Left bank down, no spark, running on 6 cylinder

Check this out :

 

I checked the phase sensors here, plus swapped them over.

 

Then Mike checked them and checked the timing against them, said they were perfect!

This is the kind of stuff that should scare the crap out of potential buyers. I'm surprised Audi and all that great "German quality" are having no better luck than the Italians, but really not surprised at all. Always thought it was way over stated.

 

Anyway, this is the Achilles heel of low volume exotics. My guess is there will be allot of our cars sitting around in the future with these types of problems, and owners unwilling to pay for repair....Or attempted repair.

 

Sorry to go off, but having been victimized by this and seeing others have to deal with it is pretty discouraging.

 

I hope you both get lucky soon.

 

You could be right! With parts already being discontinued for certain items, and these types of issues arise, it certainly makes you wonder.

 

As a Joke [with a possible hint of being serious] Mike mentioned to me that maybe it would be just simpler to pull the engine out and drop it into another car, this way it would cancel out if it's the OEM wiring loom!!

 

The wiring on these is a very weak spot. I replaced left and right harnesses, but we'll see when I get the TB's back...but there is still the harness that goes through the firewall into the lie..... they kink it so bad where it goes down into the frame...... all it takes on these cars is one bad connection, one broken wire and your finished

Had an ignition module go out once. Ran real bad. 1 each located on top of coils

Had an ignition module go out once. Ran real bad. 1 each located on top of coils

 

Those have been checked and swapped over too.

Those have been checked and swapped over too.

 

Im betting dollars to donuts that you have valve timing issues. Have you checked compression on the left and right banks?

Im betting dollars to donuts that you have valve timing issues. Have you checked compression on the left and right banks?

 

Yip, compression checked on all 12 by myself, and also by Mike Pullen, no issues found. I believe Mike already checked the timing and it was spot on.

Yip, compression checked on all 12 by myself, and also by Mike Pullen, no issues found. I believe Mike already checked the timing and it was spot on.

 

Ok,

 

Let me recap and correct where needed.

 

runs on 6 cyl only, switch ECU's still runs on the same 6 cyl only?

You swaped dist cap & rotor, no change?

You swaped ign module l-r & r-l, no change?

Comp & Valve timing perfect?

Both fuel pumps working?

Alarm system arms and disarms?

 

 

Ok,

 

Let me recap and correct where needed.

 

runs on 6 cyl only, switch ECU's still runs on the same 6 cyl only?

You swaped dist cap & rotor, no change?

You swaped ign module l-r & r-l, no change?

Comp & Valve timing perfect?

Both fuel pumps working?

Alarm system arms and disarms?

 

The car runs on all 12, it's just not running correctly on 7-12 bank.

 

Recap:

 

So just to recap,

 

The car was running 100% before, and this is something I keep telling myself, as it hasn't gone anywhere since it was running 100%. So I keep thinking it must be something simple.

 

It was parked up and the following day I started the water pump replacement, once all the bits arrived, I put it back together, but the car didn't run the same. It first only ran on 1-6 cylinders, after discovering the fault was those couple of small broken wires I mentioned, at the coolant sensor and phase sensor, they got repaired and it fired up on all 12. However it has not ran correctly.

 

I also found a broken wire on the TPS sensor, but I also replaced that with a new pin too.

 

To summaries, the car runs lumpy/hunting the revs, odd misfire when running on all 12. If I disconnect bank 7-12, it runs perfect on 1-6, if I try to run on just 7-12, it runs, but poorly.

 

Fuel smell is coming from left exhaust, bank 7-12.

 

The checks/replacements so far.

 

Coils were checked and tested

Ignition modules checked and tested

New HT leads

New spark plugs

New coolant sensors

New thermostat

New water pump

New 02 sensors

New ignition rotor

Distributor cap is the old OEM one, but I tested with a NEW one and no change

Phase sensors volts tested - both read the same

Fuel regulators swapped over - no change

Disconnected fuel lines after the fuel filters - fuel does flow

Swapped the fuel line from left to right banks to see if it makes a difference - no change

LIE computers have been swapped over to check if the fault follows, it never has.

