Late 1986 ford 302, half ton pickup

Color of spark is a kinda age-old test, but it doesnt necessarily mean anything. Some cars you will usually see orange during a cranking spark test because the resistance of the system and the coil windings reduces voltage below the "blue" spark level until voltage gets over 14v, which doesnt happen until the engine is running.

If the car runs at idle and rev, it is unlikely its the pickup coil. The pickup is the RPM sensor, pretty much it either works OK or works terribly/not at all (though sometimes they are funny, its rare). If it runs fine for awhile, then after 30 minutes it starts to cut out or stall, and when it cools it runs again, THAT is pickup coil type of failure, but not yellow spark. Pickup doesnt make spark or affect its quality in any way. It simply says WHEN to make spark. After it signals WHEN, the module and coil and source voltage determine how much is made.

If you still think you have low spark issues, id test it with a test plug. Its an adjustable or fixed gap spark plug you can buy at a parts house. You need minimum 25kv consistent spark from the coil.(30 is better). What that means is you hook a work from the cap to the spark tester, and with the engine running it will fire regular sparks and not skip any. If it does...spark is not your problem. Period. If it doesnt, then you start checking wires, resistance, voltage, etc.

For this types of problem,there are few help inks to troubleshoot the problem.Click the link below to go through the troubleshooting procedure to resolve the issues :----Idles rough and quits when gas pedal is pressed less? http://technoanswers.blogspot.in/2012/01/1999-ford-f-150-idles-rough-and-quits.html-----------van idles rough? http://howtobyme.blogspot.in/2012/01/2004-ford-freestar-van-idles-rough.html
--------------runs lean and idles rough? http://technoanswers.blogspot.in/2012/02/ford-runs-lean-and-idles-rough.html
-----------Car still runs Rough after tune up? http://howtobyme.blogspot.com/2011/12/car-still-runs-rough-after-tune-up.html
------------Idle flair is noticed on car? Rough idle? car will not idle? Erratic idle speed? http://technoanswers.blogspot.in/2012/02/idle-flair-is-noticed-on-car-rough-idle.html
----------High rpm in neutral? Inconsistant high RPM in neutral? http://technoanswers.blogspot.in/2012/02/high-rpm-in-neutral-inconsistant-high.html
------------Engine Backfires? http://technoanswers.blogspot.in/2012/02/jeep-backfires.html----------- Nissan stalls and bucks on Acceleration?

http://technoanswers.blogspot.in/2012/02/nissan-pathfinder-stalls-and-bucks-on.html

-----------
Nissan Pathfinder Backfires? http://technoanswers.blogspot.in/2012/02/nissan-pathfinder-backfires.html
---------How to adjust rpm? http://schematicsdiagram.blogspot.com/2011/12/how-to-adjust-rpm-on-2009-dodge-charger.html
------------Engine cuts out at 3000 RPM? http://schematicsdiagram.blogspot.com/2011/12/engine-cuts-out-at-3000-rpm.html
----------This will help.Thanks.

that is odd,thinking possibly a burnt valve tho,check compression yet?

Check engine light? Have you checked fuel pressure?

Hi,
Please 1-check the PVC Valve. Block off the PCV valve and see if the miss goes away. If it does; replace it.
2-The other thing is to check the plugs to be SURE 100% SURE - they are factory rated for that engine. 3-check the fuel filter.
4-Remove the negative battery cable and give the on board computer 20 minutes - then re-connect and run the motor 20 minutes for the engine to adjust to the new settings.
5-Lastly if nothing else works -I will simply suggest a compression test - sounds like a valve may not have seated perfectly or is burnt.

check for a vacumn leak, my buddy has a 96 dually that did that,found out it was his temp sensor to the computor,was showing a negative # when i tested it,he replaced it and it fixed everything! He couldn't believe it LOL

library should have one sometimes they have the older versions of manuals on there bookshelves, auto parts store

I’m happy to help further over the phone at https://www.6ya.com/expert/gregory_8e6ba270263743ac

look about half way up the drivers side of the transmission there will be a large 'bolt' head its a fill plug loosen it, its only about a half inch long take it out and if fluid runs out or you can take a finger and touch fluid inside the transmission you are good

I'm not too familiar with an 86 302. Does it have essentially the throttle body unit to meter the gas? (looks like a computer controlled 2 bbl carb) or does it have some some funky intake system?

At any rate, check the tightness of the bolts where the throttle body unit attaches to the intake manifold. You may have to replace the gasket (if any) that resides betwixt these two pieces as well. Sound like a vacuum leak, so check the boss on the "back" of the motor where many vacuum lines are connected and make sure they are all firmly on their nipple and check the condition of the vacuum lines themselves to make sure they are not cracked or split.

good luck.

sounds almost like the newer vehicles equiped with cam sensors instead of the distributer system i had a similar problem with an 87 ford bronco 2 it would stall out right around 2800 rpm i replaced the control module usually mounted on the distributer at least mine was and it fixed it right up but as for ur truck im not sure they are only like 30 bucks at autozone or something worth a try right??