Truck runs good till it warms up. I turn it off for a few minutes. When I start it, it seems like I am running on 2 or 4 cylinders. I rev it up some and it is good again. sometimes it has a single miss while running
When was the last time you had a tune up?
Might be getting coolant in a cylinder. Simple test, check the coolant level in the overflow bottle when the engine is cold, now warm the engine up. Did the coolant level rise? It should.
Simple test number 2 connect a fuel pressure gauge. Does the pressure stay steady when you turn the engine off? If not you’re probably getting fuel in a cylinder from a leaking injector
What is there to tune up on a newer ECU vehicle? this term is so misunderstood. back in the day a tune up was when you made adjustments to your carb and distributor and with changes you were actually adjusting the timing and air/fuel flow. then you would be tuning your engine to run at maximum proficiency.
today all your electronics do the work for you. what you are confusing as a tune up is diagnosing what could be wrong with a car’s engine.
i would start here…
https://www.aa1car.com/
and get your hands dirty.
cheers
Explained nicely right here…
On a 94 Ranger?
I can think of a few things.
Distributor cap, rotor, spark plug wires, spark plugs, and coil,
Tester
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a 94 ranger has a distributor cap?
https://www.rockauto.com/en/catalog/ford,1994,ranger,3.0l+v6,1137978,ignition,distributor+cap,7120
Tester
well teach me something about a 3L… all my trucks are 4L… is a 3l carbed also? if FI it will be computer controlled, so tuning and changing busted parts are still a different item. cheers
Mr @Tester pretty much nailed it… Don’t look elsewhere until the basics are covered in the tune up category. An engine miss is usually the one single item that actually prompts most tune ups in the real world where people are ignoring preventive maintenance schedules entirely.
Wires and plugs and cap n rotor, do not last forever…despite some thinking otherwise. Great place to start.
Sometimes you can catch bad wires by actually watching them arc thru their casing at night or in the dark when looking under the hood. I’ve seen this many a time as I’m sure others have as well. Pretty telling clue when you see it and you have an engine misfire.
Yep fire fly’s under the hood at night will tell a lot about the wire’s.
tossing money at parts that might not need replacing is a great way to go broke. the truck runs fine till warmed up and then restarted as OP says. if it is a parts problem won’t the engine fire badly all the time? If a carb was on this truck then YES you can actually manually give it a tune up. Just trying to clarify misinterpreted terminology.
A 25 year old Ranger qualifies for the classification of “newer”?
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newer than my 78 pinto 81 camaro and 302 swapped 83 ranger, these I have to tune as they are all carbed, so yes Fuel Injection and computer controlled are NEWER.
The terminology tune up may not be as accurate as it was in the old days, but there is such a thing as a tune up on most every vehicle old or new. Some "tune ups may only require spark plugs to be changed. With the symptoms of this particular vehicle a tune up would be the first thing to do if it hasn’t been done for awhile. It could save the user a lot of time and trouble if they do not have a lot of diagnostic experience or equipment. If it’s due for one and didn’t fix the problem, there’s no money wasted as it is due anyways. If it fixed the problem it’s a win win.
Early 90’s engine technology tended to be fuel injection w/distributor, coil, and electronic ignition module, and many used non-hydraulic lifters. Same as my Corolla. A normal yearly tune-up for that configuration includes
- replace spark plugs
- replace ignition rotor
- optionally replace plug wires and dist cap. per inspection
- check valve clearances and adjust if necessary
- replace engine air filter
- set warm idle rpm using air-bleed screw
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This is true, but whom was suggesting doing this? Also what does having a carburetor have to do with doing the absolute basics when it comes to having a known engine misfire? Do you believe that Spark Plugs, Cap, Rotor and wires are “throwing parts at a problem” to solve an engine miss? If so you would be quite mistaken.
I never suggest throwing parts at any problem and I have the skill set to find out exactly what was the culprit in almost any situation. For me to guide you to precisely what is causing your misfire via my computer desk would take an awfully long time and it would also assume you have the skills to handle the job in the first place.
The suggestions you were given are par for the course in engine misfire territory… Carb’d or Fuel injected, makes no difference. Injected is actually easier, but… I digress.
i am not trying to get into any pissing matches with anyone. what i am trying to do is educate to the proper terms of what people are talking about. replacement maintenance and diagnostics are 2 separate animals. hey if spending 50 bucks on new wires FIX the problem, great! problem solved, but if not… now what most people will do is change every 1 all at once, instead of 1 at a time then re-firing engine to see if that fixed anything… ahhh real diagnostics.
now change plugs, wires (cap if you have one) coil pack, and still have the problem. hmmmm bummer, now what… must be a sensor, etc. etc…
Fuel injected engines are run on air flow into the engine as all the pressure never changes. so this gets into a fuel/air prob.
here is what i was linking to earlier…
https://www.aa1car.com/library/misfire.htm
all of the diagnosis is laid out here to where to check and all the possible problems.
calling swapping new parts for old a TUNE UP is not tuning an engine as I stated above. think of it this way, tune a guitar by swapping strings?? no, you tune a guitar by turning the keys, makes a DIFFERENT tune, as will adjusting the air/fuel screws on a carb. you get a different tune from the engine.
cheers and hope this helps someone.
Okeedokee… Thank you for helping me out with that. Was trying to help you out with a very easy to diagnose and remedy issue. Sounds like you have it all sorted out and do not need my amateurish at best assistance.
Let us know how you make out…or not.
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