Listened to the Injectors and all sound like they are clicking nicely

Compression test - all show around same results

 

 

Further update

 

I think that's me completely beat lol, apart from new OEM leads coming, which I doubt will help, I can't really investigate much further or find any faults.

 

I've

 

Fitted new leads [cheaper versions] but still work, swapped those leads from left to right bank to be sure, no change

New spark plug fitted, swapped them from left to right too, no change

New 02 sensors, checked those on the meter and both read around the same

New coolant sensors - also tested by swapping banks over, no change

Map sensors checked and swapped, no change

New rotor installed - even swapped that new one for another new one to be sure, no change

New cap installed - no change

Coils checked and swapped over, no change

Ignition modules checked and swapped, no change

Spark test done, all ok

LIE computers tested by swapping over - no change

Fuel regulators swapped over - no change

Complete Fuel injectors and rails swapped over - no change

Fuel lines after the fuel filters disconnected, fuel seems to flows ok

Swapped those fuel lines over to cancel out it was fuel pressure, no change

Cylinder compression test, no major dips

Vacuum hoses all checked

Phase sensors tested and swapped, no change

Checked the hose from the brake booster to the manifold, no leaks there

Manifold air temp sensors checked and swapped, no change

Wiring checked at all the above and at the connectors, all ok

Got the bulb replaced on the check light, check light now working, but not showing any faults

 

Only other thing I can think off, is still maybe fuel pressure some how? Is it possible it could be fuel pressure even though I swapped the 2 fuels lines around at where they go into the rails?

 

I also find it strange the 02 sensors are reading pretty much the same, cycles quickly from around 140 to 900 on the meter.

 

From the above updates, there were a few more checks and items replaced for new, then early this year, I sent the car to Mike Pullen, very well know Lambo experts in the UK/Europe, it's been there ever since as he can't figure it out either.

EGR Temp probes, did you unscrew from the cats or never touched?

KAVLYCO Sensors (M.A.P.) did you repair the wiring?

EGR Temp probes, did you unscrew from the cats or never touched?

KAVLYCO Sensors (M.A.P.) did you repair the wiring?

 

Probes on my car were disconnected years ago as the cats were hollowed out.

 

The MAP sensors were fine and wiring all good.

 

 

How much would a new wiring harness for that bank cost on a Diablo?

How much would a new wiring harness for that bank cost on a Diablo?

 

Some are few hundred dollars, some are over 3000 dollars, and some are NLA I think.

I bought both sides engine harness from Glenn at AMH for the Murci for a real good price...all OEM brand new... On the Murci there is a left and right harness, then a mid harness that goes through the firewall into the engine bay and connects to the ECU's. Did you check your ground straps? also the bolts to see if they were not oxidized?

I bought both sides engine harness from Glenn at AMH for the Murci for a real good price...all OEM brand new... On the Murci there is a left and right harness, then a mid harness that goes through the firewall into the engine bay and connects to the ECU's. Did you check your ground straps? also the bolts to see if they were not oxidized?

 

I checked all the ground straps, and replaced one at the rear as it was completely missing, but it looked like it was always missing, and didn't affect the running of the car.

Hi Sudesh,

 

I feel your pain, being without your car for so long. I noticed in one of your other write ups that you replaced the connectors for the phase sensors and temp sensors. Is there any way that the wires were put into the connector reversed? It would be easy to do. When you say that you checked the vacuum hoses, did you check for vacuum leaks or confirm that they were all connected according to the vacuum diagram? At work years ago, one of the mechanics had two vacuum hoses switched by mistake and the van failed our Government smog test. 3 other mechanics replaced lots of sensors, etc but failed to figure it out. The final guy who was given the job, got out the manual and started comparing factory pics and drawings and noticed the error. On my car I found that someone previous to my ownership put on new vacuum hoses to the fuel regulators, but had the 1-6 regulator plumbed to the 7-12 throttle body and vise-versa. One of our lead mechanics told me a story about a time they had a piece of equipment that had a hose de-laminate inside, the little flap would flip down under full pressure and block the hose. Unlikely, I know, but at this point anything is likely.

 

Best of luck, hope you get it figured out soon.

