Engine miss fire on # 4 , HELP !! (1 Viewer)

[Mo Rocks]

I am looking at buying a stock 1994 FZJ80 with 165,000 miles. $4K
No rust, very straight body, paint is good...faded hood. Clean underneath.
Has working factory lockers. Leather on front (manual) seats has worn like most. Rear windows will not stay up...they drop down about 3 inches. Regulators ??

The BIG issue is that the #4 cyl. seems to not be firing well.
Engine skips and does not have power until about 3000 rpm, then it seems to smooth out a bit...but can still feel the miss/skip/.
The #4 plug is black with soot....not oil. The other plugs looked normal.

Dry Compression:
175
175
185
165
180
190

So the BAD plug was on the # 4 cyl with the lowest(165) reading. I did the compression test with a new $50 gauge from Advance. I did it with all plugs out. BTW the "dealer" had someone put new plugs, wires and cap on a few days ago....not OEM stuff. Bosch platinum plugs.
??? brand on the new wires and cap.
he said "they" had a tough time with the distributor and had to take it out several times to get it right......I wonder if they knew what they were doing ???

What would make the #4 cyl. not fire well when the others seem to be firing well.....even tho they are not OEM ??

Are these compression test #'s OK or tolerable ?? I know they are more than 14 apart as per FSM.....

Could it be a bad injector ?? I have done several searches on this forum and still do not know what to make of this situation.

Is $4k an OK price ??

Any feedback is greatly appreciated ASAP..... if possible !!!

Many thanks.......I sold my dodge diesel 4x4 and the F350 4x4 so I could pay off some bills and hopefully get an affordable locked 80 !!!!!!

 

[Ebag333]

I would be suspicious of that low number. I don't recall the compression specs off hand, but I think that 165 is in range (or close to it), but the fact that it's significantly lower than any other cylinder to me would set off warning bells.

It could be a failing HG.

You can also do a leakdown test which may shed more light on it. I would also check the coolant for combustion gasses, and look under the oil cap to see if you see any milky substances.

If the HG is bad it's probably worth about $2k-$3k. Even if the HG was not bad I don't think I'd pay $4k for it.

 

[Pin_Head]

If the #4 plug was fouled, that would explain the misfire and it is something that you might be able to live with for another 25K miles with a hotter plug in the #4 hole. 165 PSI isn't low enough to cause the misfire by itself.

 

[4wdds]

My bet is on the injector. I would check that 1st.
Of course.........I'm always optimistic when it's someone else's rig

 

[Mo Rocks]

Thanks for the replies.

I am going back to the car lot after work today and check the firing order.
I did a search on it here and found 2 opinons
153624 AND 156324 ??? !!!

Will try both.

I do not know how to do a leakdown test. I will see if they will let me take it for the weekend and have a mech. friend help me w/ that.

I am also concerned about #4 being so low compared to the others.

How hard is it to R&R an injector ?? How much are they ??

Thanks for all the help.....

IT is 5:45 AM and time to go to the salt mine....

 

[Jack G. Nichols]

One of the cylinders on my 1993 was misfiring (I forget which) and traced it to a wire bundle at the back of the engine that had worn through. Once I insulated the bundle (thanks, Laird!) with some super duper helicopter wiring loom insulation, have been good to go. Anything might work, but I like to point to the extra special stuff.

Yea, doesn't take much to amuse me.

Hope yours is as easy as that.

 

[darnold87]

One of the cylinders on my 1993 was misfiring (I forget which) and traced it to a wire bundle at the back of the engine that had worn through. Once I insulated the bundle (thanks, Laird!) with some super duper helicopter wiring loom insulation, have been good to go. Anything might work, but I like to point to the extra special stuff.

Jack - can you tell me more about your fix. I've got a misfire occuring and would like to inspect the wire bundle at the back of the engine. Did you have to repair any wiring? Was one of them grounding out?

Thanks...

 

[Mo Rocks]

One of the cylinders on my 1993 was misfiring (I forget which) and traced it to a wire bundle at the back of the engine that had worn through. Once I insulated the bundle (thanks, Laird!) with some super duper helicopter wiring loom insulation, have been good to go. Anything might work, but I like to point to the extra special stuff.

Yea, doesn't take much to amuse me.

Hope yours is as easy as that.

Thanks, life would be a dream then.......

Thanks for the tip.......

I will try to check this out also when I go back to check the Firing order this PM .......I did not get to it yesterday.....had to work a bunch of OT unexpetedly

In the mean time I am putting up additional isulation (nasty $hit) in the attic while it is cooler up there...I have successfully procrastinated on it for years .... until now

 

[Mo Rocks]

[QUOTE: I don't think I'd pay $4k for it.[/QUOTE]

Well the 'cruiser Gods were with me and I got it out the door for under that......thanks for your inspiration....

One of the cylinders on my 1993 was misfiring (I forget which) and traced it to a wire bundle at the back of the engine that had worn through. Once I insulated the bundle (thanks, Laird!) with some super duper helicopter wiring loom insulation, have been good to go. Anything might work, but I like to point to the extra special stuff.

Yea, doesn't take much to amuse me.

Hope yours is as easy as that.

Looks like it is some wiring issues....ran a ton of Sea Foam thru it and no change. Got it home and cleaned it off with Purple Power and washed it off and it runs tike a new one. !!!! Must be a loose ground in the wiring somewhere......should be an easy fix, but could take hours to find the bad ground...ANY particular Ideas of where to start.
Injectors, ECM. Anywhere...Everywhere ??

