Hey guys. Back in January of 07, I bought my single cab XLT 96 Ford ranger with a 4.0 v6 from a used dealership an hour away, and it looked real nice. April of 07, I brought it and got a synthetic blend oil change from walmart (70$) it included some bonuses. May of 07, i had 2 dirtbikes and a passenger in it, and i was accelerating up a steep hill on the highway in 5th, and my truck started misfiring. My check engine light came on and was blinking. Being that we were running late on time to the race, we said fuck it and did the rest of the trip. It was misfiring like a mofo (lack of power, cant pull at 2500RPM from 3rd to 4th, couldnt be in 5th under 60MPH)

I went to autozone the next day (May) and got platinum 2's and new wires. While i was at autozone i got P0303 and P0305, 3 and 5 misfire. When taking the spark plugs out, i noticed that each of them had a different burn pattern on them. Some were tan, others were white, and others were black/wet. After replacing the plugs and wires, the check engine light was still on, but the vehicle was running fine. I said fuck it, and drove it how it was.
In July, the check engine light started blinking alll the time when i was accelerating, and i noticed that the misfire started to come back. Frantic, i took my truck back to autozone, and got P0174 and P0300. Engine bank # 2 too lean, and random misfire. The guys at autozone didn't know what to say.

I took it to the local stealership, and they gave me a new cat, along with new wires, did a leakdown test, a compression test, checked my coilpacks, and a fuel injection flush. Cylinder # 4 had 8-10% less compression than the other cylinders. No problems when they did the leakdown test. The cat didn't fix the problem, and neither did everything else!

Then, they told me that i was to get the stock autolite plugs. That's probably why she's misfiring. So, i went back to autozone, did a scan again, and got back p0174 and p0305. Picked up autolite plugs, installed them, and it still runs like garbage. by the way the platinums looked brown.

They told me to forget about fixing it and drive it til it dies. I got a refund the last time i went because they told me they'd find the problem and didn't. I've been there 4 times since july.

If i were to let them take it in for a few days and do a FULL diagnostics, they have no idea how long it would take to pinpoint and they would probably just be throwing parts at it until it was fixed. The labor would be very expensive.

I want to get rid of this friggin thing ASAP i shouldn't have gotten it. this thing has been trouble for me since the day i bought it.

I'm willing to accept any ideas of why this truck isn't running well. DIY is preferred cuz im poor. F.O.R.D!!!!

I have a fuel filter waiting to be installed for this truck. It is also to be noted that I was using an STP fuel additive for use after an oil change. i mixed it with a fuel injection cleaner in 16 gallons (1 bottle of each) on the way to the race.

I want to trade this truck in for a car that i can DD cuz by the beginning of spring I'll have my TOYOTA up and running.

This ford is getting 10MPG. The exhaust smells like gas. Clearly, the 'too lean' code is making the engine consume more gas, and the misfire is causing excess gas to be exhausted, uncombusted.

I think it's not an ignition problem, because my coils were in compliance and my plugs and wires have been changed over more than once.

http://a763.ac-images.myspacecdn.com/images01/29/l_62e4cf3e0c700fe66ee0585f3ade1dba.jpg

check the fuel pressure at the rail and the reading for all the o2 sensors...disconnect the sensors one by one and if theres no change from one, you found the culprit...cant remember the fuel pressure, but i think its 45 PSI at idle is the spec..

I would suggest replacing your O2 sensors since you got a bank 2 lean code. Chances are they're all nearing the end of their life, so I'd do all of them (3: one for each bank, than one after the cat, IIRC).

Another possibility could be the ignition (EDIS) module. You said they tested the coil packs, but take that with a grain of salt. One of the coil packs in my wife's Firebrid tested OK but it's cylinders had a misfire code. One night, in frustration, she wound the piss out of it and hit the rev limiter--bam! Check engine light came on. That last strain finally made the coil test bad. Once the new coil was on, ran great with no problems.

how much is that going to cost? im poor

Call aroun to some local parts stores and find out. I'd recommend new O2 sensors, but cheap used ignition parts you can try for troubleshooting purposes, but you never know what you get. Look out for people parts other 4.0s, and ask a Ford dealer what years/models parts interchange.

I would swap out the O2 sensor....

this truck doesn't have the original engine in it. the original engine was 1FTCR11X4TPB29097 but the engine in it now is 1fmdu34x2tuc21073

The "X" in in the VIN means 4.0 OHV for both.

things are so much easier under my toyotas hood with a 2.4L i4.

thanks for the responses guys. Its been below freezing for the last few days, and this afternoon when i pulled out of my parking spot, late to work, i saw a couple puddle marks. they were in the general area of under my gas tank.

