dreamer1q

First of all, hello everyone, I have been a stalker on here for a number of years. I have owned 3 LS400's and 2 LS430's. Currently I have two LS400's in my barn just for parts, and my daughter has a 1994 LS400 that I gave her at college.

I have her 1994 LS400 in the garage this week, fixing a power steering leak (typical), new valve cover gaskets, and giving it a tune up. When the car rolled into the garage, it ran fine, had only a TRAC light which I knew it had and was throwing zero codes.

I proceeded to pull the valve covers, plugs, wires, caps, and rotors. I put all of this back together with new parts, I did remove the throttle body to do the valve covers. Fired the car up and it threw a code 13. I looked up the code 13 on the Lexls.com web site, and proceeded to trouble shoot the issue. I found the crank sensor wire was cut up, not through, but chewed. I cut the sensor pigtail off of my 1993 parts car, and soldered it on. I check the continuity on the Crank Sensor (1089) and the repaired wire (676). I then put it back together again, and fired it up. Still a code 13 after clearing the codes.

Next I tore it down again, and replaced both the cam sensors with know working ones off of my 1993 parts car again. For reference, the 1993 parts car is my personal old LS400 that I totalled less than 2 months ago with a front end collision. The car still ran but the suspension was wrecked so I just bought a LS430 for myself and kept the 1993 LS400 for parts for my daughters car. Anyway, I installed both the cam sensors off of my parts car, checked the continuity of the sensors (1086 and 1118), and checked the wires on the car (673). I also changed the coils with know good units, put the plug wires back to the factory units that were on the car, and even changed the caps and rotors back to the used ones that were on it. Just to eliminate all things. I also pulled both ignitiors off of my 1993 parts car and put them on just in case.

So now I have new cam sensors, ignitiors, the original caps and rotors and new coils. Fire up the car again after resetting codes, and I have a code 13 again. I am at my wits end, and honestly I have to get her on the road back to Cinncinati from Nashville. So I am under the gun.

The only other thing that I can find or think of is the timing. But I have a SERIOUSLY hard time believing that the car jumped timing sitting on my garage floor. This is something I plan to confirm in the morning by finding TDC and checking it from there.

Can ANYONE give me something else that might be an issue here? I am geuinely stumped and I have NEVER been stumped like this before. There is no reason that I should be getting a code 13 out of a car that ran fine coming into the garage for a tune up.

HELP PLEASE.

Gene01

Sorry that I can't help with your Code 13 problem, but I am very curious about how well it works to use an LS430 as a parts car for a 1994 LS400.

dreamer1q

Ninja edit Gene

aomdedude1

Okay, I have an idea for you so that you can verify that it is NOT the wiring that is the issue. Hopefully you are familiar with a multimeter. Set your multimeter to continuity. I like the meters that beep when you have continuity.

Make sure to disconnect the battery as not to fry any electronics accidentally. Disconnect your CPS and CAM sensors and also the 22 pin ECU connector. All the wiring from the crank and cam sensors go to the ECU via the 22 pin connector. You have to test continuity between the ECU connector and the Harness side connector of the CPS and CAM sensor connectors one at a time.

I took the wiring diagrams and highlighted the wires you need to test to verify that the wiring is intact.




After you disconnect all the sensors, just take a looooooong jumper wire and put one end in the harness side crankshaft position sensors BLACK wire. Take the other end of your long jumper wire and your multimeter and test continuity between your jumper wire and the black #5 (NE) wire.

There are a few black wires so make sure you have the correct one.

Do the same for the rest of the colors.

If you get continuity, then your wiring is NOT the issue.

Hopefully this helps you out.

I included a picture of my ECU to help you locate the appropriate ECU harness connector to test. (22P)


I think the obvious issue here is going to be figuring out what wire at the ECU harness connector you need to test.

aomdedude1

Ahaaa.... I dug up the solution to knowing what connector to test.

Here is the diagram that labels all the ECU connectors. (original PDF attached)

LScowboyLS

code 13 is almost always one of the following:

● bad cam sensor
● bad crank sensor
● bad wiring to one of the 3 sensors above
● jumped time (usually just 1 tooth and on just one cam)
● failing ECU capacitors

dreamer1q

Thanks for the help guys.

I did pull the plugs today again, and the plugs running off of the driver side low coil were soaked. Yet I verified spark through the remove the wire and shock yourself test.

Going to try and find the problem in the coil or wiring first. Then I will dig into the lower dash as posted above (big thanks for that btw).

She is taking my LS430 back to Cinci today, so now I have to fix it or I have no wheels. LOL....damn kids.

aomdedude1

LOL

.... I'll let you stick to doing that test while I sit back and watch....


Man, sucks your kids have your ride new now!

dreamer1q

She felt bad about it, but I am sure she is loving it. I just bought the thing like a month ago, 2004 LS430 UL....so she isnt hurting on the ride back. LOL

I did find an issue, but I need some more help if possible.

The coil plug going to the wiring loom on the top coil gave no resistence, so I am back tracking that right now looking for breaks. That is issue one.

However, the plugs that were wet are the plugs running of the second coil, the low side driver side one.

So what I am trying to find right now is the resistence that should be on the lines going to the coil from the wiring looms. That way I can verify which one, if not both, that are messed up.

Having no resistence on the top one is obviously an issue, but it doesnt explain why the plugs running of the other coil were wet.

Anyone have those values laying around?

aomdedude1

Check your PM's for the full PDF.

Here is a pic with all the coil and high tension cord resistance values:

dreamer1q

I give up. I have tested and retested everything and I can't find the issue. Everything checks out, all within values, all new parts, timing is right. I don't get it

500 bucks to the first person who can fix it, otherwise off to the dealership Monday. This sucks big time. Not exactly the best time of year to have an out of pocket expense like this one.

Thanks for the help guys. Really do appreciate the attempts

stephen18

well, does it misfire or run well?

LScowboyLS

so you are saying that plugs 1, 4, 6, and 7 in the diagram below were the only ones wet? - if so, then this is very easy, you are down to one coil, 1 igniter, a couple of wires associated with that coil and igniter, one cap and one rotor, or the ECU that could possibly be the problem! (see diagram below) - the problem has to be on circuit IGT1 or IGF1 or else downstream of it

my paypal address is ************* AT yahoo DOT com

aomdedude1

LMAO.... I do hope you get it fixed!~ If it worked before, I'd put money on it being electrical in nature too. (obviously )


Let us know what turns out being the problem!

dreamer1q

I ran the jumper test this morning.

I checked every single pin out on the plug on the ECU that was indicated in the post above. I checked each pin against all 6 pins on the cam sensors and the crank sensor. The only hit I got was on the #5 line on the crank sensor, everything else was dead. I did have the coils unplugged, but I thought this went direct to the ECU, so that shouldnt matter for continuity.

At this point I am trying to decide if I can do a wiring harness off of the parts car, or if it is just time to swap the drivelines like I had planned on doing in the future due to lower miles on my parts car. Is the harness swap a breeze or is it going to be just as much as swapping engines? Looks like a lot of tear down to get a wiring harness off.

I am so screwed right now....

Cowboy, I have not done the bypass that you sent yet, figuring that the continuity check would suffice to make sure things were even getting that far, and becuase I have been shocked by both coils already. So they must work.