AMC Eagle Den Forum

The Mighty 258 => The Engine => Topic started by: el-camino on October 23, 2011, 01:54:57 PM

Title: fuel in exhaust and only 5 cylinders
Post by: el-camino on October 23, 2011, 01:54:57 PM
hi all
today i have a special question, it´s not my Eagle. i bought a 1994 Grand Cherokee 4.0.
@Admins
if it´s not ok, you can delete my question

last week i bought a 1994 Grand Cherokee 4.0.
the old owner says: only the alternator and one spark plug wire is dead.
ok, today i change the alternator and the spark plugs, rotor distributor cap and spark plug wires.
i start the engine and the volt-meter says only 12V
i open the fuse box and the 2 fuses with 60A was blown.
so i change the fuses and start again, ok, the alternator is now working.
But the engine runs only on 5 cylinders and smokes like heck and the fuel is dripping out of the exhaust.

a friend of mine says: hole in piston
i don´t think so.

i pull of the spark plug wire from the 5th cylinder is no change and i dont have seen any spark springing around :'(
when i accelerate over 2000 rpm i think all 6 cylinders works.

and one time, the engine runs in idle, the engine shut off.
i will start again, no reaction.
i can not hear the fuel pump.
so i disconnect the batterie, wait a little, connect the batterie again, switch on ignition an the fuel pump works again and the engine starts.

can it be the crankshaft position senson or a another sensor ?
or the engine dead ?

i think here in the Eagle Forums finds a lot of members with this engine
thanks

thanks for all ideas
Title: Re: fuel in exhaust and only 5 cylinders
Post by: rollguy on October 23, 2011, 04:10:53 PM
I would say to do a compression check.  If one of the cyls is low,  next would be a leak down (cylinder differential pressure) test.  The leak down test will show where the problem is.   If air is heard in the intake, an intake valve is bad.  If in the exhaust, then an exhaust valve is bad.  If air is heard in the crankcase (through oil fill), then you have either bad rings or a hole in a piston (as others have suggested).
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on October 23, 2011, 04:43:59 PM
hmm, a lot of things to check.
only one idea: it is possible that injector nr5 are permanently open and this is the reason for the overflow ?
Title: Re: fuel in exhaust and only 5 cylinders
Post by: Jurjen on October 23, 2011, 05:06:34 PM
Injector could be faulty, swap it with another cylinder and check if the problem moves.
And a compression test of course...
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on October 24, 2011, 08:02:21 AM
compression test is done, full power on all 6 friends ;D
i read in the book, the camshaft position sensor, located in the distributor.
if its posible that thing will not work correct ?

blinking trouble codes
12
55

nothing what have to do with my problem :lurk:
Title: Re: fuel in exhaust and only 5 cylinders
Post by: carnuck on October 24, 2011, 10:20:36 AM
Bad injector is flooding the plug and snuffing the spark.
Title: Re: fuel in exhaust and only 5 cylinders
Post by: BenM on October 24, 2011, 11:16:23 AM
Check all the fuses, especially the little tiny ones under the hood. They power all kinds of sensors. Follow the wiring harness around and look for breaks and wear.

Though maybe not the problem, I would worry that part of the injector harness is shorting out.
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on October 24, 2011, 12:47:21 PM
thanks all for the help
tomorrow, when i find time, i will check the fuses and harness.
after this, when nothing is to see, i pull out all injectors with the rail >:(
The story continues....
Title: Re: fuel in exhaust and only 5 cylinders
Post by: HappyPappy on October 25, 2011, 07:32:13 PM
You can also try dumping a WHOLE can of Sea Foam in the gas tank, see if that loosens up the stuck injector, if that's the problem, also add some to the oil, it works wonders in there
Title: Re: fuel in exhaust and only 5 cylinders
Post by: ammachine390 on October 25, 2011, 08:00:38 PM
I think you have an electrical problem. You said you are not getting any spark to that cylinder. Are your spark plug wires in good condition. As casper suggested, check the trigger wheel inside the distributor.
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on October 26, 2011, 03:25:44 PM
today i had no so much time.
i check all fuses, all ok.
spark plug test on all 6 ok. sparks very good, also on 5
when i pull of the electrical connector from injector 1-4 the engine goes down with rpm´s also on cyl 6, but no changes on cyl. 5.
electrical or mechanical fail ?