We had some of these trucks at my old shop and we used to replace the fuel pumps at least once a year so x2 on fuel pressure. Also I would run autolight plugs they seemed to work the best in fords and you might check the iac valve. These are things that would regularly go bad in my experience. Or find a cliff put in neutral and give it a little nudge.

i like the cliff idea. it's crossed my mind more than once. i'll check that valve and my fuel pressure. i just want to get the CEL to turn off so i can sell it.

The idle is rough and the engine shakes. it misfires worse when im cruising as opposed to flooring it. 5th gear misses every second. some days i can drive it and i'll feel it shudder every once in a while, but the check engine light will stay on. Other days, the check engine light constantly blinks and the truck bucks everywhere.
it has the most problem going up hills, and coasts down hills without a misfire.

when the air conditioning or heater is on, the idle is rough even more so; engine shakes, exhaust wobbles

hey erick..
I have a 99 ford explorer with the same problem.. I have the 4.o also but with an automatic


first let me say i have changed the coil packs 3 times and no diferance
I have tried all the avail sparkplugs out there..
took it to a shop and they told me that the valves were carboned bad.. but when i went to have it smogged it passed the emissions .. like a brand new motor.. the check engine light didnt come on thank god.. while the test was being done
called alot of people and they said it might be the computer .. now the coolent sending sensor is being burned up and throwing the code for it not working..
I have checked the wires to the engine,, all good ..tried to get another harness from the brain to the engine but no luck the stealership stoped making them a few years ago..
so now we were going to replace the computer for 150.00 from autozone.. and try that.. if this helps I am glad..
I hope there is going to be a recall on this problem..lol

laters mike

thanks mike for the unfortunate news about your FORD lol

when are you gettin that part? any time soon? I'm going to go along with everything that people have said so far, and if that doesn't help, i'll go ahead with your plan.

With it running at idle spray non-chlorinated brake cleaner around the intake manifold. I have seem intake manifold leaks and once a bad injector O ring. The brake cleaner will change the idle if it is sucked in through a vacuum leak.

While you have the brake clean out, use it to clean the MAF sensor in the intake boot. Let us know what happens.

it doesn't change the idle. i have no vacuum leaks.

I just bought new autolite plugs, coil pack, wires, did an oil change and oil filter change, and changed the air filter.

I sprayed the MAF with brake cleaner.

No improvements in the way it runs.

The idle is high when i come to stop lights/stop signs, and it takes about 2 seconds for it to drop down from 1500 to 900rpm with the clutch and brake in.

oh another update on the quality of my ford lol


its sipping about 1 pint of coolant every 200 miles, but the engine shows no signs of a coolant leak. the oil was black, the plugs brown, and the exhaust smells like gas - oh when i start it up (it's been below 40 for a couple weeks) theres white smoke out of the tailpipe, but thats common right?

if its leaking coolent but you dont see it you may have a bad head gasket or intake manifold gasket, althought if the dealer checked for compression the head gasket should have been found. i would suggest a BG fuel system clean done to this truck. this is a very efective cleaning process that will compleatly clean out all fuel system components, i recomemd changing the fuel filter with this also.
give that a try many people are shocked of how good of job this will do. if there is any problems with your fuel syatem (becides the pump or a completly dead injector) you should notice pretty good results

guys can you help? i noticed something weird that i thought i should mention about the order in which my wires are plugged into the coil pack.

Firewall
(3) (6)

(2) (5) <-engine

(1) (4)
Radiator


I know that the firing order is 1-4-2-5-3-6

Firewall
(3) (4)

(2) (6) <- Coil Pack

(1) (5)
Oil Fill

I don't know the order in which the wires should be plugged into the coil pack, but the wires have been plugged into the coil pack in the order of the picture i made. I don't think it's wrong though, because of this picture
http://www.therangerstation.com/tech_library/diagrams/FiringOrder6a.gif

http://i219.photobucket.com/albums/cc64/NetraToy/38d75c6c.jpg
http://i219.photobucket.com/albums/cc64/NetraToy/8c065919.jpg
http://i219.photobucket.com/albums/cc64/NetraToy/8017fe94.jpg

oh another update on the quality of my ford lol


its sipping about 1 pint of coolant every 200 miles, but the engine shows no signs of a coolant leak. the oil was black, the plugs brown, and the exhaust smells like gas - oh when i start it up (it's been below 40 for a couple weeks) theres white smoke out of the tailpipe, but thats common right?