I still have my hands full with the usual PM issues, antenna, clapped out front seats, rear window regulators.
At least it has lockers that work, good paint and NO RUST.

 

[Ebag333]

Check the main engine wiring harness near the EGR pipe (back of the engine). The EGR pipe tends to toast the harness and can cause damage.

I'd also replace all the plugs and wires with OEM. Some people have had problems with after market plugs and wires (even new).

 

[Mo Rocks]

Check the main engine wiring harness near the EGR pipe (back of the engine). The EGR pipe tends to toast the harness and can cause damage.

I'd also replace all the plugs and wires with OEM. Some people have had problems with after market plugs and wires (even new).

Thanks, I plan to replace all the non OEM plugs, wires, etc.

Will look at the wire harness.......THANKS !!!!!!

Got any ideas on how to fix the rear windows from sliding down 3-4 inches ?? They roll up slowly to a point and then stop. I can still hear the motor/regulator running and clicking until it hits the stop, but they stop short of being closed and then fall back down a few inches........ Got cardboard wedged in the channels to keep the windows from falling down right now......looks real nice.....
Got that Wal-Mart bling going on

 

[Ebag333]

Possibly the plastic gears in there are stripped out. No way to tell for sure without pulling the door off. Go ahead and do it, it's not tough.

 

[Dave 2000]

A sticking valve can cause a misifire and low compression, reading what we have so far I would swap an injector and see if the problem moves. Note that 165 is a tad low but within the realms of reality.

A HG often fails between two cylinders but not here it seems? Does it run hot, are the rad hoses rock hard indicating the cooling system is under a lot of pressure? Is the coolant clean, is the oil the right colour? Take a long plug lead with you and swap it out and see if it improves, try moving the wiring bundle at idle and see if there is any change.

Most misfires smooth out at at higher revs for a number of reasons so do not be misled by that.

regards

Dave

 

[Mo Rocks]

Possibly the plastic gears in there are stripped out. No way to tell for sure without pulling the door off. Go ahead and do it, it's not tough.

That is what I thought it might be.....I have R&R window motors and regulators a few times before, so I think I can handle it, I was just wondering if there were any tricks to it or anything unique to look out for. I hope whatever it is is not a bunch of $$....Thanks for the reply

A sticking valve can cause a misifire and low compression, reading what we have so far I would swap an injector and see if the problem moves. Note that 165 is a tad low but within the realms of reality. I thought a sticky valve might be in the list of possibilities. Will do an oil change and put some LUCAS oil treatment in it or small amout of ATF....it is a super high detergent....and cheaper than RESLONE (sp)

A HG often fails between two cylinders but not here it seems? Does it run hot, NO are the rad hoses rock hard indicating the cooling system is under a lot of pressure?No, I just discovered that the top radiator tank is cracked...not suprised, but then the system can't get very pressurised Is the coolant clean, It is a reddish brown...looks like old Toyota red is the oil the right colour?OIL looks fine...just looks like it might be time for a change...and they have some generic POS oil filter on it Take a long plug lead with you and swap it out and see if it improves, try moving the wiring bundle at idle and see if there is any change.
The skip is gone now that I sprayed it off with Purple Power cleaner and hosed it off....has been running great since yesterday. Drove it for an hour today. No skips at all !!!!!!
What I did find was that the oil pressure is at the 1/2-2/3 mark on the gauge with the RPM's up, but if I am at a light in Drive w/o the AC on, the RPM's drop to 600 and the oil pressure drops to 1/3...but picks right up with the RPM's.
Is this normal ?????????? for 165,000 miles. Maybe it is some ****py brand oil and filter. I want to try Shell Rotella 15-40 that I ran in my 5.9 Cummins diesel...That oil is great stuff
Most misfires smooth out at at higher revs for a number of reasons so do not be misled by that. It idles fine right now, and is smooth thru all RPM's, I think it must be an electrical issue...loose wire or bad ground if washing the engine off was what made it run better........??!! The water must be completing the ground connection or other circuit. I need to go over the entire engine connections/grounds to find it !! OMG !!!

I have not had time to work on it much to it today....I had to finish insulating the attic. That was part of the deal I had to make with the CEO/CFO in order to buy the 80 !!

Thanks for your reply....

regards

Dave

 

[Dave 2000]

Hmmm one of the few engines that run better when wet, normally it is the other way around!!

I would follow up on the wiring harness connections real soon if I were you.

In general if you switch on the A/C and or put it in gear (auto) then the ecu should sense this and increase the idle speed, I am not super savvy on the Landcruiser petrol engine but that is the norm IIRC, someone dive in here and help me please?

regards

Dave

 

[Mo Rocks]

The RPM's drop when it is in DRIVE and the AC os OFF....sorry if I did not make that clear.
It is OK when the AC is ON........the computer senses it and kicks up the RPM's accordingly.

BUT, the PO has the timing off, etc. So that might be part of the whole troublesome picture. This rig is the perfect candidate for a lot of good old PM work.....!!!

I need to call 1-800-CDAN soon !!!!!......BTW, what is his # ???

I just got a FSM for it on evilbay....so maybe I can get some much needed reference material and some specs !!!!!!!!!

Thanks !!!!

 

[Ebag333]

i need to call 1-800-cdan soon !!!!!......btw, what is his # ???

1-800-432-6668

 

[Mo Rocks]

1-800-432-6668

Thanks for the #......I will be calling him soon for a lot of goodies