Go Back   Club Lexus Forums > Lexus Model Forums > SC Models > SC 400/300 > Performance & Maintenance
Sign in using an external account
Register Forgot Password?

SC400 no power, burning, rough idle

Reply
 
 
 
 
Thread Tools Search this Thread Display Modes
Old 08-09-14, 03:03 PM   #1
Penthos
Driver School Candidate
Trader Score: (0)
 
Penthos's Avatar
 
Join Date: Aug 2014
Location: Texas
Posts: 17
Ares1105 Penthosmusic Penthosmusic
Default SC400 no power, burning, rough idle

***UPDATE*** I had all the spark plug wires/spark plugs/ignition wire harness replaced. Both coils test to spec. Now the car starts but only if I give it gas for about 5 seconds. However there is NO FORWARD DRIVE. if I put it into any forward gear it just revs as if in neutral... If I out it in reverse, it basically accelerates on its own and is hesitant. I asked a professional about it and he said it sounds like the torque converter... But I wanna make sure it can't be ANYTHING else before I get that replaced too.

****END UPDATE****

Hey guys. BEFORE YOU FLAME ME I did search through the forum and found some possible reasons for the car's behavior but I haven't had a chance to get it worked on so I am looking for opinions.

I bought A 1993 SC400 YESTERDAY with 207k miles. I'm not a super-savvy car person just yet (this is my second car) but I looked over the engine and tested it out and it seemed okay. Then as I was driving I accidentally hit the "power" ECU switch, then switched it back. I don't know if that had anything to do with it but it soon after it started losing power. I would be revving but little acceleration. I stopped and turned it off to let it cool, then after that there was no acceleration at all. I researched CL And see that many people found it was a coil. I didn't have any kind of testing gear so I went to autozone, they had one coil left compatible with my car. I came back and lifted the hood and noticed that passenger side coil was jimmied up with electrical tape. Come to find out that the 2-pin connector was missing the clip and taped down into the connection. I tried to change the coil out but no Dice. Same thing. Then I tried to change the driver side coil with the one I had taken out and the car would start but the engine quickly died. So I'm not sure if it's the driver side coil or the connectors/wires or the distributor caps or if it's something else. Any help would be appreciated.

LLike I said, I'm not super car savvy but I'm learning as I go.
This ad is not displayed to registered members.
Register your free account today and become a member on Club Lexus!

Last edited by Penthos; 08-16-14 at 08:39 AM.. Reason: Update
Penthos is offline   Reply With Quote
Old 08-09-14, 03:27 PM   #2
t2d2
Lexus Test Driver
Trader Score: (3)
 
t2d2's Avatar
 
Join Date: Apr 2014
Location: Oregon
Posts: 919
Default

If it's the connector, Drift Motion carries the replacement. I just installed mine on the pass. side last week, as my old connector was pretty busted up. Part #DM1575. You'll probably need to order the repair wires, as well. I ended up being able to re-use my wires since the old connector disintegrated and I could pull the old pins out, so no need to splice and solder. Just as well, since I later found one of my other needed connector replacements through Toyota, and they wanted $14 per wire instead of DM's $2 per! The spares came in handy.

If it's not the connector, I'll have to leave it up to someone more knowledgeable to troubleshoot.
__________________
'94 SC400 Factory Frankenstein: '00 RX300 steering wheel, '93-96 GS300 speedo/tach needles, '98-02 GS4xx wheels, Prius lug nuts (eco friendly!) ... LS400 calipers denied wheel clearance for take-off.
Performance: Alternative BFI (BeeFI?), A/T Solenoid Bypass, M2/Manzo axleback exhaust (awaiting mid-pipe resonator delete), 2-Tone Driver's Seat ("performance" as measured by the butt test).
t2d2 is offline   Reply With Quote
Old 08-09-14, 07:52 PM   #3
Penthos
Driver School Candidate
Trader Score: (0)
 
Penthos's Avatar
 
Join Date: Aug 2014
Location: Texas
Posts: 17
Ares1105 Penthosmusic Penthosmusic
Default

Quote:
Originally Posted by t2d2 View Post
If it's the connector, Drift Motion carries the replacement. I just installed mine on the pass. side last week, as my old connector was pretty busted up. Part #DM1575. You'll probably need to order the repair wires, as well. I ended up being able to re-use my wires since the old connector disintegrated and I could pull the old pins out, so no need to splice and solder. Just as well, since I later found one of my other needed connector replacements through Toyota, and they wanted $14 per wire instead of DM's $2 per! The spares came in handy.

If it's not the connector, I'll have to leave it up to someone more knowledgeable to troubleshoot.
Is it pretty easy to install? I just don't wanna f*** anything up lol. I think I need the wires too. I'm trying to go with the cheaper things first before I start looking at IACV AND MAF. I also read that I should check the fuse for looseness or corrosion as that could be cutting power to the ECU, but I am not around the car and won't be for a few days.
Penthos is offline   Reply With Quote
Old 08-09-14, 10:24 PM   #4
t2d2
Lexus Test Driver
Trader Score: (3)
 
t2d2's Avatar
 
Join Date: Apr 2014
Location: Oregon
Posts: 919
Default

If you don't have to cut and splice, it's quite easy. The key is disassembling (aka destroying) the old connector without damaging the wire pins. Mine basically disintegrated while trying to pop the tabs loose, so that was remarkable straight forward. From there, you just push the pins back into the new connector, being careful to orient them the same as before.

