jeastham

Anyone happen to have a HT lead for #3 cylinder (2nd in from front of right bank, when facing front of vehicle)

Plug came loose (thanks to DPO), and smashed the plug cap as a result of bouncing around the plug recess.

Ordinarily; I would buy a set of new leads; but I don't want to do that unless I can get the head helicoiled.

Name your price (if you have one)

Thanks

Well impressed with that! Paper clip too thin but bit of wire from old washing machine is made for the job.

Faults 13, RPM Signal #2 and 25, Air-fuel ratio lean malfunction.

Any ideas of what to change first?

And where are the disi caps? betting that they are shot along with rota arms.

Cheers

RPM signal comes from Ignitor #1 (with 5 wires going to it).

Try swapping the Ignitors round; worked for me.

Justin

Two things you can do with minimal tools....

[a] Find the diagnostic socket beneath the steering wheel. Mine (a 96 mk3) is white and circular. Short pins TE and E, which should be bottom-right, and two to the left of bottom-right. Turn ignition on, and count the amount of times the engine light on the console flashes (It will flash x times, pause, then flash y times for each fault code stored).

In my case, I had :

1 flash, pause, 4 flashes, longer pause, 1 flash, pause, 5 flashes, longer pause, 2 flashes, pause, 7 flashes, longest pause, before repeating the entire sequence. This signified error codes 14, 15 and 27.

Post your fault code(s)

Find the two igniter units, mounted near the O/S/F suspension turret. If the wiring will reach; move the wiring from the top igniter to the bottom, and vice-versa. If the wiring won't reach, you'll have to remove the igniter bracket, and physically swap the igniters in the bracket.

That's about all I can suggest without adequate tools and a multi-meter.

HTH

Justin

Engine runs !!

I swapped the ignitors round (they both have the same part #)

Ignitor #1 (now Ignitor #2) was failing to provide a clean RPM signal.

My Ignition wiring colours correspond to the 1996 wiring diagram. However; at the ECM (34 pin connector), my wiring is as follows :

12 : IGF1 : yellow-green

24 : IGT2 : yellow

25 : IGT1 : black-red

26 : IGF2 : yellow-black

In the two 1996 wiring diagrams; it shows IGT1 as black-red to pin 24, and IGT2 as yellow to pin 25.

It would appear that my car defies convention; especially as I have to refer to the 1994 repair manual to look up OBD1 fault-codes

Justin

Am I right in thinking that it is the crank sensor that governs the rev-counter ?

Something is causing the rev-counter needle to occasionally shoot up and down randomly.

Answering my own question.....it's #1 igniter which drives the rev-counter.

SO; tomorrow; I will check the earths for all the ignition components, and if they check out fine; I'm inclined to say #1 igniter is acting up.

Swapped out the Engine ECM and Crank Sensor; no difference :-(

So it's back to the multi-meter and schematics, in tomorrow's hot sun.

Getting hacked off with it now, if I'm honest.

Am I right in thinking that it is the crank sensor that governs the rev-counter ?

Something is causing the rev-counter needle to occasionally shoot up and down randomly.

Justin

Finally is the timing belt in good order? Is the timing correct? a worn belt may have jumped a few teeth on the sprockets.

Belt was done 3 or 4 years ago. Don't really do a lot of mileage.

Pretty sure the belt is fine; besides; it wouldn't have run fine at 3500rpm for 4 or 5 seconds.

My fault is one of degradation; started off as a momentary hesitation, and got steadily worse. Engine occasionally will fire and run for a brief period.

Will check the engine earth though

Thanks

Justin

Can somebody explain the difference between the 89661-50350 and the 89661-50351 ?

I'm guessing the latter is a slightly later and improved version of the former.

89661-50310 is what is currently on the car

89661-50350 is what is on its way

89661-50351 is what Lexus tell me should be on the car.

TIA

Justin

Bitten the bullet, and ordered up a Crank Sensor, and an ECM (89661-50350); £75 delivered.

If that doesn't fix it, then it's back to the multi-meter and schematics.

Justin

An update :

Cleared fault codes, and tried to run engine. Engine did actually run for about 5 seconds at 3-4000 revs, before dying. Which suggests to me that the engine is mechanically sound, and the problem lies elsewhere.

Checked fault codes again : 27 only. 14 (IGF-1) and 15 (IGF-2) have not returned.

Removed ECM, and took the lid off. I then re-connected E10 plug to ECM, and measured resistance (at the PCB) across pins :

5 and 6 (Crank sensor)

10 and 11 (#1 Cam sensor)

16 and 17 (#2 Cam sensor)

All were returning resistance in the 900 Ohm range (again using 2 multi-meters), which tells me that at least the wiring is good to all three sensors.

I don't believe my problem to be compression.

I don't believe my problem to be fuel; it fails to start on both LPG and petrol.

Can't believe that both ignition circuits (ignitors / coils / dizzys) would fail at the same time.

So I'm left thinking that it's either the Crank Position sensor acting up (I did experience the rev-counter needle bouncing around all over the place); or it's the ECM.

....or I'm missing something.

Really would welcome some advice; as I need to be mobile by Monday (Mother's Birthday).

TIA

Justin

P.S : Engine ECM is a "89661-50310"

I created a simple schematic, to help me troubleshoot my ignition problem(s). Might be of some use to others :

I have a 1994 LS400 wiring diagram pdf and the #1 camshaft position sensor wires are red and green , #2 are blue and yellow

Thanks. I have red & green wires going to a connector, and from that connector are red and yellow wires going to the #1 Cam sensor :-/

Justin

Could some kind soul confirm (or deny) that the wires that lead to the #1 Camshaft position sensor are red & yellow, and these red & yellow wires connect to red & green wires ?

