Dosnt start only somtimes

[2lane]

I have a 86 Bronco ll. A few days ago I drove it to my friends house came out a few hours later and it wouldnt start. All it would do is turn over. Tried reseting the fuel switch still wouldnt start. Came back the next day and it fired right up. Now again today I drove it to work, back home for lunch then back to work with no issues. Went to leave work and all it does is turn over. I can hear the fuel pump coming on. Any ideas???

 

[TexCaliBII]

Sounds like the good ole TFI module on the distributor is one the way out. See numerous threads about it and I believe there is some info in the tech section as well.

 

[adsm08]

That sounds like what mine did for a while.

I never tracked down the actual issue, but I have some very strong suspicions about what it was.


Get a test light. Next time it doesn't start hook it between the positive battery terminal and the green wire at the ignition coil. If it flashes while you are cranking, the TFI is not the issue.

If it doesn't flash unhook the TFI and check for power on the red and blue wire (second up from the bottom I think). If that's good, probably a bad module.

 

[Jspafford]

Is it running rich? Flooding out maybe? Your mileage get worse all the sudden?

 

[2lane]

No its noting running rich or flooding.

 

[MLB]

I have an 88' that was doing the same thing that you have described, it was the FPR changed it out and it has run fine and started every time since.

 

[TexCaliBII]

Ah,
I did forget the FPR, yes it can do this too, and easier to change out too. Hope you get it figured out.