Problem...no spark...need diagnosing help

[ae1969]

http://www.clarks-garage.com/shop-manual/fuel-05.htm

Read

and read the other sections of his site. It will slowly come clear.

Troubleshooting is a step wise process. You are lost because you are not listening to the advice given.

You had 2 of the BEST 944 guys replying to your post. Socal and AF but you are going off doing your own thing.

There is some reason to there madness. Trust me.

There is a section in clarks write up that will allow you to bypass the relay. IF it works ..........REPLACE IT .....dont drive with the jumpers in place.

[Makenzie71]

Thanks for the link but what the hell??

Originally posted by ae1969
You are lost because you are not listening to the advice given.

You had 2 of the BEST 944 guys replying to your post. Socal and AF but you are going off doing your own thing.

So let's see...Socal didn't give me advice toward my problem so what did he tell me that I'm not listening to?

Then there's Af who said...

You got water in the engine compartment - don't do that.

duh...but that's hard when it's raining and I'm having to drive through standing water...

Check the coil - make sure there is no water in the central post

Did that, it works.

Check cap and rotor - no water allowed there either.

Did that, it works.

Check the speed and reference sensor connectors - make sure they are not wet.

Did that, it works.

Check your coil connections
AFJuvat

Did that, it works.

The only thing I can't do is:

Change your DME relay.

Not everyone lives next door to a Porsche dealer or parts supplier. I can't just run out and ****ing get one...

...so maybe you can tell me what's been given to me that I'm not listening to?!

And bypssing the relay circuit with jumpers is called a test...

damn I'm so ****ing tired of people acting like I'm a 10 year old moron who's never turned a wrench. I'm listening to ALL the advice given to me and I'm still ****ing lost. Thank you.

[ae1969]

Mak relax ? don't take it personally.......but on the same day you posted this question you were also giving advice to seaboltman on how to set up a push button start on these cars....... Why?......who knows and I dont care...... but you seemed to me on that post that you had the ignition system under control. So i did not bother posting to this post.....

Since you are not listening to my advice ....... read some more. http://www.clarks-garage.com/shop-manual/eng-15.htm

AFJuvat was working you to the most LIKELY solution he works on these DAILY for a reason.

NO START conditions listed below (as clarks manual dictates)........ do you see some resemblance to what AF was getting to.

* DME Control Unit
* DME Relay
* Security System Control Unit
* Fuel Pump
* Fuel Pump Fuse
* Distributor Cap, Rotor, Coil, or Primary Coil Wire
* Engine Speed and/or Reference Sensors

If you dont know how to use a multimeter then yes ........THE JUMPER CABLE IS THE TEST. If it starts.......voila. DME Relay.....

Rigging other relays to test the situation is a waste of time if the jumper works......

[Makenzie71]

Don't take it personally? You're STILL insisting that I'm just not listening to anyone... And what does ANY of this have to do with anything I told Seaboltman?

AF was trying to help and I was listening to him. How was I not? I already ****ing asked that...

[Makenzie71]

and replacing the DME/FP relay with two generic $2 relays with identicle properties is not "rigging"...but beings I'm supposed to just walk out and go get a genuine relay maybe you can tell me where the hell I'm supposed to get it?

[AFJuvat]

Ok, do this

Leave the relay in place, pop the plastic cover off.

You will now see the 2 relays inside the relay body.

Have someone start the car while you watch the 2 relays

Both of them have to close.

If one isn't closing: close the contacts and hold them closed with a small piece of cardboard (tip: this will get you home if your relay dies on the road)

See what happens then - if you are up and running, great, if not, it is time to start looking at other options. Would go with fuel pressure or DME.

Have you tried swapping the coil?

Sorry, the crystal ball is still out for polishing, when you have your location as "Texas.... all of it" I have no idea where you are or what your proximity to a dealer is. As a side note, Pelican ships to just about anywhere, a Porsche dealer will ship to you remotely as well. If your order is over $50 they will overnight it to you.

From the pictures of your cars in the past, you seem to be somewhat rural, but hell, that was 10 minutes outside San Angelo or 30 minutes outside San Antonio when I lived there.

AFJuvat

[Makenzie71]

I gave the relay a good looking over and maade sure the contacts weren't corroded and that none of the components were blown or disconnected. I tried forcing the fuel contect shut to get her started but without success. I removed the relay completely and installed a jumper to the appropriate terminals and still got nothing.

I tried three different coils...

I don't have access to an adequate F/PSI guage at the time. If there anyway to test the DME other than replace it with a working unit?

