2003 Land Cruiser 100 Series HELP! Wits end

[ThePang]

Ok Everyone long time lurker and first time poster.

I have owned a few LCs and 5 Gen 3 4runners and NONE have given me the hard time that my Current 2003 LC is giving me.

Vehicle: 2003 LC 189k miles Blue on Tan and in fantastic shape. Its a Cali and now Hawaii car and has had regular maintenance. I had NO problems with the LC for the first 5k miles I drove it after I acquired it from the original owner 7 months ago.

The timing belt had not been done for 11 years and 70k so I had my local INDI shop do it. I also had them do the brakes, rotors while there. Also they changed out the front door speakers as I didnt have the time to do them myself.

My issues started soon after when my wife was driving it stated to skip, sputter, miss etc until if died on the side of the road. I went with my scan tool to see if I could see what was going on . I cleared the Miss fire codes and drove home 40 miles without much issue. But it did begin to sputter and stall once while I was driving. At this point I had the indi shop look at it and they said it was the Cam shaft position sensor which made sense to me and was consistent with the symptoms in my mind.

The LC ran fine for a bit after that until is stalled without notice 8 miles from my house all up hill. I was not able to restart the vehicle but was able to coast it all the way to the shop near my home, which is the same shop that had been doing the work. The lead mechanic whom i have dealt with many times and trust could not find out what the issue was. So at this point I had unlimited time and decided to figure it out myself. I have read every forum under the sun on this sight and others trying to determine the issue.

I began getting misfire codes so i decided to change all the plugs and coil packs with denso original equipment. Ran fine for awhile but the problem persisted.

I checked the fuel delivery at the filter and it felt strong but I decided to change out the fuel pump, sock, and filter. Ran great for 700 miles then the problems came back.

I then thought it could be the sub woofer which i replaced over powering the amp and causing the cpu to have issues, so i unplugged the amp all together and it once again ran fine for a long time but the problem came back.

I have checked the key fob, the fuel pump relay and added the 25 amp fuse to the box.

The fuse box is clean and does not seem disturbed or have corrosion.

I have replaced, checked, fixed everything I can think of. The car will start and run fine but then begin to sputter and miss quite bad at points, and at other points it runs perfect. I do not believe it to be a mechanical issue as the engine does not leak, i checked compression, did head gasket check, all good.

I am at my wits end and no one seems to know what the issue is. The vehicle does not have rust and the ground connections all seem good. I have not found any frayed or damaged wires either.

PLEASE HELP!

 

[hickuptruck]

replace your maf

 

[ThePang]

I did take out the MAF and clean it. It looked fine but i guess it cannot hurt to replace it. At this point Ill try anything and willing to throw money at it to an extent.

 

[ThePang]

Also when the LC is running fine it does not throw any codes. But when it starts to miss etc it will throw several random codes. Including Misc miss fire codes.

 

[abuck99]

Your thread title said WitsEnd and I thought Mud vendor

You can test MAF, but eventually they do diminish and fail. Clean only with MAF spray, and disconnect battery before disconnect MAF -leave for 30min. It will take several drive cycles to relearn parameters (idle will seem high) before you see improvement.

 

[ThePang]

@abuck99 Thanks, I did exactly that during this whole process. I cleaned it with some maf cleaner and disconnected the battery also. I just ordered a new maf so we will see how it goes. I welcome any and all recomendations!!

 

[trdcorolla]

Are the misfires happening on the same side of the engine? If so maybe your timing is off.

 

[GOLIGHTLY]

Agreed on the MAF front… run into that on other vehicles and threw very similar symptoms. As far as car parts go, a very cheap/easy gamble.

Perhaps a question meant to be fielded by others in here, but is there any fuel quality risk on The Islands? Just curious if there’s any reason to believe fuel delivery or composition could at all play a role.

 

[UncleJakeNZ]

While you wait for a new MAF I'd also check the simple things that many who have scanning tools forget to do:

e.g.

• Is rain water getting into the fuel.
• Run the engine with the bonnet open in the dark and look for any electrical arcing
• Make a note of weather, air temps and fuel level every time the motor plays up

I had a similar problem years ago and it took almost a year to find... and was a cracked wire in the ignition system... but that was not a Land Cruiser so won't bore you with the details

 

[KliersLC]

I'd also look at the crank position sensor and it's wiring. It is kinda hard to see, but many mechanics do not correctly reinstall the wiring retainers and it tends to rub on the serpentine belt, causing issue just like you describe. The good news is that if that is indeed the case, it is simple, cheap, and your mech should comp you the labor as it was their mistake....

 

[wildsmith]

I'd double check the ECU fuse. There's a thread about it on here. IIRC the fault is internal, it was on mine, so it can look aok, but not be. The thread has some bypass tips you could use to prove / disprove if that's the problem.

