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Engine Drop Time Lapse

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Old 01-09-2012, 10:17 PM
  #91  
TravisB
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Originally Posted by IXLR8
Send me a plane ticket...I've never been to Seattle.

OK, you forgot one connector; did you possibly forget any others. Two basic things won't make a car run...fuel and spark...and you seem to have both...at the same time, I hope.
Trust me, it's tempting...can you leave tonight?

As for the wires, seeing how hard it is to access everything once it's back in the car I made sure to have everything connected and double-triple checked. The loose wire I actually noticed when I was putting the intake back on, but figured it must go to the chassis somewhere. Then it went back in and I ran out of things to connect to..obviously I missed something somewhere, but my eyes aren't picking it up.


Originally Posted by GC96
Do you have access to the Durametric software or an equivalent scanner to see what codes are being thrown? It might be a sensor issue. I'm not familiar with the Porsche Motronic Engine management system, but in similar VW/Audi ones there are usually one or two sensors without which the system will not run. The first one that comes to mind is the crank position sensor, I think on the '95 Porsche wiring diagram its called out as the engine speed sensor. Also I don't recall if you mentioned it, but you might check the cylinder head temp sensor as well, if it is bad it could tell the ECM could flood the engine.

GC

Nope, no access to any of that fun stuff. The temp sensor was mentioned by the shop I talked to, he said it's very, very unlikely that it's the cause if it was running fine before. Is there any way to test these sensors rather than just semi-blindly throwing parts at it?

I think at this point I am just going to get it back in to rolling-condition and have it towed in to the pro's..although after towing and such I could replace one or both of those sensors. And probably still not solve the mystery..
Old 01-09-2012, 10:24 PM
  #92  
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Travis, you have a PM to a link for the electrical diagrams.

Another thing, make sure your connectors are actually "fully on".

The first winter I had my 993, I replaced the valve cover seals, spark plugs, and had the complete exhaust system off to replace gaskets and fasteners. I had taken off some fuel injector connectors and when I put them back on, I simply pushed them back on thinking they would snap into place (like shutting a door). Upon start-up, I was running on 5 cylinders. Lucky me, I reached in and checked those connectors...sure enough, one pulled right off. I had to depress the spring clip, slide it on and then release the clip...then it was fully on and making contact...back to 6 cylinders running.
Old 01-09-2012, 11:38 PM
  #93  
Mike J
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You can pull pull an injector, put it in a container when hooked up (you will need to pull the fuel rail, left hand one would be easier) and see if fuel is squirting. However, with wet plugs, its sounds good.

You said timing was "close". The rotor should be bang on #1 position under the cap when the marker is on TDC on the flywheel pulley. If you are one notch out on the gearing, it could appear to be close but it will be out enough to miss TDC. You might get some burping though.

Ok, here are some more ideas off the top of my head.

1 - Check the injectors have fuel. Undo the main fuel line to the right hand fuel rail slowly - is gas dripping out?

2 - Check the main wiring harness connections on the left hand side of the engine bay. Its easy not to seat the injector connectors, hence no power to the injectors. Take them off, reseat and make sure the safety clips are locked in.

3 - You did not change any timing, correct? It still sounds like something in the timing, which can only be the distributor. The distributor is plugged in, right?

4 - You have the correct coil to the correct distributor, correct?

5- Replace the DME relay. Perhaps it blew?

6 - Check all the fuses, especially those for the fuel pump and injectors/ignition.

7 - You said the it will not blip when you use a spray cold start solution, right? That implies ignition. Double check again, pull the #1 top plug, put the engine just below TDC, have ignition on, and slowly turn the engine over. Does it spark exactly when TDC is hit? (this is very dangerous though - their is small change the engine will fire up. small.)

8 - Grounds straps on? double check all connectors. Air metering hooked up?

9 - I agree, read codes if you can. I have a PST-2, so I would be at an advantage, but take a look with any tool you can.

Keep at it, it will look pretty stupid when you find it, but you will feel great when it starts up.

Cheers,

Mike
Old 01-10-2012, 12:45 AM
  #94  
TravisB
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Originally Posted by Mike J
You can pull pull an injector, put it in a container when hooked up (you will need to pull the fuel rail, left hand one would be easier) and see if fuel is squirting. However, with wet plugs, its sounds good.
Yeah, figure wet plugs and strong gas smell means it's getting fuel..

