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Problem On Starting 99 Ls400


r_ls400
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I have ths 99 LS400 for 10 years and put 84K on it. I was a frequent traveler in some of the earlier years. It's a good car and I can't recall any single issue with the car. I drive 20 miles (50% freeway) daily recently.

The problem started a month back. I put in a new battery after some checking upon 1st couple of starting failure. I drove 6 hours on I-5 to LA, did some local driving the next day and the problem came back the 3rd morning on the first attempt of the day. It wasn't too cold there and then. After jumping, it went problem-free for the rest of the week-long trip till a week later. I had an auto parts store tested the battery. Per the technician, alternator was OK and the battery was OK too but needed some charging. The easier way was for me to blame on the weak battery. I returned the 1-month old battery and put in a "better" battery a week ago.

The problem came back again this PM. The starter gave the click but nothing else. I tried to charge the battery for 30 mintues with a heavy duty power supply (14.0V, 9A and dropping). The same charging worked several times before, but not today. It finally started after I jumped and battery and gave the other car a good stepping on the pedal.

It's about time to send the car to the shop. Beside my curiosity, I am preparing myself in my talks to the mechanics. What can be the cause of the problem beside the battery and alternator? The alternator was giving from 13.7 to 14.4V when engine is running and everything is ON in my own tests.

I have searched the forum for some education but still don't have any solid idea. Please advise if anyone can. Thanks a lot.

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Sounds like a starter. Sry.

Is the starter taking more current to start the more you wear and tear it over time? This was a once a week problem. The starter did give a week of good starting in-between jumpings.

Things all get old and useless. It's been 10 years and I'll be happy to put in a new starter if that's the case.

Thanks.

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It's the starter probably. It's not closing the high current contacts in the solenoid. Easy fix once the starter is out. Next time the car doesn't want to start, turn on the headlights. If they are bright, the battery is charged. That means the starter. In the old days one could crank the engine with the lights on and get further info as to starter current draw, but modern cars don't allow that as the headlights are turned off when cranking. At least I believe they are on the LS.

Just cycle the key several times and the starter should engage for a few more times before you can get it fixed properly.

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So it's just the dreaded click-nothing symptom? If so, then it's the starter. The solenoid contacts aren't passing enough voltage to start the car. I had the same thing happen recently on my 95 after it started to cool off. I replaced the contacts and plunger myself and all is better. The problem on my 95 is that I couldn't get the lower EGR pipe disconnected from the rear coolant bridge so I did it with the starter in place. (Shh don't tell anyone). I believe your 98 doesn't have the same EGR setup so it should be easier but it's still a weekend job.

I bought the Repair Kit from Adam at Nations Auto Electric: http://www.nationsautoelectric.com/densoparts.html

Here are a few links that helped me out:

http://www.lextreme.com/dx-starter.html

http://www.lextreme.com/starter.html

http://www.clublexus.com/forums/ls400-foru...ory-by-bdr.html

http://us.lexusownersclub.com/forums/index...showtopic=49611

http://www.4crawler.com/4x4/CheapTricks/Starter.shtml

Photo of Lower EGR Pipe connected to the Rear Coolant Bridge on a 95:

post-13297-1232262285_thumb.jpg

Photo of starter with armature assy removed:

post-13297-1232262427_thumb.jpg

Photo of the new contacts installed in the starter solenoid (with the starter in place):

post-13297-1232261727_thumb.jpg

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  • 2 weeks later...
So it's just the dreaded click-nothing symptom? If so, then it's the starter. The solenoid contacts aren't passing enough voltage to start the car. I had the same thing happen recently on my 95 after it started to cool off. I replaced the contacts and plunger myself and all is better. The problem on my 95 is that I couldn't get the lower EGR pipe disconnected from the rear coolant bridge so I did it with the starter in place. (Shh don't tell anyone). I believe your 98 doesn't have the same EGR setup so it should be easier but it's still a weekend job.

I bought the Repair Kit from Adam at Nations Auto Electric: http://www.nationsautoelectric.com/densoparts.html

Here are a few links that helped me out:

http://www.lextreme.com/dx-starter.html

http://www.lextreme.com/starter.html

http://www.clublexus.com/forums/ls400-foru...ory-by-bdr.html

http://us.lexusownersclub.com/forums/index...showtopic=49611

http://www.4crawler.com/4x4/CheapTricks/Starter.shtml

Photo of Lower EGR Pipe connected to the Rear Coolant Bridge on a 95:

post-13297-1232262285_thumb.jpg

Photo of starter with armature assy removed:

post-13297-1232262427_thumb.jpg

Photo of the new contacts installed in the starter solenoid (with the starter in place):

post-13297-1232261727_thumb.jpg

Some interim feedback and some additional question/confirmation.

