boxsey911

Which distributor cap and coil did he leave connected when the car idled OK? If it was running OK with only the cap nearest the engine fan connected, it could mean that the distributor belt is broken. So ask him to check if the belt is OK.

m3vs911

He said he has done it already but it is just the 2nd plug from the ECU (he said) to the coil (no matter to which coil) is causing problem. Moreover, he has replaced the pick up sensors which I have not been informed... although they are 150 pound but I jst don't like this kind of dealing method.

I am taking the car out the garage later and planning to continue the job with another specialist now..

m3vs911

he is now saying that is coils and distributors are still ok to run for now.
is it just the ONE PLUG connecting to the coils from the ecu.

I am lost!

boxsey911

The 964 has a pair of coils. One coil supplies the HT to one distributor cap and one coil to the other cap. The primary distributor is nearest the engine fan and is driven by the engine. The secondary distributor is driven by the primary via a belt. The belt is inside the twin distributor mechanism and you need to remove the caps to see it. If the belt breaks, the secondary distributor is no longer being driven. At best it is then not supplying spark to the second set of six plugs. At worst, the rotor arm is stuck on one the HT contacts inside the cap and supplying a spark to one plug all of the time. Which could be very damaging.

I should say that I don't know if you have a broken belt or not especially because it would be a big coincidence that it broke when you changed the chip (when all your problems started). However, I suggested the belt be checked after your garage told you the car is OK on one coil only. Your garage should know all this if he is a 964 specialist. I'm pleased to hear you are going to take it somewhere else!

m3vs911

Yes. just had the car back in hand, running smoothly with one coil and I can see the other one has been disconnected.

I will post pictures to show you and everyone here.

at least engine runs fine now but with lack of power that i can feel.

thanks again x

m3vs911

this is what the mechanic done and in the picture there is a 5pin square plug is disconnected from the module from the left hand side, next to the coil.

he mentioned that if he plugs that back in, it ignition timing will be messed up.


the reason why he ordered the pick up sensor is because he found fault code from the diag device, so i think its fair for him to replace it without notifying me. however, it does not fix the problem at the end.

Cheeksyboy

You may not like me for saying this, but for what it costs, take it to somewhere like 9Meister, Unit 11, or Autofarm....someone who really knows aircooled.

It may seem like it costs more, but you'll spend far more chasing the issue with someone else.

I'd suggest you call any of these places first to discuss your issue and decide youself who you trust can do the diagnistic and wrk for what they quote.

I'd go to 9M, but that's just me....

I would not think it best to run the car for long, or especially at high revs, on only 1 coil.

m3vs911

to me it is very rude to replace parts without any prior notification. however as what he said to me today it's appearing on his hammer.

I'm bringing my car zentrum on Monday. they have already confirmed that they got a spare DME for 964.

CBR786

have you not got a spare car to run about in? I am coming to notts on SAT or Sun depending on if I can get hold of my friend. I need to pick up a 996 gear box off him. I can bring my PST2 (hammer) tester and plug it in see what codes are being thrown up if you like? if that ignition module has gone they are cheap enough used on ebay or maybe pattern from euro car parts or GSF etc. I would also double check your distributor belt it is an easy check. Along with caps and rotor arms

m3vs911

hi mate, I don't have a spare car to run. I've checked my coils this morning, what I did is either use one coil to start the car each time and the car is fine. stalling issue only happens when the car is running with 2 coils together ...

m3vs911

Hi mates,

New updates from another specialist today, very quick inspection 2 hours later after dropping in.
he claimed that my stalling problem is completely not due to the ECU,
it is down to the cracked sparking leads , I want share this information with you since I have tried to run the car with each coils separately, no problem until i connected both coils together.

Would this be true?

He suggests that if I want to keep the car, I need to replace a full set of leads, distributor caps, and arms.

advice needed!

jotaking

I presume that there are signs of damage on the HT Leads??

If this is the case, it shouldn't have taken 2 hours to spot and wouldn't the last Mech seen this?? (just my opinion)

I would ask to see damage and the internals on the Dis caps to verify damage/poor performance.