You said timing was "close". The rotor should be bang on #1 position under the cap when the marker is on TDC on the flywheel pulley. If you are one notch out on the gearing, it could appear to be close but it will be out enough to miss TDC. You might get some burping though.
Well, the deal with the timing is that the car ran fine before, and I did not remove the distributor...the belt was done by a local shop at 60k (until now they've been maintaining it since it got to WA with 22k on the clock). I doubt they'd let it out of their hands with something being off, but I thought I'd do a quick check. What I meant by being slightly off, the timing mark was about 3/4" or so to the left of the TDC marker on the fan housing..both valves were closed, and the rotor was pointed "almost" to the #1 position. I figure if it's off, it's not by much at all, and wouldn't be the cause of a non-starting, non-burping/backfiring situation. All I did was change out the plugs, leads and caps/rotors.

2 - Check the main wiring harness connections on the left hand side of the engine bay. Its easy not to seat the injector connectors, hence no power to the injectors. Take them off, reseat and make sure the safety clips are locked in.
Double checked and I removed and reinstalled them after that..

3 - You did not change any timing, correct? It still sounds like something in the timing, which can only be the distributor. The distributor is plugged in, right?
All I did was plugs, leads and cap/rotor. And it's plugged in.

4 - You have the correct coil to the correct distributor, correct?
Yep, when I checked for spark I checked each one, and both coils are getting voltage..

5- Replace the DME relay. Perhaps it blew?
That was the first thing I tried..

6 - Check all the fuses, especially those for the fuel pump and injectors/ignition.
Fuses all checked out.

7 - You said the it will not blip when you use a spray cold start solution, right? That implies ignition. Double check again, pull the #1 top plug, put the engine just below TDC, have ignition on, and slowly turn the engine over. Does it spark exactly when TDC is hit? (this is very dangerous though - their is small change the engine will fire up. small.)
That scares me a little...with my luck, if it fires, it would be during this exercise, LOL.

8 - Grounds straps on? double check all connectors. Air metering hooked up?
Yep and yep..

9 - I agree, read codes if you can. I have a PST-2, so I would be at an advantage, but take a look with any tool you can.
Code reader would be fantastic but I lack one and I don't think I'd get too far limping it in using the starter. :-p I feel like that would be a big time saver, or at least eliminate some possibilities. Would anything that reads OBD-I work, or does it need to be Porsche specific?

Keep at it, it will look pretty stupid when you find it, but you will feel great when it starts up.
I am fully expecting to give myself a large bruise on my forehead when this gets figured out...but until now I guess I'll just continue to pull out what's left of my hair, heh.
Old 01-10-2012, 01:18 AM
  #95  
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I believe any scanner that reads OBD-I should work as long as you have the connector to connect it to the car. I think the '95s all have a round plug as opposed to the 16 pin plug that became the OBDII standard. I have used the VAG-COM (equivalent of Durametric for VW products) on my car to scan codes and do monitor some of the sensor readings. Unfortunately I do not have an adapter for the round plug otherwise I'd let you borrow it as it does read some OBD-I stuff as well.
For the temperature sensor you can check the resistance, it should be a function of temperature. The OBD-II diagnostic manual lists the following values:
-10 deg C = 8 - 11 k-ohm
20 deg C = 2 - 3 k-ohm
80 deg C = 260 - 390 ohm.
You should get a reading of probably around 5 kilo-ohms or higher assuming your garage isn't heated.

GC
Old 01-10-2012, 01:24 AM
  #96  
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Originally Posted by GC96
I believe any scanner that reads OBD-I should work as long as you have the connector to connect it to the car. I think the '95s all have a round plug as opposed to the 16 pin plug that became the OBDII standard. I have used the VAG-COM (equivalent of Durametric for VW products) on my car to scan codes and do monitor some of the sensor readings. Unfortunately I do not have an adapter for the round plug otherwise I'd let you borrow it as it does read some OBD-I stuff as well.
For the temperature sensor you can check the resistance, it should be a function of temperature. The OBD-II diagnostic manual lists the following values:
-10 deg C = 8 - 11 k-ohm
20 deg C = 2 - 3 k-ohm
80 deg C = 260 - 390 ohm.
You should get a reading of probably around 5 kilo-ohms or higher assuming your garage isn't heated.

