rapike63

Need help...my ls400wont start.....I drove it to work last week and when i got in it to leave it would turn over but it wouldnt start.I left it there and came back the next day and tried to start it that mornin...same thing...after work I tried it again...it started....I drove it home...it ran kinda rough. The next day ...Sunday I started it and drove it down the road ...still running rough....Stop at red light it went dead,wouldnt start back.Had it towed home...ran codes on it and it says TPS is bad.Will the the TPS make it not start or start and then run and then die,and wich one is it there are 2 of them

deanshark

I don't ever recall one not starting b/c of the TPS but I could be wrong. I have heard a couple people who got code 41 for the TPS and it turned out thier ECU was bad. The main TPS is the one towards the center of the engine, the one closer to the fender side is the sub-TPS which works with the traction control. You can check the TPS with an Ohm meter to see if it's in spec. This shows how; https://www.clublexus.com/forums/sc-...on-issues.html

rapike63

thanks will do that

rapike63

Ok..replaced the TPS now Im getting a p1600 code ecm batt malfunction...you think the ecm is bad?

deanshark

Wow my mistake , I didn't realize it was a 95. So it wouldn't have had a code 41 for the TPS, that's for an OBD1. Anyway, the code p1600 does point to the ECM. Check to make sure all the wires are plugged in on the back of the ECM. If it is bad you can probably find a used one at the junkyard for a hell of a lot cheaper then a new one from the dealer.

rapike63

If the ecm is bad...wich one is it......the one on the left says engine control on it ....is that the ecm.....or the one on the right...I suspected the ecm was going bad....because it would act strange....Run rough one day then do just fine most other days...like not change gears or gear down for no reason...or run like it was misfiring...Im not a mechanic ...so I just figure it was just old ....it does have 230,000 miles on it...Any help would be appreciated

emarknot

ec...ecm....engine control module..

deanshark

It's the one that has lots, and lots..., and lots of wires.

Ls4speed

Hmmm I'm having a similar problem with my 91 ls400 except mine overheated on a less than 8mi dive and wouldn't restart the next day it started up but felt sluggish now its just wont I've been told everything from stater to coils is there any one who has had this problem on a 91 142k mi no other problems ever

KDAWG97M3

I may have an extra ecu

emarknot

if the one on the right has ec, or ecm, or...engine control..........that would be the one.
its clearly not the one that says cruise control

deanshark

It's the one on the left not the right.
Here's one on Ebay but I'm sure you can get one from a junkyard cheaper. If the ECM is the actual problem. http://cgi.ebay.com/ebaymotors/COMPU...item483e0a477d
emarknot; your original quote said it had 1 pigtail, which you can clearly see it has 5 or 6.

emarknot

I could not clearly see.
I didnt notice the one on the left.
that why I said ..."if" the on the right.

thats why I changed my original post.

I just barely woke up.

and again, I didnt notice the buried to right.
but thank-you