Ignition Drop Outs

Hello,

 

I am new to the board and first In want to introduce myself.

I`m living in Heidelberg / Germany, 47 years (young) and after a 308 GTSi QV and a Testarossa I was ready to buy my first Lambo. A 1994 Diablo VT in deep black.

I am very happy with my new toy and do not regret the change to the dark side;)

But, from the first day on I have a problem that even my top mechanic master can not solve.

May I ask you for help? Any advice would be highly appreciated.

 

Ignition Drop Outs!

 

It started with drop outs at around 5.500 rpm/s (each gear)

Can`t go over 5.500 rpm/s it drop down under 5.000.

Till 5.500 the engine is running perfect without any doubts.

When the engine is COLD, it does not happen but just after a few miles and

a little warm up the problem shows of.

Check Engine L is flashing

Drop outs

Check engine L & R is flashing.

After a while and under 5.000 the Check Engine flash is gone.

 

We checked the error indicator with the key check.

Check Engine flashes 6 times – on the list error number: 6

“Engine speed & timing sensor signal wrong sequence”

 

What we have already done and changed:

- Both time & speed sensors, new

- Both ignition coils, new

- 12 new plugs

- the complete ignition cables (plug leads?), new

- checked all fuses

- both air temp. sensors changed, new

- OT Geber changed, new (upper transmitter between engine and gear box very difficult action)

 

After each repair we did a test drive. Car run up to 7.500rpm`s without a problem but after 5 miles same problem again. (NO, I usual never run my car on high rpm`s when its cold – just to proof the situation).

Now, the problem is getting more and more curious. Ignition drop outs started at 5.000rpm`s and a few days later at 4.400rpm`s.

Is my Diablo dying slowy……?

 

Andy ideas, thoughts, help?

 

Thanks in advance

 

Yours

Wolfgang

 

P.S. sorry for my poor english, its my second language and hard to describe technical things in english.

Check your coolant temp sensors. This happened to me, and after several attempted fixes, this was the true fix.

I would put money on this fix.

If this works, send me a struddle.

Check your coolant temp sensors. This happened to me, and after several attempted fixes, this was the true fix.

I would put money on this fix.

If this works, send me a struddle.

 

Thanks a lot for your very quick reply.

I am not the mechanic thats why I have to ask you:

Are this the 2 sensors mounted on top of the engine between

the 2 cylinder heads (blue pins if I remember right and easy to change cause

they are on top of and between the heads)?

If yes, we have already changed them and still the same problem.

If not, I ll tell my mechanic asap to replace them.

 

Wolfgang

 

These are located in the thermostat housing.

These are located in the thermostat housing.

Thank you very much for the great pic & location description.

Yes, this are the 2 sensors we have already replaced and sadly not the problem solved.

 

Are your ECUs functioning properly.

What do the tailpipes look like. Is one side black and the other not?

 

Are your ECUs functioning properly.

What do the tailpipes look like. Is one side black and the other not?

About the ECU I don`t know if he has checked it or how to proof?

About the tailpipes: Yes indeed there is a huge difference between the left and right double pipes.

The left side is white and the right side is dark red.

The car is fitted with the original cats but with a tubi style - so no way to see if the right

tailpipes are from the right engine side -who knows whats going on inside the tubi?

But anyway, what does it means ?

 

I had same code as yours.

Unfourtunatly when check engine light went on I didn't try to

rev hi. Don't know if ignition would drop out.

The problem was a phase sensor. There are 2 of them.

The wires appeared to be pulling out of one. They are located next to distributor.

On the other cam

 

I had same code as yours.

Unfourtunatly when check engine light went on I didn't try to

rev hi. Don't know if ignition would drop out.

The problem was a phase sensor. There are 2 of them.

The wires appeared to be pulling out of one. They are located next to distributor.

On the other cam

Thank you very much.

This are the tim & speed sensors?!

Yes, we have already changed them. They are close/left from the distributor....still the same problem.

 

Hope this helps,

One more speed, time sensor on top of bell housing ( flywheel )

May need to check all connectors for bent pins?

 

 

Hope this helps,

One more speed, time sensor on top of bell housing ( flywheel )

May need to check all connectors for bent pins?

Once again, thank you very much.

About the sensor on top of the bell house (flywheel):

---sorry, its very difficult for me to translate technical stuff---

We have changed one more sensor and I want to know if we are talking about the same.

We call it OT Geber in german - something like "upper transmitter ". Its located ad the end of the engine, close

to the fire wall and than down under ........ very hard to change. Screws are difficult to open - we did it from under the car

with a special tool. The sensor looks (in my amateur eyes) like the other two sensors from time & speed

But the flywheel is very close to the sensor I remember.

 

Thanks in advance.

 

If the the OT sensor is bad the car will not start at all.

you should try to swap the ecus located behind the passinger seat under the CD changer box, it a simple jop, just swap the connecters.

check if the code went to the other side or not.

 

Hope this helps.

Wow, I'm sure youv'e checked most of these

Just throwing things out there that could keep a motor from reving

 

Cloged cats

fuel filters, pumps

bad ground, check the rusty ones on the exhaust too.

throttle linkage ( when warm is binding or secondaries not opening. ) maybe when cold is getting air

from cold start bypass valves.

