LANcr3w

Ive posted before on many troubles ive faced to getting this car i bought running.
Its a 1994 LS400 only 140,000 miles
Timing belt was replaced ( in time)
distrubutor caps and rotors
spark plugs
plug wires
compression good
fuel pressure good
injector O-rings
and ECU

Im still believing that the ECU is whats causing my current problem
The first rebuilt ECU worked perfect then it rain leaked through my sunroof and ruined the ECU
so i had it rebuilt again. This one worked perfect as well, but as i was driving it lost all power
now it feels like a 3 cylinder, sounds raspy and rough. RPMS are very slow when revving the car.
It also smells very rich of fuel almost if it was pouring onto the ground but there are 0 leaks.

Still believe its the ECU? or anyone know if thats a different problem?

LScowboyLS

well ECU is the most likely, but it's not the only thing that can make an LS400 run bad or rich!

If you want to pull the ECU and photograph the capacitors inside at a good enough resolution to see the manufacturer's markings and read the codes on them, then I can tell you whether they are the correct type and whether they are installed correctly!

cobalt91

Witch bank is not fireing?

LANcr3w

When i scan the codes on the car i get code 13 or 31. Which 31 is AFM signal....this seems the most plausible cause of why it runs the way it does.
But i scanned again paying close attention it flashes once first then 3. So i get 13. RPM signal.
What does this RPM signal mean? and could it cause my car to run bad? If not 31 looks like a more probable cause on why my car has no power. Because if its neither one of those then i know for sure its my ECU again.

LScowboyLS

code 13 is often something you would never guess - timing belt jumped by just one tooth on only one cam pulley - I would check that right now!

and that WOULD cause these issues, just as ECU caps could as well as a bad crank or cam position sensor, but jumped time is by far most likely

if timing is indeed slipped, I would replace belt with genuine Bando or Mitsuboshi (Toyota part) even though your current belt is new (it is ruined now) and replace hydraulic tensioner with genuine NTN or Toyota and make sure every thing is perfectly oil free inside timing belt area including all pulleys - rotate crank several times once you are done and tensioner pin is pulled, to double check (always clockwise)

Timing belt replacement and alignment procedure from factory service manual

LANcr3w

Ill try to get some pics up on the ECU for you lscowboyls. Im thinking if its actually spitting out codes the ECU is working and i mightve over looked this check engine light.

But im hoping now that it is just the timing jumped, im tired of sending this ECU off back and forth lol.
Ill probably tear into the car today as well.

LANcr3w

Could having a loose hydraulic tensioner be a reason the belt slipped?
About how much does the hydraulic tensioner run?

LScowboyLS

Yes!


new Toyota part number is 13540-50030 about $47 online but here is one on ebay for $28 w/ free shippin

LScowboyLS

best deal I have seen on a genuine LS400 OEM timing belt

LANcr3w

Thanks i appreciate it. Im going to start on it tonight and ill let ya know what i see.
And that should be all i need is the belt and hydraulic tensioner? just noticed a lot of kits come
with a water pump as well.

LScowboyLS

well yes, I was telling you the quick and dirty fix - but if you want to go all out and do it right, the Toyota/Aisin TKT-030 kit has everything you need - bearings, idlers, tensioner, drive belt, timing belt, water pump and they are all original Toyota parts and the whole kit is like $190 on ebay

LANcr3w

Alright so im slightly disappointed in my findings.






So It looks to be perfectly timed to me. Unless im doing it wrong... But ive also had a Toyota technician take a look at it and he said that that means its in time.

LScowboyLS

I can't tell much from the pics, but you have to make sure when crank is at 0 that BOTH cam pulleys line up with BOTH backing plates - then rotate engine twice and see if they still both do - the belt itself also should be identified as far as you need to report it's part number to us here, there is such thing as the incorrect belt

the actual markings on the belt are not critical they are there just to help you during installation.

did you reread the timing belt installation tips in the service manual on what they say on alignment?

LANcr3w

it is slightly hard to see in the pictures but the small notches on the cam gears both need to line
up with the lines and thats what im trying to show. The notches on the gears are dead even with the lines on the back when on 0 at the crank.

Is that not the correct way to show its in time?

LANcr3w

I actually just checked AllData that i have access to at work and it shows the notches being
lined up. I know that mine seem to look dead on so i believe the timing is still good.