code 41 & 47 limps @ 1900-2200 RPM's

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j_ls400

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Ok guys, I have a 94 ls400 with traction control giving error code 41 & 47. I have replaced the TPS 89452-33010 (driver side). I'm getting 5 volts to each TPS from the ECU. The car will give no problem if I accelerate very slowly. If I accelerate above normal then I encounter hesitation around 1900 thru 2200 RPM. The only way I can drive through this is by light acceleration. If I’m aggressive then it will not do anything. If I clear the codes then sometime the car will run just fine for a day or two. I have checked all vacuum lines visible and re-cut the ends to make sure there are no leaks. I followed the spec’s for testing the TPS and it looks like the old sensor is good. A local mechanic is leaning toward a new ecu but I disagree because I’m getting 5 volt to both of them. Please help, this has been going on for three weeks and I don’t want to give up and send it to the dealer. Very expensive for my budget.
 
If you have 5 volt refrence, you don't need an ECU. That is very unlikely that you need one. It isn't a Chevy.

41 means the ECU isn't recieving the TPS signal, it doesn't mean the TPS is bad. You likely have poor wiring somewhere.
 
I am having the same exact symptoms with a code 41 TPS. I know how I will attack the issue, but I just wanted to see if the ECU was your problem.
 
As far as I'm aware a code 41 goes to memory and can't be removed by disconnecting the battery .
I have just removed a code 41 that was the airbag light .
Go to www.lexls.com as their method works just fine .
As a hint remove the 3 phillips head screws in the bottom panel and pull it down and off [ there is a spring clip that locates around the steering stem as well ] , then remove the light and the diagnostic port by twisting them like a light bulb , this will enable you to have easy access to the port instead of having to bend down and then try to look up to see what you are doing !!I used two long wires and shorted them out on the door latch , got it first time !!
 
The TPS wirers are bad!

I just was told that the tps wiring is bad. The dealer said they show a open from both tps sensors. I can't afford a new harness and was needing advice on rewiring just the bad wires. Does any have info on the ecu pin out or advice on what I should do.

Jason
 
im having pretty much the same problem you described with it not moving if i push the gas too hard but drives fine if im light on the throttle. only code im getting is 47. my car doesnt have traction control but the ecu has been changed by someone in the past. it has writing on it from a junkyard. could this be a traction control ecu causing the problem? should i jump the vc to the vta2 as i read in another thread? i dont beleive the tps is bad though ill check it tonight with my meter.
 
ok, i checked the codes last night. had 41 and 47. i swapped in a spare tps i had and reset the ecu and drove it. no engine codes at all now but it still wont rev past 2k rpm if you free rev and if you push the gas too hard when driving it bucks. also, when its started from dead cold it idles perfect, once it hits opperating temps the idle jumps around and becomes rough. from all the threads ive read here and other forums it seems the ecu is the culprit. anyone know what exactly in the ecu goes bad? ive heard of people changing the caps and it runs better, but not perfect, but they didnt state if they used caps of the exact same values they removed or slightly different.
 

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u need to use caps of same uf and same voltage but same voltgae is hard to find sometimes so u can go higher voltage
repalcing caps prob works on 20% of ecus
ive done afew 1j ecus and no real success
anyway just goes to show that dealers are not smart thse days
they prefer to change the part rather than find the fault in the wiring and fix it
they want to replace the whole harness
they might just do this for warranty purposes aswell as they want to replace whol elot so u dont come back complaining bout another problem with the harness

anyway find the tps wires and run some new ones if u want a quick and dodgey fix
see if problems comes back
but if both tpses are playing up it is most prob the common earth or the common vc 5v

just remember solving problems like this for 99% of people will take maybe 3 or more weeks on and off or even months and most of the time its a fluke that u find it
intermintent probs are the worst to find and in the long run might be cheaper to
replace the enigne harness than spend 3 to 4 full days waiting fo rthe problem to occur
 
actually the engine codes for the tps signals are gone, so i dont see how it could be a wiring problem with the harness, though i built the engine harness for the 7m in my 84 from scratch for my megasquirt so repairing wiring wouldnt be hard.


the issue im having now is the white smoke at startup and exhaust smells like gas and bucks under hard acceleration. the funky idle after it warms up stays even with the maf unplugged, so it does appear to be a faulty ecu. instead of trying to look at every cap and then order them online and change them, i found a place that will refurbish the ecu for $100 and has a lifetime warranty. im repairing my cluster myself though. $200-$400 for that is crazy. already got the parts. should be able to pull it and fix it tonight as the gf has a work dinner to go to so i get some free time.
 
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not yet. sent the ecu to ate twice. second time under warranty. they havent fixed it yet. im trying to find another ecu so i can send mine back for a refund since they cant fix it. ive verified the tps and wiring are fine multiple times.
 
btw, i am still getting errors 41 and 47. my problem is that the vta wire has 1.7v on it when the tps plug is disconnected. this shouldnt have 1.7v on it. the other 3 wires check out fine. vc is 5v, e2 is gnd, and idl1 has 10v. ive got a thread in the wanted section for the ecu. need a ecu for a 93-94 ls400. i listed the 3 part numbers that will work in the thread.
 
Sorry to hear you are still having trouble. My ECM is also having trouble with its TPS circuit but in my case its the IDL only reading 1.4-2.0 volts. Maybe this part of the ECMs are starting to fail due to age and the fact they are 12volt circuit ?. I'm thinking going to a stand alone ECM. I haven't really got the money but this is my second factory ECM in two years and its killing me not to be able to drive my old beast of a car.
There are a lot of units to choose from now at good prices and even some maps that can be downloaded for some. Any how good luck and let us know when you get it sorted.

Andrew
 
your situation is why i didnt buy a used ecu to start with and decided to have it repaired. well ATE "Automotive Truck Electronics" isnt able to repair it and i DO NOT recommend anyone deal with them. ive spent $100 for the repair, which doesnt work, and $45 on shipping so far and they want me to spend another $15 to ship it back again so they can "try" to repair it again. or i can pay $15 to send it back in and they will only refund the $100 for the repair, not my losses on shipping. They are a horrible company to deal with. when i get another ecu i will post how it goes. ive checked and rechecked everything prolly 50 times, literally, and everything always points to the ecu.
 


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