle body sensor, map sensor, heat sensor, air flow sensor, doesn't have an Egr valve, new gas tank, fuel pump, fuel filter, relays(fuel pump can't think of one next to it). Oil gauge constantly goes from high to low while driving, can an oil pump cause this problem? About 1/2 year put in an additive to clean fuel injectors checked oil about a month later it came out thicker than molasses, quickly changed it but this slowing problem was already present. Can anyone tell me what's up with her??? Cylinders all check out as being functional, fuel pressure is up to par. HELP I love my Bronco II.

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tekatlarge
Posts: 945
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: 89 bronco II

Postby tekatlarge » Wed May 03, 2017 7:08 pm

Have you checked the computer codes? That would be a first start. What did you actually measure for a fuel pressure? Has this rig sat much?

get back to us with the answers and maybe we can fix you up. :cool:
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

Frustrated+
Posts: 3
Joined: Thu Apr 27, 2017 2:55 pm
Location: omaha,ne

Re: 89 bronco II

Postby Frustrated+ » Thu May 04, 2017 6:09 am

The only codes that came up was Ego and I thought that meant Egr but found out I don't have an Egr valve. For fuel pressure it started at 40 and slowly went down to about 35 and held.

Frustrated+
Posts: 3
Joined: Thu Apr 27, 2017 2:55 pm
Location: omaha,ne

Re: 89 bronco II

Postby Frustrated+ » Thu May 04, 2017 6:11 am

This is my daily driver , so she doesn't sit all that much, even now for the last 3 years have had a job only 12 mi away so as not to tax her. I get home and stay till next day.

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tekatlarge
Posts: 945
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: 89 bronco II

Postby tekatlarge » Thu May 04, 2017 5:08 pm

That fuel pressure is actually low from what I normally see IIRC it is supposed to be 40. and steady. When you unplug the vacuum line that goes to the fuel pressure regulator what change if any do you see? It should be rock steady. BTW look at the end of the vacuum line where it attaches to the regulator and make sure no fuel is present, If you have fuel at the vacuum port the regulator is gone.
If you happen to have a Vacuum pump hand held you can attach it to the fuel pressure regulator and put a vacuum on the regulator and watch to see if fuel pressure varies when you change the vacuum.

To me my gut feeling is you have a fuel delivery problem You said you replaced the fuel filter. There is another little device in the fuel system called a fuel accumulator. This device looks like a fuel filter on the line but it it Not. It is basically a little reservoir that holds fuel so the EFI won't starve out of fuel if your pump in the tank should be momentarily un ported it keeps fuel fed to the injectors to allow the pump to recover. It is a short amount of time it takes but it is important. The older ones you could actually take apart and they had a filter screen that would get mucked up but the newer ones I see now are sealed units. If this fails to allow enough fuel through it will cause the vehicle to lose power and the fuel pressure will drop and not be getting enough pressure the injectors need.

So look underneath I have seen them along the frame underneath disconnect it and check to see it is not blocked. While you are at it blow some air back through the fuel line to the tank to make sure it is not blocked.
One last check and that the fuel cap allows air into but not out of the tank.

Good luck.. :cool:
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

drofman
Posts: 470
Joined: Sun Dec 27, 2009 9:36 am
Location: san dirgo

Re: 89 bronco II

Postby drofman » Sun May 07, 2017 4:00 pm

Does it sound like a vacuum cleaner when you drive it? Plugged exhaust maybe? I like where Tek is going, maybe drive it with fuel pressure gauge on it to rule that out.

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tekatlarge
Posts: 945
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: 89 bronco II

Postby tekatlarge » Thu May 11, 2017 1:21 pm

Hey Drof whats up? Been doing anything fun? I haven't done a lot lately. Still working on my TCoupe project. It is coming along slow but it is moving slowly forward. It is going to be dealt a big blow come mid June. I have to take a little hospital time and have my right shoulder re-placed. It really sucks getting old! There is a 3 to 4 month plus recovery time. Thank god I am proficient shooting left handed. I I can entertain myself shootin all them varmints in the woods here or any other varmit that darkens the doorway.

I still keep my eye out for a BII to stuff my 2.9 in but so far haven't found "The One" There is though, a Exploder Sport just down the back trail from the homestead a few. I might stop by one day and see what his plan for it.. :cool:
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

drofman
Posts: 470
Joined: Sun Dec 27, 2009 9:36 am
Location: san dirgo

Re: 89 bronco II

Postby drofman » Fri May 12, 2017 9:54 pm

Hey Tek, Yep did a 5 day on the trail run in Death Valley the 1st week in April. Started in Beatty, NV and ended up at Lone Pine, CA. Took the F150 but missed the B2 a lot. Next year we are going to do the Mojave Road again. Ya my Dad used to say getting old is not for sissy's. I had my right shoulder rebuilt 4 years ago and so far all my other pieces are doing fine. Be safe and well my friend.

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tekatlarge
Posts: 945
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: 89 bronco II

Postby tekatlarge » Wed Jun 07, 2017 8:34 pm

Yes gettin old is not for the faint of heart..I just finished 7 days post op from a complete shoulder replacement! No fun but it gets better each day.. All these pills, 1 for up, 1 for Down, 1 for Left, 1 for Right, and a hand full more just to feel right...I like the little ones.

Of here come the nurses with butterfly nets. :cool:
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?


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