my 1999 ford ranger, when started, shakes and then while i am driving. my check engine light is on and reads a #3 cylinder misfire. i have taken it somewhere to get it checked out and they can't figure out what is wrong with it. this problem only happens 50% of the time. i don't know what to do, and was just wandering if anyone else has had this problem and new what it was or if anyone could help me figure out what is wrong. Also just got a tune up.

thanks in advance. it is much apreciated.

 

Far from an expert but could be a bad/ intermittent plug or plug wire. Reasonably cheap to check with new ones.

 

First off I would check to see that each plug wire is tightly seated on the plug, especially the wire to cyl. # 3.

 

Ma truck dunt wok, whadda eye du

you need to tell us exactly what the shop did........details!!!!.........what engine do you have....details details details

 

Gunnerboy,

Welcome to FTE!

As Power stated, to get the best advice we can give, share all the details you can think of. You may want to characterize what you feel is most important, or in this case, also what the garage mechanic said. But don't forget the seemingly trivial details. These sometimes are as or more important!

As our fellow colleagues suggest, it could be as simple as a bad wire or plug. The thing to do here is rule out the obvious before a deeper dive is warranted. When dealing with the ignition system, take precautions and care when doing checks with the engine running. As Michigan notes, check how the boots/wires are seated on the plugs, but do it with the engine off. Look for arcing along the wire, especially in the area of the plugs.

I used to have an MSD ignition system on an Escort GT I had. I could tell when I had baked a wire through (happened frequently) when the car would miss. That was an indicator that I needed new wires. I'd change them and the symptom would go away. It used to eat plugs too (hot ignition system from the increased current/voltage).

Let us know the details!

Kevin

 

i have a 4.0l v6 1999 ford ranger xlt. when i turn it on (mostly in the morning or the first time i turn it on that day) it shkes violently. sometimes if i rev the engine up to 3000 rpms it goes away but usually not, also restarting the car or just letting it idle makes it go away to sometimes. it is kind of a violent shake and makes me feel like i'm drivning down a really ****ty road, but i've driven down those road before and have been ok. when it is idleing it shakes when i accelerate it jerks back and forth almost like i'm constant tapping the accelerator but not as bad because it is not to constant just every 10mph.

While at the mechanics the didn't experience it actiong up. mechanics said wires, plugs coils- new, vheicle starts hard rides fine. did not find a misfire problem. felt drivelind vibration and balanced tires (still shaking though).
sorry about the limited info but if you need anymore information just ask

 

one big problem that i have with our 99 ranger ( 4.0 ) is it will shake like what you are saying and so far it has turned out to be the plastic cooling fan that has lost some bldes that throw it out of balance , been replaced 2 times in last 3 years ! have you ever changed the fuel filter , checked fuel pressure ?

 

While at the gararge it didn't act up, so they suggested throwing new plugs, wires & a coilpack at the problem, so I'm not clear on IF the wires, plugs & coilpack were replaced or not & IF the miss is still present?????
Now you say it starts hard, does this mean you have to crank the engine longer before it'll fire & run?????

A number of things can cause a miss like this, like plugs or wires, but a sticking valve, acting out fuel injector & maybe sticking piston rings too, so you need to do some more diagnostic work & you won't need a bunch of special tools to do it, if you can fill us in more clearly on what was or was not replaced by the gararge.

Operating the vehicle with this misfire isn't doing anything any good, especially the cat converter, so you need to concentrate on finding & fixing the missfire. If your revving the engine high while sitting still, the computer rev limiter will cause it to run rough if it's bumped, so don't rev it high without a load on the engine, thats not good for it.

Post All of the trouble code Numbers you have.

The driveline vibration problem can wait.

 

they said the look new( i'm planning on replacing the wires plugs, and coilpack and fuel filter). so nothing was replaced by the garage... they only did diagnostic. by starting hard they mean it shakes when started but not while driving. today it acted up really bad and felt like it was puttering a lot like losing power or going empty on fuel especially when i accelerated. and the only code they said they came up with was the p303something or another which was the #3 cylinder misfire.

 

OK, they didn't replace anything, so don't you begin to throw parts at it either. Do a proper trouble shoot, find the culprit, Then replace the faulty part.

Maybe consider beginning by raising the hood after dark, start the engine & look for arcs & sparks along the #3 plug, wire from the coilpack to the spark plug.

Edit: I doubt that you have a coilpack problem, as the coilpack fires the plugs in pairs & you don't have a trouble code for the #3 plugs coilpack companion, the #4 plug.

If you don't see anything, try wetting the #3 plug wire down with a spray bottle of water & see if anything turns up.

If no joy, pull the #3 plug & look for internal ceramic insulator damage, like hairline cracks, electrical break down carbon tracks, chips, carbon fouling, ect.

If no joy, rig a stethoscope using a piece of rubber tubing, long screwdriver, broom handle, ect, to listen to the #3 fuel injector, to determine if it's "click" sounds different than the other injectors.

If no joy, listen around the #3 cyl valves, to determine if you can hear if one may be sticking & is more noisy than the others.

Let us know what your preliminary trouble shoot turns up.

 

recently i was driving down the road in my 94 ranger 3.0liter 2 wd and the truck started to shake so i pulled over and checked my drive shaft nothing.. so i got back in and it did it again but this time the rear wheels locked up.. anyone know what this might be? its not the rear end because i took the cover off and the gears are fine.

 

I had this exact same problem. I left it alone, but it got to where 3 of the cylinders were misfiring in one trip around town. I replaced all of the spark plugs and wires, since I had recently gotten the truck from someone else and didn't know how old the wires were, and that fixed the problem to where it only happened about once a month.
Then it got worse. Cylinders started misfiring again and some days my truck just wouldn't start at all. In the end, we had to tow the truck home and replace the fuel filter and pump. I haven't had a misfire since then, and that was about 4-6 months ago.
Start with the spark plug wires, then if it persists, replace the fuel pump (be sure to test the current first, though, because fuel pumps are expensive).

Also, not sure what you mean by "mechanics said wires, plugs - new…", but if you already have new plugs and wires check the fuel system.

 

Welcome!!!

My first thought is plug wires too. Just adding it to the mix. If they are of an unknown age then its not a lost project to do them and the plugs!

 

I have 1999 ford range 3.0 it misses at idle ant shutters at 45mph i replaced wires, plugs, fuel filter, camshaft syncronizer, but still does the same thing but never had a check engine light, and replace MAF sensor last month. What do i do.

 

FUEL PUMP CAN BE 1 PROBLEM !
CHECK THE FUEL PRESSURE !
WHAT TRANNY DO YOU HAVE ?