GC
I got 2.9 k-ohms..garage is roughly 16-17*C so I think the temp sensor can be crossed off the list..
Old 01-10-2012, 01:36 AM
  #97  
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was the engine turned while the dizzy was out?

Double check that ground wire (0 gauge wire) at the starter housing?
Old 01-10-2012, 01:42 AM
  #98  
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Originally Posted by chris walrod
was the engine turned while the dizzy was out?

Double check that ground wire (0 gauge wire) at the starter housing?
It never left the block, the belt was done at 60k so I let it be. And yep, everything is connected in the starter area..probably wouldn't turn over too well without the ground hooked up.
Old 01-10-2012, 01:54 AM
  #99  
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I'm sure you've already checked but I'll ask anyway, have you double checked that the plug wires are connected to the correct terminals on the distributor caps? Since you didn't remove the distributor I would assume its' timing is the same as before you started the project, but if the wires are hooked up incorrectly then you would still see a spark when you check for it but it would be at the wrong time for the engine to actually run.

GC
Old 01-10-2012, 02:02 AM
  #100  
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Just one more thing to check.... When you put the flywheel sensor back in did you measure for the proper distance to the flywheel. I think it has to be something like 1 mm, plus/minus .2 mm. If this is off it will affect timing. And, you can get at it from under the car if need be. Ask me how I know.

My second suggestion is to re-check and make sure the ignition wires at the dizzy caps are per the diagram Alex provided a few posts ago. When I did this I got that wrong three separate times!

Keep at it, you'll eventually find what's wrong....

Best Regards, Peter
Old 01-10-2012, 02:06 AM
  #101  
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I think he said that he did not remove the distributor so that is off the diagnostics.

Maybe it would be good to quickly list exactly what you did remove, ie.

intake filter housing
intake metering system
intake manifold
intake stacks
main wiring harness
mufflers
cat converter
exhaust

Did you put in new plugs during the work? I.e. is it possible they were wet when you stopped the engine?

Did you remove the injectors?

Did you remove at least a plug per cylinder and clean/dry the plugs?

I did not see a reply if you reseated all the main harness connections to the electrical box on the left hand side of the engine compartment? Double check for bent pins too.

You are still not getting a least a stumble or some sort of ignition, correct? Its hard on two distributors to screw up the wiring, especially if you have not changed them.

Cheers,

Mike
Old 01-10-2012, 02:10 AM
  #102  
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Originally Posted by Vorsicht
Just one more thing to check.... When you put the flywheel sensor back in did you measure for the proper distance to the flywheel. I think it has to be something like 1 mm, plus/minus .2 mm. If this is off it will affect timing. And, you can get at it from under the car if need be. Ask me how I know.

My second suggestion is to re-check and make sure the ignition wires at the dizzy caps are per the diagram Alex provided a few posts ago. When I did this I got that wrong three separate times!

Keep at it, you'll eventually find what's wrong....

Best Regards, Peter
Good idea on the sensor - but he is getting a spark. That is why I suggested he try to get a spark at the right period. He also mentioned that he is getting a spark, I think if that sensor was out no sparky.

Cheers,

Mike
Old 01-10-2012, 02:23 AM
  #103  
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Originally Posted by Mike J
Good idea on the sensor - but he is getting a spark. That is why I suggested he try to get a spark at the right period. He also mentioned that he is getting a spark, I think if that sensor was out no sparky.

Cheers,

Mike
I was thinking it is perhaps too far away from the flywheel creating an erroneous signal to DME leading to timing error. Still worth checking....
Old 01-10-2012, 02:24 AM
  #104  
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Yup, great idea! Question is - did he muck with it or bump it ?

Travis, did you check the clearance before you put the transmission back on? When you had trouble with that last inch of installation, did it resolve easily? I did not see in the thread, new flywheel?

Did you check the connector (left hand side, front of the engine (towards the front of the car). there are three plugs, black, green, white. They are all plugged in, right?

Cheers,

Mike
Old 01-10-2012, 03:34 AM
  #105  
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Originally Posted by GC96
I think the '95s all have a round plug as opposed to the 16 pin plug that became the OBDII standard.
GC
Only the very early '95s have the round plug. my Nov '94 '95 has the ODBII connection with the ODBI system.


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