Some vapor is normal at start up. H2O is a normal by product of combustion.

The flashing light is a severe misfire detected by the computer. If you are using coolant and have a misfire, you have a cracked cylinder head. OHV 4.0L Fords are notorious for having poor cylinder heads. If you have a emissions station that is availible in your area, they can stick the exhaust probe in the coolant over flow tank and test for HCs (hydrocarbons=unburned fuel). This will tell you for sure that the head is cracked and the coolant is causing the misfire.

I've replaced 3 4.0L heads in the past year due to this at my shop.

wouldn't the tests that the stealership did show i had a cracked head?

Lol just got off the phone with the used car/truck place i bought this from...and i told them that both the carfax of the current VIN of my truck and the VIN of the engine that they put in does not match their story. They sounded nervous. I want the truth!

A leak down test may or may not show a cracked cylinder head. A HC test will show for sure. When the engine is warm, the metal expands and may present more of a leak than when it's cold.

The lean code in bank 2 is due to the misfire, not O2 sensor failure. If the engine is misfiring, more air is introduced into the exhaust, thus making the computer think it's running lean. An oxygen sensor can only monitor air, not fuel.

Makes sense. I had a compression test done as well. Would that show that i had a cracked head with a semi-cold engine? The compression test showed 8-10% less compression in cylinder # 4. My CEL is blinking a po305 (5th misfiring) :-S

Can the IAC and MAF both being faulty at the same time cause a misfire ? I've cleaned both those parts but theyre not new.


Lets say i have a cracked head. how many hours of labor is that and what has to be replaced as well? grand total ~$ ??

it keeps running worse and worse every day. i cant even put it in 5th under 70MPH now or else i'll constantly stumble and even with the pedal floored, i lose speed on a flat.

i'm going to do a coolant flush. Is it wise to put stop leak in the radiator system? If i've got a leak thats making me misfire, could this help hide the problem, at least? I wanna get rid of this thing. I paid 3500 for it and i've put over 1500 in it trying to fix it.

i changed the fuel filter, and unplugged the battery to clear the CEL. It ran fine for about 2 miles and then ran like shit for 3 until the CEL came back on. It still runs the same way.

I put 200 miles on my truck again since the last fillup and coolant check, and my coolant is still topped off (checked it after 1 hour of it sitting after driving it for 10 mins from work to home)
I wonder why all the misfiring in the last 200 miles i've been experiencing has not burned any significant amount of coolant? There are no signs of an oil or coolant leak.

I've been doing A LOT of reading, and it seems that almost every problem that causes p0174 to show up also causes P0171. MAF, intake manifold, PCV, etc.

Bank 2 is cyl 4-6, which would make sense why p0305 is present.

Is it my 5th cylinders injector? I'm going to check the PCV tomorrow, and replace if needed.


how can i make this stop misfiring so i can get rid of it before it blows up?

OMFG
http://i219.photobucket.com/albums/cc64/NetraToy/DSCF0887.jpg
torn apart
http://i219.photobucket.com/albums/cc64/NetraToy/DSCF0883.jpg
4th injector
http://i219.photobucket.com/albums/cc64/NetraToy/DSCF0884.jpg
The 5th injector's plug was on...backwards!!! stupid stealership.
http://i219.photobucket.com/albums/cc64/NetraToy/DSCF0875.jpg
and the plenum was completely covered in carbon.
http://i219.photobucket.com/albums/cc64/NetraToy/DSCF0885.jpg
so i cleaned it out, PUT THE PLUG ON CORRECTLY, buttoned it up, and...the idle is racing after pressing the gas.
http://i219.photobucket.com/albums/cc64/NetraToy/DSCF0903.jpg
I've checked all my vacuums and the idle doesnt go higher when i spray brake cleaner around the engine. i didn't change any adjustments with the throttle.
I bought a new IAC and it didn't help the idle. My only code is p0171.

when i start it, the idle goes to 2,000RPM, and stays there for 5 seconds, and then quickly drops to 1,000RPM. When i press the gas to any RPM, the engine stays at that RPM for longer than i hold it there, sometimes as long as 5 seconds at the same max RPM that it is brought to. When i come to a stop, the engine keeps trying to rev even when im braking and not gassing it, and when i sink the clutch, it sits at 2,000 RPM for 5-10 seconds.

hELP

at least it's not misfiring anymore. but theres always a new problem huh

Can the IAC and MAF both being faulty at the same time cause a misfire ? I've cleaned both those parts but theyre not new.



From my experince you can not clean the IAC, I've tryed it before and it didn't fix my problem, when a new one or one I knew to be working did.