TIA

Justin

Only had time to take measurements when cold.

1096 +/- 2 on one multi-meter

1102 +/- 1 on another multi-meter

....so within limits (835 to 1400 ohms)

Justin

Just bear in mind that when cold the CPS may read OK so even if the resistance readings are within spec when cold it may as you suggest be failing when warmed up which is not uncommon on other cars.

Keep us posted.

Good point.

I'll measure the resistance when I get home from work, and if it's within limits, I'll (try) and warm the engine up to temperature, or to the point where it's spluttering and misfiring, and take another reading.

I'm hoping it's the CPS, as that is an easy fix, and I've got an option on one for £25 inc delivery

Will report back

Justin

I am guessing that you have an LS400 post 1994 build year that is cranking but not firing?

It's a 96, but has OBD1. It does (or did) fire when cold, and it might even run for a mile or two.

The fact that you have no signal to both ignition amplifiers would suggest a common component.

Crank Position sensor was my initial thought. Got in the car last Tuesday, and the tacho needle was shooting about all over the place when cranking. Prior to that (from the Friday before), the engine would fire and run fine, apart from a periodic short hesitation, where the revs would drop, as though the engine was starved of fuel for a split second. It would only do this on LPG, not on petrol. Basically; it got progressively worse last week; to a point where it was seriously mis-firing on petrol by the Thursday. Bizarrely; the mis-firing was more pronounced when reversing. Whatever the problem is; it's something that has deteriorated, rather than just failed.

The other fault code probably has no relation to the above fault but may indicate the oxygen sensor is past its sell by date.

That was my conclusion; not a show-stopper.

Also bear in mind although useful in helping to diagnose problems, fault codes can sometimes be misleading and a little detective work and a multimeter are sometimes the better option.

Agreed. I paid the $15, and downloaded the engine section from the 94 Repair manual (plus a load of other PDFs).

Manual suggests that the ECM isn't receiving an ignition acknowledgement (IGF) from either Ignitor, and that the problem lies with the ECM, Ignitors, or the wiring inbetween. Can't believe that BOTH ignitors would act up. So I'm thinking Crank sensor, or less likely (hopefully) the ECM. Have the upper/lower resistance limits for the crank sensor, so will measure that tonight, and report back.

Thanks for the reply

Justin

Have managed to get the ECM to yield its fault codes :

14 - Ignition no. 1 signal

15 - Ignition no. 2 signal

27 - Sub-oxygen sensor signal (on left bank)

Anyone able to suggest what I should be swapping out for 14 and 15 ?

TIA

Justin

Thanks for the reply.

So I have an OBD1 connector - explains why I coudn't find an OBD2 connector that looked like mine. Strange though, as I thought being a 96 model; it should be OBD2.

Oh well; saves shelling out for a fault-code reader

Wasn't aware there was a diag interface in the cabin. Where would I find that; behind/under/near the glove box ?

Thanks again

Justin

I'm LED to believe that my LS400 should have an OBD2 diagnostic interface, utilising the CAN protocol (either 250 or 500 Kbit)

The diagnostic interface is shown below. Can anyone identify what the connector is; I need to know so I can order up a fault-code reader (suspect my cranshaft-position-sensor has expired)

Also; I'm not sure if it's supposed to have the contacts covered in that gunk; can only assume it's corrosion prevention.

TIA

Justin

Searched the forum, and not come across anything similar, so here goes......

My temperature guage requires an exorcism. It will steadily climb up, almost to the red, and then drop like a stone to the mid-point on the guage.

If I'm stationary in traffic, and the needle starts to climb up, then turning the ignition on and off sets the needle close to the midpoint.

The car is LPG converted, so there is a coolant hose running over the top of the engine (to supply coolant to/from the Vaporiser, to stop it icing up).

I'm thinking :

1) Air-lock somewhere in the coolant system, but then surely any trapped air would get pumped around with the water, and end up in the expansion tank ?

2) Dodgy coolant temperature sender - Any ideas as to where it lives, and how much of a 2nd mortgage I need to buy one from Lexus ?

3) Dodgy temperature guage; never had this happen before.

I welcome any advice. I might pop down to Lexus tomorrow, and enquire as to the cost of a sender and guage

TIA

Justin

Hi,

Got a little project in mind, so I'm after the plastic unit that houses the centre vents, clock, and out-side temperature display.

Clock and temp display aren't really required, but having the unit complete with the vents would save some hassle. I believe

this is how they are supplied by Lexus ( EPC # 55660)

Anyone got a series 3 they're scrapping (or have scrapped) ?

Anyone seen a series 3 in their local scrappies ?

TIA

Justin

Justin, my bearded friend!

According to the EPC, the part number for the 1UZ-FE intake manifold is 17111-50020, and fits all LS400s from December 1989 to July 1997.

Looks like you're in luck!

Top banana !!

Cheers matey

Justin

Hi all,

Anyone able to tell me whether the inlet manifold on the series-2 LS400 is the same as that on the series-3 ?

If not, how could I find out ?

No point asking Lexus, they won't tell me anything without a chassis number

TIA

Justin

Typical, why can we never time failures to parts at the right price?

Only recently finished on ebay at 99p!

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...p;rd=1&rd=1

My PAS hose is different to the one that was on eBay

Just tried to upload a graphic of it, but it won't let me.

Try these no's for Lexus breakers,i just got a h/light from the top one.

01327 310511

08450 664422

0774 8701572

:)

Hi,

Do you (or anyone) have the names for the numbers above ?

Trying to avoid phoning places I've already called