86 ROW ignitio wire query
06-02-2014, 08:54 AM
#16
Addict
Rennlist Member
Rennlist Member
Join Date: Oct 2003
Location: Gone. On the Open Road
Posts: 16,409
Received 1,589 Likes
on
1,037 Posts
Have you verified that the injectors are actually being pulsed?
06-02-2014, 01:05 PM
#17
Inventor
Rennlist Member
Rennlist Member
If the CPS is new and it's connector is good, then it could be the EZ EPROM/chip holder solder connection to the board, which is often weak. Reflow the joints.
For an intermittent no start or stutter, rapping on the steel EZ cover while idling (EG. with the handle end of a screwdriver) will usually show if this is the problem.
For an intermittent no start or stutter, rapping on the steel EZ cover while idling (EG. with the handle end of a screwdriver) will usually show if this is the problem.
06-02-2014, 11:02 PM
#18
It sounds to me that the EZ-F may be having problems synchronising to the gap in the timing gear teeth. This is the usual cause of EZ-F failure. I assume the car only runs briefly and then cuts out ?
I suggest you borrow a known good EZ-F from another owner, or Matt Nicholson will probably be able to offer you one on a sale or return basis.
I suggest you borrow a known good EZ-F from another owner, or Matt Nicholson will probably be able to offer you one on a sale or return basis.
John, I'm sending this one to you when it get it over to Roger and looking forward to hearing what you find.
06-04-2014, 02:57 AM
#19
Rennlist Member
Thread Starter
Join Date: Nov 2011
Location: Adelaide, South Australia
Posts: 721
Likes: 0
Received 78 Likes
on
42 Posts
Well, just put in a new crank angle sensor and no difference.
Swapped the EZF for a known good one, no difference. Even swapped the LH box, no difference.
It tries to start, just but won't. Still sounds to me like it is too far advanced.
I'm now looking for a can of fuel and a box of matches!
Swapped the EZF for a known good one, no difference. Even swapped the LH box, no difference.
It tries to start, just but won't. Still sounds to me like it is too far advanced.
I'm now looking for a can of fuel and a box of matches!
06-04-2014, 02:58 AM
#20
Rennlist Member
Thread Starter
Join Date: Nov 2011
Location: Adelaide, South Australia
Posts: 721
Likes: 0
Received 78 Likes
on
42 Posts
Well, just put in a new crank angle sensor and no difference.
Swapped the EZF for a known good one, no difference. Even swapped the LH box, no difference.
It tries to start, just but won't. Still sounds to me like it is too far advanced.
I'm now looking for a can of fuel and a box of matches!
Swapped the EZF for a known good one, no difference. Even swapped the LH box, no difference.
It tries to start, just but won't. Still sounds to me like it is too far advanced.
I'm now looking for a can of fuel and a box of matches!
06-05-2014, 05:47 AM
#21
Rennlist Member
Thread Starter
Join Date: Nov 2011
Location: Adelaide, South Australia
Posts: 721
Likes: 0
Received 78 Likes
on
42 Posts
More testing today, working through the WSM test procedure and EVERYTHING falls well within the specs Porsche list.
Hooked 2 spark plugs, one to each coil lead, with a 4mm gap and put 12 volts onto the green and white trigger wires above the CEB as detailed in the WSM and got big fat rhythmic sparks from each side.
Put a fuel pressure gauge on the test point, cranked the starter over and got full pressure after just a few cranks.
Put the O. Silly Scope on and proved the new crank angle sensor is fine.
Where do I go from here? Heeeeeelp!
Hooked 2 spark plugs, one to each coil lead, with a 4mm gap and put 12 volts onto the green and white trigger wires above the CEB as detailed in the WSM and got big fat rhythmic sparks from each side.
Put a fuel pressure gauge on the test point, cranked the starter over and got full pressure after just a few cranks.
Put the O. Silly Scope on and proved the new crank angle sensor is fine.
Where do I go from here? Heeeeeelp!
06-05-2014, 09:44 AM
#22
Nordschleife Master
So you have fuel pressure and spark.
Did you try a noid light on an injector to make sure they're pulsing? (i.e. no short or break in that harness).
Also, some silly questions. Did you check the distributors pointed the right way when doing the belt, and that it wasn't TDC on #6? Is the harmonic damper around the right way? (not a problem which directly prevents running, but sometimes people set timing with it facing the wrong way, which puts things out a lot).
Did you try a noid light on an injector to make sure they're pulsing? (i.e. no short or break in that harness).
Also, some silly questions. Did you check the distributors pointed the right way when doing the belt, and that it wasn't TDC on #6? Is the harmonic damper around the right way? (not a problem which directly prevents running, but sometimes people set timing with it facing the wrong way, which puts things out a lot).
06-05-2014, 10:22 AM
#23
Addict
Rennlist Member
Rennlist Member
Join Date: Oct 2003
Location: Gone. On the Open Road
Posts: 16,409
Received 1,589 Likes
on
1,037 Posts
06-05-2014, 09:00 PM
#24
Rennlist Member
Thread Starter
Join Date: Nov 2011
Location: Adelaide, South Australia
Posts: 721
Likes: 0
Received 78 Likes
on
42 Posts
So you have fuel pressure and spark.
