964 Engine Rebuild
09-24-2006, 03:36 AM
#196
Three Wheelin'
Thread Starter
Jason,
-My car in a 1989 model, so there is no airbag.
-I read the part about pin 85 of the DME relay, but I think that means that if you have no power at the DME with the ignition on, make sure that power to the DME is not being held out by the alarm system.
My DME relay definetly has power. I jumpered it out at one point across pins 3/5/7 to enable the fuel pump and energize the DME.
Enough for tonight I guess. tomorrow is a new day.
Kirk
-My car in a 1989 model, so there is no airbag.
-I read the part about pin 85 of the DME relay, but I think that means that if you have no power at the DME with the ignition on, make sure that power to the DME is not being held out by the alarm system.
My DME relay definetly has power. I jumpered it out at one point across pins 3/5/7 to enable the fuel pump and energize the DME.
Enough for tonight I guess. tomorrow is a new day.
Kirk
09-24-2006, 01:13 PM
#198
Three Wheelin'
Thread Starter
All questions welcome at this point!
Starter is attached with 2 mainleads and one small one to the solenoid. Car turns over fine. Just no spark. (Well and maybe the injectors aren't firing either. I havent looked that far yet)
Kirk
Starter is attached with 2 mainleads and one small one to the solenoid. Car turns over fine. Just no spark. (Well and maybe the injectors aren't firing either. I havent looked that far yet)
Kirk
09-24-2006, 06:10 PM
#199
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Excuse me for jumping in at last minute -- and I admit I don't know a lot about Porsches -- but in another German car I own (that had a Throttle Position Sensor), when I rebuilt the engine and reinstalled it, it wouldn't deliver a spark either. Turned out that the TPS was jammed open (simulating a Wide Open Throttle). The computer turns off fuel when it senses a WOT. Once reset, the engine fired right up. Check that you've correctly installed the throttle linkage or, if the car has a TPS, check the voltage to it.
09-24-2006, 06:29 PM
#200
Burning Brakes
i think if your coil switches are plugged in reversed (primary to secondary and secondary to primary) the engine will not run. i could be wrong as i'm going by memory but i know there's something weird that happens in some configuration that you would not expect. i'll look back at my posts and try to recall.....
09-24-2006, 07:26 PM
#201
Three Wheelin'
Thread Starter
Doug,
Well thats an interesting point. Which coild should get plugged into the primary distributor?
-Right now I have the coil closest to the firewall (front of car) plugged into the primary upper distributor.
-All fuses in the car are good (front fuse box and rear fuse box next to coils)
-Bosche hammer does not see the DME. But I am not sure if it ever did. And I think there is some precedence where the hammer would not talk to the DME, but the car ran fine.
-All wiring plugged in, including the two big connectors with the pins, distributor, coil plugs, etc.
-checked distributor wiring. The red wire from the hall effect goes to (+), black wire to (-)
-DME is receiving battery power, and power through the DME relay with the ignition switched on.
Sadly I leave town for the next four days, so it looks like this car wont be starting this weekend.
Sigh
Kirk
Well thats an interesting point. Which coild should get plugged into the primary distributor?
-Right now I have the coil closest to the firewall (front of car) plugged into the primary upper distributor.
-All fuses in the car are good (front fuse box and rear fuse box next to coils)
-Bosche hammer does not see the DME. But I am not sure if it ever did. And I think there is some precedence where the hammer would not talk to the DME, but the car ran fine.
-All wiring plugged in, including the two big connectors with the pins, distributor, coil plugs, etc.
-checked distributor wiring. The red wire from the hall effect goes to (+), black wire to (-)
-DME is receiving battery power, and power through the DME relay with the ignition switched on.
Sadly I leave town for the next four days, so it looks like this car wont be starting this weekend.
Sigh
Kirk
09-24-2006, 08:05 PM
#202
Burning Brakes
actually i'm out of town so i can't look. i'm pretty sure the coil that's closest to the firewall goes to the primary dist.
it's the switches that plug into each coil that must be correct. i doubt you ever unplugged them during your rebuild..........
you might try starting the engine on the secondary dist only (unplug the primary switch). if something is arcing and freaking out the system (it happens) they (mine) still ran on the secondary but wouldn't run on both
it's the switches that plug into each coil that must be correct. i doubt you ever unplugged them during your rebuild..........
you might try starting the engine on the secondary dist only (unplug the primary switch). if something is arcing and freaking out the system (it happens) they (mine) still ran on the secondary but wouldn't run on both
09-24-2006, 10:05 PM
#203
Three Wheelin'
Thread Starter
A couple of pics.
Scope trace of signal from flywheel sensor.
Some pics of left side of engine compartment.
(O2 wire is not connected on these)
Kirk
Scope trace of signal from flywheel sensor.
Some pics of left side of engine compartment.