Now, if you can't salvage the wires like that, you'll need to pick a spot to cut them and solder the new ones into place. That's significantly less easy, but it depends a lot on your skill level. I had to do that yesterday on my single-wire coolant temp sensor (to the gauge cluster, I believe, as opposed to the two-wire one to the ECU), being the third of four damaged connectors/wires I found within a few inches of each other. That one had a bare wire in addition to broken connector, so I had to cut and solder it. My soldering skills are feeble at best. I was super careful to get the wires cut to the right length, heat shrink tubing on first, protective sheath split far enough down to have room to work, other wires tucked out of the way, etc. I got the wires nicely soldered, only to realize the heat from the soldering iron had been too much for the heat shrink tubing and it could no longer be slid down into position. Argh! I managed to salvage it, but I was close to throwing my soldering equipment in the trash.

Check your TPS adjustments, as well. I've done all the recommended IAC/MAF stuff and it's had no effect, but small tweaks to the TPS can have dramatic impact. I've yet to manage to get it just right, however.
__________________
'94 SC400 Factory Frankenstein: '00 RX300 steering wheel, '93-96 GS300 speedo/tach needles, '98-02 GS4xx wheels, Prius lug nuts (eco friendly!) ... LS400 calipers denied wheel clearance for take-off.
Performance: Alternative BFI (BeeFI?), A/T Solenoid Bypass, M2/Manzo axleback exhaust (awaiting mid-pipe resonator delete), 2-Tone Driver's Seat ("performance" as measured by the butt test).
t2d2 is offline   Reply With Quote
Old 08-15-14, 01:40 PM   #5
Penthos
Driver School Candidate
Trader Score: (0)
 
Penthos's Avatar
 
Join Date: Aug 2014
Location: Texas
Posts: 17
Ares1105 Penthosmusic Penthosmusic
Default Update

Okay so I had the ignition wire harness/spark plugs/spark plug wires replaced. Tested both coils and they are to spec. The car will start but I have to give it gas and it will NOT shift into drive. I'll manually shift to drive and it doesn't light up on cluster and no power. If I shift to 2 or L, it lights up but no power. I shift to reverse, it will reverse but only on a heavy foot. When I turn the car off I can hear the fuel pump pretty loud from the left backseat panel. I don't know what it could be now. Could it be a burnt transmission solenoid? I even read it could be a dying battery but that's hopeful. Please help!
Penthos is offline   Reply With Quote
Old 08-16-14, 08:40 AM   #6
Penthos
Driver School Candidate
Trader Score: (0)
 
Penthos's Avatar
 
Join Date: Aug 2014
Location: Texas
Posts: 17
Ares1105 Penthosmusic Penthosmusic
Default

Crap I hope it's not the tranny
Penthos is offline   Reply With Quote
Old 08-16-14, 08:49 AM   #7
t2d2
Lexus Test Driver
Trader Score: (3)
 
t2d2's Avatar
 
Join Date: Apr 2014
Location: Oregon
Posts: 919
Default

I wish I could offer more help, but you're outside my area of knowledge now. I would take something that potentially serious to a mechanic.
__________________
'94 SC400 Factory Frankenstein: '00 RX300 steering wheel, '93-96 GS300 speedo/tach needles, '98-02 GS4xx wheels, Prius lug nuts (eco friendly!) ... LS400 calipers denied wheel clearance for take-off.
Performance: Alternative BFI (BeeFI?), A/T Solenoid Bypass, M2/Manzo axleback exhaust (awaiting mid-pipe resonator delete), 2-Tone Driver's Seat ("performance" as measured by the butt test).
t2d2 is offline   Reply With Quote
Old 08-16-14, 09:06 PM   #8
SC400slide
Lexus Champion
Trader Score: (5)
 
SC400slide's Avatar
 
Join Date: Apr 2012
Location: In Recovery mode
Posts: 2,919
Jonathan Hoppman SC400slide Jonathan Hoppman Jonny Hoppman
Send a message via Skype™ to SC400slide
Default

Usually, on SC's that is, tranny issues are either two things. Shift solenoid(s), or the ECU. I suspect the ECU if nothing has been done to it. The way this problem escalated would make perfect sense that the ECU has been busy leaking the gel from the capacitors. If you have already replaced the unit, make sure it is a tested working ECU not some used worn ot leaking unit. Believe it or not, the ECU causes this and many more issues. It's the brain to the entire vehicle.

So, if you haven't already, pull out the ECU, have it rebuilt but somebody who knows something, and see what happens. My money is on the ECU, replaced or not.

I dont think the torque converter would cause any issues like that. In the rare occasion that the converter fails, it would be a fin breaking, which is highly unlikely. TC's just dont break. They are (for the most part) a closed system. They just circulate the ATF throughout the tranny.
__________________
1992 Lexus SC400,1995 Lexus SC400, 1996 Ford Explorer, 1971 Oldsmobile Cutlass SOLD, 1992 Ford Explorer SOLD
Lebo Boh tak miloval svet...
Apple Device Intellegentsia
TLN# 49 "Burnt Brownie"
SC400slide is offline   Reply With Quote
Old 08-16-14, 09:06 PM
 
 
 
 
Reply

Tags
burned, fuel, idling

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Lexus RX350 3.5L NAP (Made in Canada) 2008 Spark Plug Change rxs0 RX - Second Generation 29 07-05-14 10:40 PM
washed my engine, now guess what........ grumpi300 Performance & Maintenance 67 05-15-14 08:29 PM
No spark on driver side plugs kohatsu LS400 17 04-29-14 11:48 AM
The 4 horsemen...VSC, red triangle, skid, check engine jcat_350 ES350 (2007 - 2012) 7 11-16-12 11:25 AM
1996 es300 won't start. Trouble shooting with nothing yet, please help regorih ES300 and ES330 8 10-22-12 08:31 AM

All times are GMT -7. The time now is 10:21 PM.

Join ClubLexus
Advertising


Copyright © 2000-2008 Internet Brands, Inc. All Rights Reserved
Privacy Policy | Disclaimer | Terms of Use | JOBS


Get all contact info