99ranger misfire #4 need help

[fat freddy]

my truck misses code says #4misfire changed coilpack put autolite plugwires on and plugs changed injector #4 put new camshift & crankshift position sensor put bosch oxygen sensor on . each time i changed a part i would take the - cable off and clear the code. but the code comes back misfire #4.
I have had a p1131 come up twice in two months and a po133 once.
neither one has been back on in a month but my misfire #4 is still thier
and my truck still misses.can someone please help me



fat freddy
99 ranger xlt 4x4
3.0 flex fuel

 

[icepounder]

Did you have the codes cleared with a scanner ? If you did and they came back I would check the grounds first. I had a similar problem and it ended up a bad ground on the drivers side fender by the fuse block.

 

[ExplorerDMB]

P0133 O2 Sensor Circuit Slow Response (Bank 1 Sensor 1)

did you replace the right sensor? That is the on the passenger side before cat.

P1131 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 1

the P0133 is OBDII while the P1131 is Manufacturer specific.

Hope that helps

-Drew

 

[fat freddy]

changed 02 sensor on bank 1 took neg terminal cleared code checked ground wire next to fuse box . drove truck check eng light came on misfire #4 truck still misses
took out plugs #1.2.3.4. had soot on them #5.6 look pretty good
will motercraft plugs & wires help my problem with the misfire and the soot?
or is the autolite double platinum app103 fine? 99 ranger 3.0 4x4
fat freddy

 

[ExplorerDMB]

I know you said you changed bank one sensor, but theres two sensors for bank one - before cat and after. Which one did you change?

-Drew

 

[fat freddy]

the one before cat the other one is between the two cats in a single pipe.

 

[fat freddy]

my truck has 3 02 sensor 1 driver side 1 passenger side and one between
the two cats changed driver & passenger side 02 sensor misfire #4 driveing me
crazy need help

fat freddy
99 ranger 4x4 3.0 flex fuel

 

[ExplorerDMB]

So the code your getting is P0304, correct? If you have changed the plugs, wires, and injector; then something isn't right. Make sure your fuel injectors are pulsing, make sure you have spark on that cylinder. If you have both of those, than you need to do a compression check on the cylinder (might as well do all).

-Drew

 

[fat freddy]

done a compression check #1 is 160 psi lowest is #6 145 all the ones are
between 160 &145 #4 is 148 psi what would make plugs have soot on them

fatfreddy 99 ranger
4x4 3.0 flex fuel

 

[fat freddy]

how do you check to see if the injector are pulsing

 

[ExplorerDMB]

It is a tool called a "noid light"

basically plugs into your injector connector and "flashes" to tell you its pulsing

read here about spark plugs: http://www.dansmc.com/sparkplugs1.htm

If , black and sooty the engine is running too rich in the fuel departement or too cold of spark plug.

Hope that helps

-Drew

EDIT: heat range is vital for these engines now aday. Trying buying a new spark plug (or a known good one) and putting it in to see if it changes.

 

[fat freddy]

what could make it run to rich ? should i get motorcraft plugs & wires
thanks for your help i will try a noid light .get back with you later
to let you know what i find

 

[ExplorerDMB]

a bad injector will possibly cause it to run rich while the injector may be getting stuck open or something similar. Motorcraft plugs atleast.

-Drew

 

[fat freddy]

took truck to garage they said it could be a blowen intake manifold gasket.
or posible valve guide problem or a burnt valve
any and all comments welcome thanks

fat freddy
99 ranger 3.0
4x4 flex fuel

 

[ExplorerDMB]

If it was a valve guide/burnt valve it would have low compression - which you said it didn't. The intake manifold may be an issue. I know some people have issues with them on their 4.0s, but it usually causes a false O2 sensors reading.

-Drew

 

[fat freddy]

are the valve guides hard to change ?
would the intake manifold make a misfire on #4

 

[ExplorerDMB]

depending where the intake is leaking - it's possible. The seats should be done by a machine shop. You'll want to also get the heads straightend/machined and let them do all the stuff they do. It shouldn't be too expensive for them to do it.

-Drew

 

[fat freddy]

could my pcm be causeing the misfire #4 and
making it miss? if so
how could i check it?
fat freddy
99 ranger 4x4
3.0 flex fuel

 

[ExplorerDMB]

I highly doubt that your PCM will be causing you a misfire on #4. When a computer issue happens, it usually causes a lot of different problems. I think your problem is mechicanl!

-Drew

 

[fat freddy]

I put a intake manifold gasket on my truck no change still misses
I noticed in the air intake the #1 2 3 5 6 ports had a lot of buildup.
But the #4 was noticeably cleaner. even in the manifold I could see
the intake valve it was pretty clean too any comments .


fat freddy
99 ranger 4x4
3.0 flex fuel