Hi Sudesh,

 

I feel your pain, being without your car for so long. I noticed in one of your other write ups that you replaced the connectors for the phase sensors and temp sensors. Is there any way that the wires were put into the connector reversed? It would be easy to do. When you say that you checked the vacuum hoses, did you check for vacuum leaks or confirm that they were all connected according to the vacuum diagram? At work years ago, one of the mechanics had two vacuum hoses switched by mistake and the van failed our Government smog test. 3 other mechanics replaced lots of sensors, etc but failed to figure it out. The final guy who was given the job, got out the manual and started comparing factory pics and drawings and noticed the error. On my car I found that someone previous to my ownership put on new vacuum hoses to the fuel regulators, but had the 1-6 regulator plumbed to the 7-12 throttle body and vise-versa. One of our lead mechanics told me a story about a time they had a piece of equipment that had a hose de-laminate inside, the little flap would flip down under full pressure and block the hose. Unlikely, I know, but at this point anything is likely.

 

Best of luck, hope you get it figured out soon.

 

Hi Steve,

 

How are getting on with yours?

 

I checked the hoses for leaks and also if they were fitted correctly, couldn't find a single problem there, I even used a smoke machine to check for leaks correctly.

 

On the connectors you mentioned, The wires can't really be put in incorrectly, if they were, it pretty much wouldn't run at all, especially where the phase sensors are concerned, but yes understand what you mean, and when I did the repair, I marked the wires with a dab of paint to show which goes into which slot, learned that years ago when I was building a new wiring loom for a car.

 

Another stab in dark. Did you do the computer relearn procedure ?

Another stab in dark. Did you do the computer relearn procedure ?

 

Yip! lol

 

 

Did you check the gap on the phase sensors? Should be 0.7 - 1.0mm

 

Did you check the fuel pressure and fuel volume from both pumps?

 

Does Mike have the "Lamborghini console" p.n. 9250157 ? (page B132 - 26) this would allow him to select the data from 7-12 bank

 

In section B132 of the Service manual page 51 - page 64 there are diagnosis procedures, does Mike have "Lamborghini test box" (mentioned on page 51) to complete the 42 tests listed?

Did you check the gap on the phase sensors? Should be 0.7 - 1.0mm

 

Did you check the fuel pressure and fuel volume from both pumps?

 

Does Mike have the "Lamborghini console" p.n. 9250157 ? (page B132 - 26) this would allow him to select the data from 7-12 bank

 

In section B132 of the Service manual page 51 - page 64 there are diagnosis procedures, does Mike have "Lamborghini test box" (mentioned on page 51) to complete the 42 tests listed?

 

Not sure on what diagnostic equipment he has? But I know he has checked the fuel flow and said it was fine, pumps running ok too.

 

He has checked the phase sensor gap, but remember I also swapped them over to see if there was any change, there wasn't.

 

Spoke to him yesterday, and he was going to swap the distributor cap with another, but I told him the one on my car is a NEW OEM one just fitted, plus I still have the old OEM one in the trunk, plus one of those crap Jaguar type caps, the car has run exactly the same on all 3 caps, but hes welcome to try any of them again.

 

After this he's talking about doing some dual marking on the fly wheel and checking the timing again.

I have same problem.....everything's are ok.....all I can guess the problem is between battery to ecu not ecu to distributor . Cause there is no electric power go throw ecu when I turn on the key.

Yours sounds like a simpler fix. There is power going to both my ECUs ok, that's already been tested a few times,

 

If there is no power at your ECU, you can run a volt meter on there to check.

Hi "Sudesh",

 

You would not belive... I have nearly similar issue!

My car give MAP sensor warning light, shange from side to side, engine warning light followed. Ordered nearly similar (Lancia/Cosworth/made in china part) and found out today that I do not have spark to all cylinders.

I do have similar issue of fuel smell and runing only with partial cylindersout of the play, but after I get cleaned distributor cap instaled I'll get back to this.

 

Does your car have spark in all cylinders? All the time?

Have try to change MAP sensor to compleatly new ones?

 

Can it be; MAP sensor needs to give wrong reading more then 16s, so LIE would give warning light. If MAP sensor works only partially and would not trigger warning?