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Discussion Starter · #1 ·
Hello everyone I'm in serious need of some help here, I have a 1987 Ford Bronco II. I dropped a used 2.9L V6 from a 1990 Bronco II in it. When i got it running I was having idling issues and did a lot of starting and killing it and over amd over whilst tryna fix the idle. Well I turned it over a few days ago and it started as usual, but then when I killed it moments later and went to start it again, no power. I lost all spark. I proceeded to get a new coil and an ICM, that gave me my spark back and I now have spark to my plugs, BUT, I do not have fuel even tho the pumps are brand new. (She doesn't bump either when I shoot fuel down the intake, it just spits it out) does anyone know what's going on??
 

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Discussion Starter · #3 ·
Puking fuel back out the intake while cranking is a good sign the ignition timing is not right.

Not to belabor the point but there is a young fellow that works at OReillys a few miles from my house that put a 460 in his Bronco II, it sure solved the power problems.

Bogie
I definitely believe the ignition timing is off, im currently working on getting that straightened out so we'll see what happens afterwards. Have you any idea why I still have no power to the pumps? (Keep in mind i replaced ICM and coil and now have power to spark plugs) maybe a wiring issue with the fuel relay?
 

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Discussion Starter · #8 ·
The fuel pump rollover switch (Pendulum) is located on the passengers side firewall. This switch senses any strong impact to the vehicle or senses to high a side angle and it will trip. When it trips it interrupts the main power to the fuel pumps! if that is tripped there is a pushbutton on the switch to reset it. If the switch was bumped hard or removed or tilted during ECU removal and replacement it could have been tripped as it is in the same proximity of the ECU. A good check to see if the thing is tripped is to shut off ignition and then turn the ignition on and listen for the pumps to run for 2 seconds as they prime the injectors. With engine not running the fuel pumps will not run. The fuel pumps need to see a RPM signal and sometimes oil pressure signal to kick them on after the engine fires. The ECU supplies the "Pumps On" voltage and can also be measured with a DVM as a positive voltage indication for about 2 seconds when measured at the pump of at the Pendulum.

On timing the engine there is a plug on the harness near the rear of the intake and it is called SPOUT plug. That has to be removed before you attempt to time the engine. If that plug is left in when you time it you will be way off...

Your sudden NO Start sounds to me like a typical failure of what is called the TFI block on the outside of the distributor it is a rectangular block of Usually gray plastic that has a harness connector attached to it. It's typical symptoms is good spark when cold then after a short time it heats up and no spark till it cools off again. I have seen a million of them fail..

Now about a crappy idle, the idle air controller is a cylindrical device bolted to the side of the upper intake and has a small connector going to it. this device controls the amount of atmospheric air let into the intake to raise and lower the engine RPM. a lot of people try to control the idle by twisting the screw at the throttle body. That is incorrect!!! Idle is controlled by the ECU and it takes signals from engine temperature, RPM, map sensor, etc. to calculate how long a pulse to pulse the injectors to get the recommended amount of fuel in the cylinder at the right moment. What typically happens to an IAC is it gets gummed up and dirty. and does not flow the correct amount of air the computer calculated it should hence wrong mixture for idle. There are procedures to clean the IAC.

Now here is where I ask you if you have dumped the codes from the computer to see if you have any hard fails. I also will tell you that to trouble shoot this little motor you need to know exactally what you are looking for so in that point I can not recommend enough that you get a manual on the ranger or bronco ii and read about how to set the timing correctly and all of the little quirks of the Cologne 2.9 ford motor If you can't afford a manual head to your local city or county library and check one out. If ya follow the manual you should be golden.. Good luck!:cool:
Thank you for that wonderful answer and informative reply man. I did in fact replace the ICM (Ignition control module) the little grey thing on the distributor. Going back to the beginning, I had spark, was turning it over a lot to try and fix the idle, then lost spark again. I then replaced the ICM and coil, then got spark back, but then lost it yet again after a few cranks and haven't had one since. I'm not sure what's causing this electrical malfunction but its major enough to kill all the spark even after replacing part. Also, I figured out my idle problem, the spring on the throttle cable was bad and forcing it in an open position. (Fixed)
 

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Discussion Starter · #9 ·
Rip VW Bravo on that explanation! you have demonstrated a fantastic willingness to help out and that is what we are all here for! My hat is off to you! Now I am gonna give some advice that sounds so off the wall you might never follow it
however I know it to work. The idle air controller accumulates carbon as milage occurs and my only explanation is that the computer compensates for the build-up and then the battery dies or you disconnect power to change engines anyhow the loss of power wipes out the memory and now the computer is no longer compensating for the carbon accumulated and its hard to get a good idle. I pull off the hose to the throttle body (from the air cleaner) and clean out the throttle body with a carburetor cleaner be sure to get in proximity of the Idle air controller it has a hole that goes to the spool valve it controls.I usually use most of the can of carb cleaner and you will have to work the throttle to keep the engine going but once you are done it's back to a workable idle. best of luck and keep us posted !!!

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Thank you sir, I did indeed figure out my idle issue, it was a simple spring on the throttle cable that was forcing the throttle in an open position haha I fixed it but still no spark :/
 
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