I worked with a neighborhood mechanic who drives a '90 LS400 himself. After some testing, he thought the starter was alright but didn't like the unstable charging voltage (dipped below 13.8V at times) of the alternator and replaced it. He checked the wiring and electrical system and concluded there is no leakage problem. Remember this has been a "once a week" starting problem. Things went well for a week or so. Then, the click-and-nothing came back one morning but I was able to start the car on the 2nd attempt. I went over to the garage and asked him to check again. He started the car several times while watching the voltage meter. The battery dipped down to 11.5V the lowest and he thought it was still far above the 9.6V threshold. We decided to keep watching and will target the starter the next time. 3 days later, I has the same thing came back - click-and-nothing on the 1st attempt but started nicely on the 2nd trial right afterwards. After the 1st starting of day, car started ncely for the rest of the day even with some cooling down periods in-between.

My question now is "Will changing/rebuilding the starter take care of this problem?". Is there anything else between the key switch and the starter (something like relay?) that I need to consider before the innevitable?

Thank you all for the responses and sharing.

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My question now is "Will changing/rebuilding the starter take care of this problem?". Is there anything else between the key switch and the starter (something like relay?) that I need to consider before the innevitable?

You can check out this article: How To Diagnose Faulty Starter

I'd hate to be the one to changing/rebuilding the starter will fix the issue then it turn out to be something else. I only had my car about a month before the problem started. But it had significantly cooled off by then. Maybe temperature affects the voltage/amps/resistance the contacts in the solenoids pass through them. While not from a LS400, this thread has some great pictures showing the difference between new and worn contacts.

http://www.cumminsforum.com/forum/98-5-02-...nt-2nd-gen.html

With the surface area/mass of the contacts being greatly reduced on the worn contacts/plunger, it's not enough to keep the plunger in contact with the contacts to drive the starter, hence the click sound. It makes sense to me at least.

After the 1st starting of day, car started ncely for the rest of the day even with some cooling down periods in-between.

If temperature does play a part, it takes a long time for the starter to cool off because it's in the valley between the cylinders. This could explain why it works better the rest of the day. Even with your "cooling down periods in-between" the starter is still warmer than when it sits overnight.

I think I've seen other threads were the starter causes an increased draw in amps which could explain the voltage drop you're seeing. Again, this could be because of the reduced mass of the contacts. I'm not an electrician but I do know that you need larger guage wire to handle higher loads. To me, as the contact wear the guage goes up (smaller) and is able to handle less load.

Ooooh..... here is another great thread I found with lots of pics of the contacts:

http://www.expeditionportal.com/forum/showthread.php?t=12746

Good Luck!!

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Your neighborhood mechanic can mess with the charging circuit all he wants. It won't fix it. These cars have trouble with the contacts in the starter - that's why it's intermittent. If it was the battery a simple load test would confirm it. If it was the alternator an output test - not voltage - would confirm it. It's not the wiring - the solenoid is trying to trip - so the wiring is fine. "Voltage threshold" ? - what, he gave up a job a NASA? Of course the voltage is good - the starter can't draw enough current to drop the voltage because the contacts are fried!

It's the starter. Get on to it.

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"Voltage threshold" ? - what, he gave up a job a NASA? Of course the voltage is good - the starter can't draw enough current to drop the voltage because the contacts are fried!

It's the starter. Get on to it.

Damn I love a dose of sarcasm...

:lol:

SRK is my hero.

P.S. I would get on that starter, yo.

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My question now is "Will changing/rebuilding the starter take care of this problem?". Is there anything else between the key switch and the starter (something like relay?) that I need to consider before the innevitable?

You can check out this article: How To Diagnose Faulty Starter

I'd hate to be the one to changing/rebuilding the starter will fix the issue then it turn out to be something else. I only had my car about a month before the problem started. But it had significantly cooled off by then. Maybe temperature affects the voltage/amps/resistance the contacts in the solenoids pass through them. While not from a LS400, this thread has some great pictures showing the difference between new and worn contacts.

http://www.cumminsforum.com/forum/98-5-02-...nt-2nd-gen.html

With the surface area/mass of the contacts being greatly reduced on the worn contacts/plunger, it's not enough to keep the plunger in contact with the contacts to drive the starter, hence the click sound. It makes sense to me at least.

After the 1st starting of day, car started ncely for the rest of the day even with some cooling down periods in-between.

If temperature does play a part, it takes a long time for the starter to cool off because it's in the valley between the cylinders. This could explain why it works better the rest of the day. Even with your "cooling down periods in-between" the starter is still warmer than when it sits overnight.

I think I've seen other threads were the starter causes an increased draw in amps which could explain the voltage drop you're seeing. Again, this could be because of the reduced mass of the contacts. I'm not an electrician but I do know that you need larger guage wire to handle higher loads. To me, as the contact wear the guage goes up (smaller) and is able to handle less load.

Ooooh..... here is another great thread I found with lots of pics of the contacts:

http://www.expeditionportal.com/forum/showthread.php?t=12746

Good Luck!!

Thanks again. I don't know why the mechanic likes my starter that much and it's time for me to insist on it. I guess the alternator and starter were both marginal and it's time to get to the other one. I happen to be an electrical person and things like worn contacts and increased resistance all make sense to me. Too bad that a lot of things are not "plug'n play" in the auto world, especially when we all know we need to replace some experienced parts at some intervals.

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