 

Please keep us posted

 

 

 

 

 

@Hazim,

you are right about the OT sensor - we have done a useless job.

About the ECU`s: Great new idea to swap the connecters and to see if the code went to the other side.

My idea was to replace both ECU`s for a test, hope my garage has 2 new in stock just for test drive.

They are insane expensive.

 

@13mm,

throttle linkage - yes, another great idea and input.

 

I will happy forward all ideas and advices to my garage master. Please keep on!

Each thought is highly appreciated and I am very thankful for all your help gents.

 

I`ll have a date in my garage for next week. Hopefully we can fix the beast.

 

Wolfgang

@Hazim,

you are right about the OT sensor - we have done a useless job.

About the ECU`s: Great new idea to swap the connecters and to see if the code went to the other side.

My idea was to replace both ECU`s for a test, hope my garage has 2 new in stock just for test drive.

They are insane expensive.

 

@13mm,

throttle linkage - yes, another great idea and input.

 

I will happy forward all ideas and advices to my garage master. Please keep on!

Each thought is highly appreciated and I am very thankful for all your help gents.

 

I`ll have a date in my garage for next week. Hopefully we can fix the beast.

 

Wolfgang

 

 

We have seen a similar problem twice this year. seemed to be a temp/rmp/load related problem that was intermitant.

Did not happen when the car was cold.

After extensive diagnostic, sensor checks, power and ground checks, we swaped ecu's.

Problem did change sides. We replaced the bad ecu, problem solved.

 

george

 

Hello George,

 

great to hear I am not a the only one with this problem.

Yes, we will swap and proof the ECU`s and if necessary install 2 new ECU`s.

 

What makes me still wonder is the fact that the drop outs started 1 months ago at 5.500, 2 weeks later

already at 5.000 and another 2 weeks later now at 4.400rpm/s (driven within this 4 weeks 2.000miles) ?!

Now I dont drive it any more till its fixed.

 

Are you still getting a code 6? after all the work that has been done. Code 6 can have somewhat of a double meaning. It can mean one or both of the sensors are going bad. But it can also mean what the code says, they are out of phase. due to things like chain strech. The ecm will see that the speed sensor on the flywheel is not matching the signal from the phase sensor and set that code. Its easy to check the timing on the sensors. Bring the engine to TDC #1 or PM1 on the flywheel. Remove the cover on the phase sensors. At tdc the pointer wheel should be exactly between the 2 sensors.

Hello Mike,

 

thanks a lot for your adice.

My mechanic has matched / done it the same way you described it - I was close beside and helped him.

He changed both time & speed sensors and the speed sensor on the fly wheel and adjusted it exactly like you describe it.

......still the same problem.

He will pick up my car today on a flat bed to bring it back to his garage. Hopefully he can solve the problem now with all the help I have got here.

 

Please keep on with your brilliant ideas gents.

Each input could help us.

 

Thanks

 

Wolfgang

Wolfgang, any news ?

Wolfgang, any news ?

Thank you very much for asking.

No, but hopefully today.

Yesterday he came with the trailor to pick up my Diablo.

Today he will work on it and hopefully solve the problem.

I handed him a list with all your ideas and input - what else it could be.

I cross my fingers cause I realy would love to drive my beast again asap.

Weather is beautiful in Germany and we have a lots of drive outs & Lambo meetings during the next weeks.

 

I`ll keep you updated!

 

Thanks all

 

Wolfgang

Thank you very much for asking.

No, but hopefully today.

Yesterday he came with the trailor to pick up my Diablo.

Today he will work on it and hopefully solve the problem.

I handed him a list with all your ideas and input - what else it could be.

I cross my fingers cause I realy would love to drive my beast again asap.

Weather is beautiful in Germany and we have a lots of drive outs & Lambo meetings during the next weeks.

 

I`ll keep you updated!

 

Thanks all

 

Wolfgang

I would be very interested as to what he finds out.

I would be very interested as to what he finds out.

 

update:

Good news - they found the fault

Bad news - its getting serious expensive

 

(hard to translate for me)

Its the a "balance-bearing" from the "crankshaft".

 

Here is a link to the whole crankshaft:

http://www.eurospares.co.uk/partTable.asp?...;B=38607&S=

 

This bearing has x20 times more "bearing play" as usual or standart.

 

So, its a 170 hours job - engine out, complete strip down to the crankshaft, hand made new bearing(s),

and maybe the one or other part to fix while the engine is out.......

 

Sometimes it must be more than love & passion to keep this "tractor" alive.

 

Wolfgang

anytime it goes internal, its going to be expensive.

What causes that particular bearing to wear? Was there something else wrong that caused the play like that?

anytime it goes internal, its going to be expensive.

What causes that particular bearing to wear? Was there something else wrong that caused the play like that?

I don`t know???

Just count the 170 hours of work X $ without parts

 

Sorry to hear it's a major.

How many KMs does your car have ?

Type oil, changed often ?

Am I understanding the main bearings are worn ?