(O2 wire is not connected on these)
Kirk
09-25-2006, 10:29 PM
#204
Three Wheelin'
Thread Starter
Well as long as we have the whole week to talk about it, I should probably post another thread to figure out what the minimum requirements are for 'spark'
As I see it:
-The DME must be functional (I dont know any way to test this except put it in a different car)
-The DME must be getting battery power, (At DME connector Pins 24-18 have ~12 Volts with key off)
-The DME must be getting switched ignition power from the DME relay (At DME connector pins 24-37 have ~12 Volts with key on)
-The flywheel reference sensor must be functional (At DME connector pins 47-48 speed ref sensor input shows a signal > 3v p-p)
-The distributor hall effect sensor must be working. (I dont know how to check this)
-The distributor must be turning
-The coils must be ok
Then in my mind, there will be spark.
I dont think any other sensors are required for the DME to send its pulse to the coils. (Car may not run, but there will be spark)
???
I'll post this question in a new thread. See what everyone's opinion is:
Kirk
As I see it:
-The DME must be functional (I dont know any way to test this except put it in a different car)
-The DME must be getting battery power, (At DME connector Pins 24-18 have ~12 Volts with key off)
-The DME must be getting switched ignition power from the DME relay (At DME connector pins 24-37 have ~12 Volts with key on)
-The flywheel reference sensor must be functional (At DME connector pins 47-48 speed ref sensor input shows a signal > 3v p-p)
-The distributor hall effect sensor must be working. (I dont know how to check this)
-The distributor must be turning
-The coils must be ok
Then in my mind, there will be spark.
I dont think any other sensors are required for the DME to send its pulse to the coils. (Car may not run, but there will be spark)
???
I'll post this question in a new thread. See what everyone's opinion is:
Kirk
10-09-2006, 11:23 PM
#205
Three Wheelin'
Thread Starter
Update:
Ok I purchased another DME from an auto wrecker in Toronto, and it arrived this week.
I installed it and the car starter almost immediately. Yay.
I have no idea why the old DME died.
I spent the weekend doing the initial breakin on the engine, and so far its looking pretty good. There is an oil leak from somewhere around the thermostat housing, an oil leak from the oil tank level sensor (Not sure why, maybe it was always leaking there. I never had it out) and initially there was a leak from the power steering pump seal, but it may have seated itself and stopped. Time will tell.
I have put about 200 km on the car so far.
The clutch works fine, no problems there. I don't notice alot of difference between the DMF and the LWF. The idle is still slightly unstable despite the system adaptation using the hammer.
Engine feels a little rough to me, and a bit boggy at lower RPMs. I can't decided whether it feels rough because of the new solid engine mounts or because of a running problem.
With the hammer attached, I can't find anything that looks out of place. All the sensors are reading ok, and changing as you would expect. The idle and WOT switches are making, O2 sensor is reading, etc. Knock numbers are in the 0-20 range when you do the knock check. Both coils are firing and the car will run on either distributor.
I have to fix the leak at the oil thermostat before I do much more driving. So I will probably get to that in the morning.
The exhaust with the cat bypass and cup pipe is a little loud, but not too outrageous.
Overall things are going pretty well, except for the impression I have that the engine is hesitating/crossfiring/missing at idle & low revs. Power seems a little off to me, but its hard to judge during breakin.
Kirk
Ok I purchased another DME from an auto wrecker in Toronto, and it arrived this week.
I installed it and the car starter almost immediately. Yay.
I have no idea why the old DME died.
I spent the weekend doing the initial breakin on the engine, and so far its looking pretty good. There is an oil leak from somewhere around the thermostat housing, an oil leak from the oil tank level sensor (Not sure why, maybe it was always leaking there. I never had it out) and initially there was a leak from the power steering pump seal, but it may have seated itself and stopped. Time will tell.
I have put about 200 km on the car so far.
The clutch works fine, no problems there. I don't notice alot of difference between the DMF and the LWF. The idle is still slightly unstable despite the system adaptation using the hammer.
Engine feels a little rough to me, and a bit boggy at lower RPMs. I can't decided whether it feels rough because of the new solid engine mounts or because of a running problem.
With the hammer attached, I can't find anything that looks out of place. All the sensors are reading ok, and changing as you would expect. The idle and WOT switches are making, O2 sensor is reading, etc. Knock numbers are in the 0-20 range when you do the knock check. Both coils are firing and the car will run on either distributor.
I have to fix the leak at the oil thermostat before I do much more driving. So I will probably get to that in the morning.
The exhaust with the cat bypass and cup pipe is a little loud, but not too outrageous.
Overall things are going pretty well, except for the impression I have that the engine is hesitating/crossfiring/missing at idle & low revs. Power seems a little off to me, but its hard to judge during breakin.
Kirk
10-10-2006, 12:24 AM
#208
Technical Guru
Rennlist Member
Rennlist Member
Originally Posted by KirkF
Knock numbers are in the 0-20 range when you do the knock check.