 

[graveling]

I'd also look at the crank position sensor and it's wiring. It is kinda hard to see, but many mechanics do not correctly reinstall the wiring retainers and it tends to rub on the serpentine belt, causing issue just like you describe. The good news is that if that is indeed the case, it is simple, cheap, and your mech should comp you the labor as it was their mistake....

Agree with this. I recall having a similar issue when I did my first timing belt on my 4.7 Tundra, although I think the code made it pretty clear what was going on. Make sure all electrical connectors are tight.

 

[ThePang]

Ok thanks for all the replies thus far. I have not seen or heard any arcing as i have let the LC idle in for hours on end trying to find the issue.

There does seem to be some relation to fuel, or the fuel system. At one point during this "adventure" i began to think it was fuel related. I felt it may be the fuel pump not giving enough fuel after start up. The issue does seem to somehow be fuel related as issues would arise after fueling, or removing the fuel cap. It always filled with Premium but usually Costco fuel as its the cheapest you can find on the island. im gonna go out and look at the crank sensor again now....which i have already done but maybe a closer inspection is in order.

 

[graveling]

When my fuel pump died in my Tundra (same engine / same pump), it didn't display the symptoms you describe. One day I went to start and it would not catch at all. One trick to get you home in case the pump goes is to beat on the bottom of the tank with a rubber mallet (anything could be used that doesn't damage the tank). Sounds nuts, but sure enough it worked and I was able to get the car home! From what I recall, they said that carbon builds on the pump motor which can stop it from turning. Beating on it moves the motor enough to get a good connection. It's a crap shoot if you stop again though.

I changed my fuel pump in my 99 LC with 170K when I bought it a year or so back. Unlike the Tundra (my wife still give me s*** for making her hold the tank while I hooked up the straps), you can access it by removing the 2nd row seat. 2 banana job and worth the peace of mind.

 

[ThePang]

@graveling thanks, yea i have already replaced the FP and the filter...

OK so i just went out took the skid plate off and was looking around for possible issues once again. The Crank sensor and wires all looked good... everything else was dry and seemingly no issues... then I found a sensor which appears to be an aux coolant sensor? its in front of the rad and inline with a coolant line. Looking closer the wires for the plug were exposed and there was water/coolant running straight down the line and collecting in the wire shielding! the senson and wires were soaked and seemingly the wires were sitting in some of the coolant or water collecting inside the shielding/wire cover.

I unplugged and cleaned both sides with some electric cleaner and fixed the wire cover issues. I assume it is possible this was causing my issue as any wire contacting water and or sitting in it cant be good haha... so fingers crossed we have a solution.

 

[Devils Paw 80]

Perhaps a question meant to be fielded by others in here, but is there any fuel quality risk on The Islands? Just curious if there’s any reason to believe fuel delivery or composition could at all play a role.

@graveling thanks, yea i have already replaced the FP and the filter...

OK so i just went out took the skid plate off and was looking around for possible issues once again. The Crank sensor and wires all looked good... everything else was dry and seemingly no issues... then I found a sensor which appears to be an aux coolant sensor? its in front of the rad and inline with a coolant line. Looking closer the wires for the plug were exposed and there was water/coolant running straight down the line and collecting in the wire shielding! the senson and wires were soaked and seemingly the wires were sitting in some of the coolant or water collecting inside the shielding/wire cover.

I unplugged and cleaned both sides with some electric cleaner and fixed the wire cover issues. I assume it is possible this was causing my issue as any wire contacting water and or sitting in it cant be good haha... so fingers crossed we have a solution.

View attachment 2866066

What's the source of coolant leak? Island gas is fine...

 

[G-Cat]

Hopeful that you found and fixed your problem.

To add, and since not mentioned, same symptoms on my 98 4Runner were due to a bad fuel injector. Had them all replaced and no issues for 40K miles…

 

[ThePang]

WELP... Just drove it for about 45 miles mostly without issue. One little skip which felt like a mis fire and then on the way home it did what it normally does after about 45-60 miles of driving. This time it was ONE major Skip, shudder, while traveling about 55mph on flat smooth road, but this time it did it once and that was it? Normally it will start to shudder like that pretty badly and sometimes cut off completely. If i shift it out of D and into 4 or 3 the prob seems to happen less?

I am hopeful that the MAF fixes the issue.

@G-Cat I have considered the fuel injectors also may just do that job to baseline the entire rig. its too nice to abandon at this point and I bought if for a great deal sooo onward we move.

Here is the trouble maker

 

[G-Cat]

@boofaz is having similar issues. Thread won’t help, but maybe you two can compare notes:

For Sale - 2000 LC with cylinder misfire $5k

I have a 2000 LC with 230k ish miles. I have replaced a ton of parts most listed below with oem, and I'm in the process of purchasing a newer 200 series. I've lost the drive to chase this last misfire issue and want to pass this project (any cruiser this old is a project) on to someone else...

forum.ih8mud.com

 

[UncleJakeNZ]

Consider replacing the fuel filler cap if you're certain there's no water in the fuel