today comes a guy and says: aaah white smoke, your head gasket are blown, miss the engine water ?
i say no, the water is ok and the compression is also ok on all 6
the guy says: aah, then must you have water in the oil...
i say, no..no water in oil, the oil have on a fuel smell
the guy says: aah you have a fuel problem
i say: i know :banghead:
Title: Re: fuel in exhaust and only 5 cylinders
Post by: 68AMXGOPAC on October 26, 2011, 03:43:39 PM
Too funny - good luck.
Title: Re: fuel in exhaust and only 5 cylinders
Post by: ammachine390 on October 26, 2011, 05:45:20 PM
Quote from: el-camino on October 26, 2011, 03:25:44 PM
spark plug test on all 6 ok. sparks very good, also on 5
when i pull of the electrical connector from injector 1-4 the engine goes down with rpm´s also on cyl 6, but no changes on cyl.

Sounds like the injector is stuck open then. Have you checked the number 5 spark plug tip, it would probably be full of carbon from running extremely rich.
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on October 30, 2011, 04:59:10 PM
thanks casper,
today i find time to do the electrical tests on the injectors.
14,4 Ohm on all 6, thats great.
the next test was 12v on the injectors, the click test.
all 6 injectors clickin fine ;)
tomorrow i will check the rest..... ???
Title: Re: fuel in exhaust and only 5 cylinders
Post by: Hawk258 on October 31, 2011, 03:10:11 AM
Odd question here, But have you tried to just pull the injector and put it in a bucket and start the engine? You should be able to tell if it is open full time or not.
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on October 31, 2011, 09:29:33 AM
ok, i don´t know why, but now comes the code :hello2:
code number 27
Injector 3, and/or 4, and/or 5, and/or 6 output driver does not respond properly to the control signal.

whats going on ? ???
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on November 01, 2011, 09:59:18 AM
just now i´m ready with the blink-test on the injector connectors.
Cylinder 1 -4 are blinking
not so cylinder 5 + 6
the test light is on but not flashing.
i checks the wires from the PCM to the injector connectors, the wires are ok.
and now ? bad PCM ?
Title: Re: fuel in exhaust and only 5 cylinders
Post by: Hawk258 on November 01, 2011, 01:06:49 PM
ugh, sounds very suspect.
Title: Re: fuel in exhaust and only 5 cylinders
Post by: ammachine390 on November 01, 2011, 01:33:07 PM
Did you make sure that the injectors are receiving 12 volts when the key is on/running? The PCM should only ground the injectors, so make sure that the injectors have power before replacing the PCM.
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on November 01, 2011, 01:51:32 PM
thanks all.
i will check this tomorrow morning, but i think the injectors have 12V with ignition on.
but i check it again.
i´m a little confused.
when this 2 injectors become not a impulse (Ground) they are closed.
the fuel in the exhaust makes me crazy.
tomorrow morning i remove the fuel rail with the 6 injectors to inspect this crazy things.
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on November 02, 2011, 12:20:39 PM
the last test is done. ;)
i pull out the injectors with the fuel-rail and go to ignition.
from injector 5 + 6 comes full power fuel, the other 4 are ok.
the next step, i pull of the electrical connectors from injector 5 and 6 and go to ignition.
now are all 6 injectors ok.
fail signal from PCM ? ???
Title: Re: fuel in exhaust and only 5 cylinders
Post by: Jurjen on November 02, 2011, 01:26:09 PM
That is a smart test.
Looks like a motor management failure.
Can you swap connectors or swap injectors to find out where the fault is?
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on November 02, 2011, 05:29:28 PM
Jurjen
yesterday i have tested the connectors from the injectors
Cylinder 1 -4 are blinking
not so cylinder 5 + 6
the test light is on but not flashing: no ground signal
i check also the wires from the PCM to the injector connectors, the wires are ok.

tomorrow i swap the connectors to have 100% points ;)
Title: Re: fuel in exhaust and only 5 cylinders
Post by: el-camino on November 13, 2011, 12:38:44 PM
today i plug the "new" PCM, YES :blob1:
the engine runs smooth and sounds good.
only one new code: 31
EVAP canister purge solenoid i think , i check it tommorow
thanks all for the help ;D
Title: Re: fuel in exhaust and only 5 cylinders
Post by: Jurjen on November 13, 2011, 12:56:27 PM
good news!
Title: Re: fuel in exhaust and only 5 cylinders
Post by: BenM on November 14, 2011, 12:54:06 PM
Good to hear. It's nice to get to the root of the problem without having replaced things that aren't broken.