Did you try a noid light on an injector to make sure they're pulsing? (i.e. no short or break in that harness).
Also, some silly questions. Did you check the distributors pointed the right way when doing the belt, and that it wasn't TDC on #6? Is the harmonic damper around the right way? (not a problem which directly prevents running, but sometimes people set timing with it facing the wrong way, which puts things out a lot).
Did you try a noid light on an injector to make sure they're pulsing? (i.e. no short or break in that harness).
Also, some silly questions. Did you check the distributors pointed the right way when doing the belt, and that it wasn't TDC on #6? Is the harmonic damper around the right way? (not a problem which directly prevents running, but sometimes people set timing with it facing the wrong way, which puts things out a lot).
Yes to timing etc.
The thing is that it has started and run very well.
06-05-2014, 09:11 PM
#25
Rennlist Member
Thread Starter
Join Date: Nov 2011
Location: Adelaide, South Australia
Posts: 721
Likes: 0
Received 78 Likes
on
42 Posts
Dave, the injector checking is a real pain on these engines as I'm sure you know.
I don't have any means of checking them YET but it is certainly that time I agree. I have an oscilloscope but how do you hook that up and test an engine that fires but won't start?
The injectors were sent to a local FI shop for o/h and all passed testing with flying colours.
Because the engine was out of the car to repair the fire damage, the engine loom [injectors ect] was replaced, complete and refitted to the engine while it was out. A lot of checking and rechecking was done then.
Then all was re-assemble and it ran and drove?
Interestingly in the WSM Porsche say 'run the engine and remove one injector plug at a time'. Well really Fritz, have you looked under the bonnet of one of these? You can't even see the injector plugs until the plenems are off.
I don't have any means of checking them YET but it is certainly that time I agree. I have an oscilloscope but how do you hook that up and test an engine that fires but won't start?
The injectors were sent to a local FI shop for o/h and all passed testing with flying colours.
Because the engine was out of the car to repair the fire damage, the engine loom [injectors ect] was replaced, complete and refitted to the engine while it was out. A lot of checking and rechecking was done then.
Then all was re-assemble and it ran and drove?
Interestingly in the WSM Porsche say 'run the engine and remove one injector plug at a time'. Well really Fritz, have you looked under the bonnet of one of these? You can't even see the injector plugs until the plenems are off.
06-05-2014, 09:29 PM
#26
Team Owner
to test the injectors for firing,
remove the plenums,
install the noid light on one injector wire at a time,
crank the engine, a helper is a good thing.
also another way figure this is to spray some ether into the intake then crank it ,
if it fires then you have fuel delivery issue.
It would also be a great idea to replace the damaged harnesses with used parts from a good donor car.
928 INTL has good used wires
remove the plenums,
install the noid light on one injector wire at a time,
crank the engine, a helper is a good thing.
also another way figure this is to spray some ether into the intake then crank it ,
if it fires then you have fuel delivery issue.
It would also be a great idea to replace the damaged harnesses with used parts from a good donor car.
928 INTL has good used wires
06-05-2014, 10:20 PM
#27
Addict
Rennlist Member
Rennlist Member
Join Date: Oct 2003
Location: Gone. On the Open Road
Posts: 16,409
Received 1,589 Likes
on
1,037 Posts
Easier with a noid light, but a scope works too.
Last edited by worf928; 06-06-2014 at 10:43 AM.
06-09-2014, 06:02 AM
#28
Rennlist Member
Thread Starter
Join Date: Nov 2011
Location: Adelaide, South Australia
Posts: 721
Likes: 0
Received 78 Likes
on
42 Posts
Disassemble the LH plug: Remove the three screws keeping it together. Then push the plug cover away from the plug to expose the back side of the pins. Plug back into LH with pins exposed. Probe the pin that carries the ground from the injectors.
Easier with a noid light, but a scope works too.
Easier with a noid light, but a scope works too.
I've been away for a few days, time to get back into it.
i really appreciate all this help. Many thanks.
06-11-2014, 07:48 AM
#29
Rennlist Member
Thread Starter
Join Date: Nov 2011
Location: Adelaide, South Australia
Posts: 721
Likes: 0
Received 78 Likes
on
42 Posts
Well she runs again!!!!!
It seem the purpose of the mystery ignition trigger extension 928.612.033.00 is to swap the green and white wires over. That is, green to white and vice versa.
It would normally be hard to get his wrong as the 2 pin plug has a 'key' on it to prevent incorrect connection but one of these plugs was broken so we assumed [wrongly] that they connect colour for colour.
Anyway she now purrs like a kitten and roars like a lion.
Thanks again for all of your help.
It seem the purpose of the mystery ignition trigger extension 928.612.033.00 is to swap the green and white wires over. That is, green to white and vice versa.
It would normally be hard to get his wrong as the 2 pin plug has a 'key' on it to prevent incorrect connection but one of these plugs was broken so we assumed [wrongly] that they connect colour for colour.
Anyway she now purrs like a kitten and roars like a lion.
Thanks again for all of your help.
