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Discussion Starter #1
Hey yall, new to the boards, i have an 86 bronco 302 efi, i had bad compression in 3 of the cylinders, so i got a fresh engine, and right as i get ready to fire i have no power to my starter relay, and figured out that the ignition switch does have power particularly the red and blue wire, and has power to the nuetral saftey switch as well, but not to the distributor or solenoid, so i bypassed the the safety switch and got power to both the objects just for the sake of spinning the motor. i also made sure everything els has power and it does, now we are at the point of we have spark, fuel and a fresh rebuilt motor and can only get it to spit and sputter, and no timing is not the issue, acts like it wants to start but just wont catch fire... i just want to get a fresh head on this see if anybody has any bright ideas. thank you

Branden
 

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double check your distributor timing, and your plug wiring. i just did a swap in my bronco as well, and had the same issue till i realized i had the plug wires set up for a 351. might want to make sure all the harnesses in the engine compartment are seated as well.
 

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Discussion Starter #4
thank you ... i am leaning to a wiring issue, plug wiring is correct. kinda thinking a ground issue or something with the cpu.... i do have power everywhere it needs to be... we tried scanning it for grins and it would not even scan. just kept telling me to turn ignition off while i was holding my keys in my hand
 

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does an 86 need a CPU to fire?
 

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If it's EFI it does have an EEC-IV.
 

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Discussion Starter #8
thank you for all the help guys. that isa great write up.... hoping to make some head way on it today.....gettin real sick of this, sucks i was able to drive it into my shop and now its pulling this crap.
 

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Discussion Starter #9
well i have been working on it for a couple days now, and everybody i am getting to come and have a fresh head tell me the same thing.... throw a carb on it and be done with it, kinda starting to lean that way myself i know its not too much work although i have never done it before...other than an intake carb dist. coil and modifying the throttle what els is there? should it be a mech. choke or electric choke. and what do i do with the tv linkage?
 

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Discussion Starter #11
update....i had another mech. look at it, told me that to have a good basis of where to start is to get a wiring harness in good shape. so i got a wiring harness in good shape, re wrapped it and put it took care of my grounding out problems and all the other electrical issues i was having. now the truck stumbles when i start cranking and want to catch but just wont kick. if you read earlier in the post you can get an idea whats going on. cause i am bout to take it out the the field and use it as target practice.
 

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First go back and make sure you "stabbed" the distributor correctly......you need to bring the #1 piston to BTDC it's highest point before it crosses over heading downward and in order to do this correctly take out all the plugs and placing a torque wrench and 15/16 socket and drive on the crank bolt, finger on the the #1 plug hole, turn the engine by hand until you get a "good push" of air indicating the piston is at it's highest point, set the harmonic balancer to 0 (zero) on the timing mark, drop in the distributor and rotate the rotor CCW until it points to the #1 lead on the distributor cap, mine points to 1 o'clock on the cap, mark for reference then put in all the plugs and wire it up. The fring order is in the Haynes Manual.......

Once it fires, warm up to normal operating temp, shut off and unplug the spOUT = spark out put connector located up near the distributor and set the timing to OEM 10 degrees BTDC re-connect the spout and drive it around.....

Any issues now that come up, pull codes from the PCM = power control module the vehicle computer and see if any "fault codes" are indicated and diagnose from there and get it dialed in.....perform KOEO and KOER if necessary.....this requires an OBD-1 Ford Code Reader with diagnostic book, costs $29.99 at O"Reillys..it just plugs into the OEM test connectors located on the right inside fender behind the battery area off the harness and for How To: www.forfuelinjection.com....all the info you need is there FREE....There is a"pulsing" technique for pulling codes but IMO it's PITA.......

You really don't want to go from EFI to Carb......you will regret it.......LEARN the EFI SYSTEM it's not that hard...and once you master it you'll like it....

Good Luck ~
 

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Discussion Starter #14
i dont want to go to carb i know.... i do understand the efi system. i have found tdc many times and tried to fire it. my rotor point to 1 o clock as well. next i need to start takin voltage readings and resistance readings. cause we have check and rechecked everything bout 10 times and still no result. i will let yall know what it is if it ever does fire
 

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you said you drove it into your shop was it with this engine or your old one?if you replaced your engine and it did this then are you sure your timing marks on your cam and crank gears are lined up right?they could be off and your rotor and everything will still line up.
 

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Discussion Starter #16
thats a good point. i really do not know because i did not build the engine myself. i bought it already assembled. and the guy that did build it is now in jail and even if he did screw it up there is no way to make him do the labor..... may be pullin an all nighter comin up. that idea was kinda sitting in the back of the head cause i really didnt want it to come to that... thank you
 

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If the battery is good pull codes and perform KOEO from the PCM and see what if anything kicks out.....

Is PCM, power control module, vehicle computer OK....

X2 on the cam and crank so maybe tear down time...PITA...

If you pull codes and or perform KOEO and get code; 67 A/C or NSS issue, take a few minutes and turn the key to RUN (engine off) and pull the column shifter down into the D position and secure it in place so it won't move, crawl under the truck and loosen the column shift linkage bolt on the transmission tab just enough to "click" the tab all the way back until it stops, then 2 clicks forward and tighten the bolt replace shifter in P....Referenced in the Haynes Manual as "Point A" in the illustration..

Many times we all have to jiggle the shifter, holding it upward to "start" the vehicle but the code 67 may indicaste it's the NSS when really all it takes is to "syncronize" the column shift linkage with the transmission going thru PRNDDL.....a bit of a stretch perhaps but simple to perform and eliminates the NSS all together as a "starting" issue.....

What was the out come with your "starter relay" ....test the (S) side for voltage thru the cable down to the starter motor, no voltage, no start...

Make sure ALL the wires and cables that converge there are hooked up correctly...clean all the ends of corrision for better contact and continuity AND ground the NEG battery cable to the frame as well. ...

How old is the TFI - thick film integrated module on the distributor, pull it and test for free...

Good Luck ~ :thumbup
 

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Discussion Starter #18
When i put the new harness in it fixed the starter relay prob along with some other grounded out wires. with the old harness we could not even hook up to the cpu and have not had a chance to try with the new harness. we will see...
 

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Discussion Starter #19
Update: did a compression test on the new motor and didnt even get past 5-8 cause the highest reading i got was about 60 ps1..... infact # 6 had 0.... never seen that before.....i never checked it before beacuse i was told that the heads were pressure tested when i bought the motor. when we did a leakdown every cylinder had either the intake or exhaust valve stuck open. I had another set of heads off my 86 engine, so i got them machined. i taked to the guy that i bought the motor from he said he had 2 engines out when throwin this one together..... my ? is pushrod lengths. i have an 89 engine..... are there any differences between the lengths in years?
 
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