I haven't had this problem... although my HT leads had been taped up and had signs of wear they worked okay. I replaced my leads for aesthetic reasons with a virtually new set from Douglas Valley Salvage(Wigan). Saved a fortune.

Hope this helps

Good Luck!!

CBR786

COPIED FROM ANOTHER SITE BUT THIS MIGHT HELP

Instructions


Things you need
Multimeter
Tachometer
Spray bottle
Water
Masking tape
Rags
1
Park your vehicle in a semi-dark location such as a garage. Leave the door partly open and the vehicle's exhaust pipe pointing outside. Shift into park or neutral, depending on your vehicle type. Set the emergency brake and open the bonnet. Place the positive lead of a multimeter on the positive terminal of the car battery. Place the negative lead of the meter on the negative battery post.

2
Adjust the scale to "Volts" and read the meter. Any reading of below 12 volts indicates low battery voltage. Charge the battery to bring it up to maximum charge. An undercharged battery will not send proper voltage to the sensors, fuel pump, injectors and ignition system, which can cause an engine miss -- thus, it's important to rule out the battery before going on to other troubleshooting steps.

3
Hook up a tachometer lead to the negative post on the ignition coil or to the trigger signal post on your coil pack, if your vehicle is equipped with electronic ignition. Refer to your owner's manual for the exact location of the coil pack wire. Hook the other tachometer lead to an engine ground source. Fill a spray bottle with water. Start the engine and let it reach normal operating temperature.

4
Start at one plug wire location near the spark plug and spray water over the entire length of the plug wire up to the distributor cap. Look for any blue-white arcing sparks coming out of the wire and listen for electrical crackling or popping noises. Watch for signs of the engine cutting out or missing. See if an rpm drop occurs on the tachometer gauge. Proceed to the next wire, wet it down and repeat this step.

5
Spray test each plug wire, one by one, following the procedure described in the preceding step. If you find a wire that arcs and shows a miss, turn off the engine and wrap a piece of masking tape around the wire to mark it. Start the engine again. Spray water on top of the distributor. Look for arcing sparks between the distributor poles or from the pole necks to the distributor cap body. Any sparks indicate a carbon crack in the distributor casing. Use tape to mark any pole that emits an electrical arc, but shut the engine off first.

6
Spray a mist of water over the top and sides of the ignition coil or coil pack, depending on your vehicle. Ignition coils typically crack and emit sparks at the top pole neck, just under the rubber boot. Look for arcs on the coil pack between the plug wire connectors.

7
Spray water over the tips of the fuel injector heads. If the fuel-injector wire connectors have cracks, they will transfer voltage to ground and emit blue-white arcs. You will see a noticeable drop in rpm on the tachometer and notice an engine miss. Replace wires, connectors and components evidencing obvious electrical shorts. Use rags to wipe up any puddled water on the engine surfaces.

Tips and warnings

Water is an excellent conductor of electricity. It will travel through any cut or frayed wire to a ground source. Check all of the rubber boots on the spark plug wires for cracks and proper fit. Some boots melt from extreme exhaust heat. Replace all cracked and melted plug wire boots.
Although inspecting for electrical shorts in a semi-darkened garage is helpful for seeing electrical arcing, make sure you have proper ventilation for exhaust gases from the tailpipe of your vehicle. Use a large box fan to expel carbon monoxide and other dangerous fumes.

SOME OF THIS IS APPLICABLE or spray mist of water at night with both coils running to see if it is missing due to faulty HT leads it might just be one lead

m3vs911

Thanks, it is just one lead causing problem, however he mentioned that since the car has already been running for 20 years, if one lead start to have problem, it is good to do the whole set to eliminate similar problems in the future.

and as well as the spark plugs , dis. cap and rotor arms.

he has replaced the new chip in and take the car for a test drive, sound perfectly fine.

planned to be done by tomorrow evening, can't wait to test the car with the new chip and stuff finally !
it has been 2 weeks!

m3vs911

i think i've do inspected everything and a test drive before calling me to confirm that.

well yea, the last mech didn't seen this and claimed that my problem is tricky and have not been seen before.