I thought the "crystal ball" comment was referring to something else. My misunderstanding. I live way the hell up in the Northern Panhandle...the people who live out in the sticks say I live out in the sticks.

[AFJuvat]

PM me your email address

I'll send you the diagnostics procedures

AFJuvat

[Makenzie71]

Thanks!

[AFJuvat]

It is a 6 MB document, you will need adobe acrobat reader to use it

AFJuvat

[Makenzie71]

no problem

[ae1969]

Originally posted by Makenzie71
I
I don't have access to an adequate F/PSI guage at the time. If there anyway to test the DME other than replace it with a working unit?

Unfortunately no. Swapping is the only way.

Follow the steps that AF sent. Post your results. It will help others in the future.

If by chance it is the dme a slight tap may get it going. WHile you are checking the dme (underneath the floor board on the passengers side). Check for moisture. Dme does not like water.

P.S ....and I didnt mean to sound like I am riding your ass Mak. The internet is a tough medium to convey your tone.

[Makenzie71]

For four days now I've been listening to people tell me the same thing over and over and over again and when their advice doesn't work they insist that I just didn't do what they said...I'm sorry if I'm losing my appreciation of it.

[ae1969]

Ok......... I realize you dont have all the tools on you to check this stuff out...... and I will stop assuming that you dont have a clue.

Lets start from step 1. WHile you wait for Af's stuff.

No start.

1. Confirm Timing.
2. Confirm Spark.
3. Confirm Fuel.

1. Are you able to align the timing marks. 1 on the camshaft housing, 2nd on the back of the engine (flywheel inspection hole). If they dont align you have bigger problems.

2. So for spark check at the coil while someone cranks..... then check at the plugs. Even if you have spark I would pull the distributor to check the condition of the rotor (known to come loose), crack cap etc.....

3. You mention you could hear the fuel pump running.... but we we cant confirm fuel pressure (no fuel pressure guage) ........can we confirm the injectors are actually firing?
- you can use a noid light to check the injectors
- you can pull the rail and crank the car..... nice spray of gas out of all injectors.....

What tools do you have access to?
Tell us what you find.

...and relax I know this can be frustrating we have all been there. Let me buy you a beer.

[Makenzie71]

Thanks AF. I'm reading up on all of that now. Saw something again there, though, that makes me ask this question yet again:

I have power to the coil. Primary resistance on the coil is .6 ohms. Secondary resistance is in spec, too (can't remember what it was but I was testing it while reading the book and it was in spec). Turning the car over gets spark from the coil. Turning it over gets spark to each of the spark-plugs.

Being as that the DME grounds the coil to produce spark, I can only assume that the DME is getting power and functioning. Is this a correct assumption?

I'm going to go test fuel right now.

[Makenzie71]

Plugs were all gapped at .050. Book calls for between .070 and .080. I changed them all to roughly .075. No change in starting.

[ae1969]

Ok.... so you have spark. If you read into some of Clarks tech documents and AF documents you will see that the reference sensor must be gapped and working properly to actually have spark. The reference sensor picks up a signal from a pin on the flywheel. The dme uses that signal to ground out the coil and fire a spark. So in your case we will assume that the reference sensor and coil are good.

Side note 1: The one thing you want to check even though you are getting spark at the plugs is that the rotor is still intact. A few cases of the rotor coming loose. It will fire but obviousy not when you need it to.

Side note 2: The Dme is a funny little creature. Determining a bad DME is like differential diagnosis in the medical field. Assume everything and if you are just left with the DME .........swap and test. When you come to this point you have tested all sensors/inputs to the dme. If they all check out you have to assume the DME at that point. We are not at that point just yet.

Keep going.....

[ae1969]

- Things to check out at this point. (do we have fuel? are the injectors firing?)

FPR (fuel pressure regulator) - Unplug one injector and see if it starts. When the FPR goes bad (strangely enough frequently in these cars) the high pressure keeps the injectors from firing. The high fuel pressure makes the injectors draw quite a bit of current causing the injector driver in the DME to shut down. So if the car runs with 3 injectors......... you have a bad FPR

Fuel injectors firing: Are they? A noid light would be great at this point. But we can also check voltage to see if they are getting power at least. Unplug one injector plug at a time and turn the ignition key to on. You should have 12 volts on one pin and 0 on the other.

Side note 1 : when you gapped the plugs did you smell fuel? They should of been nicely soaked at this point with all the cranking?

[Makenzie71]

I didn't have time to pull the rail and check the spray. I DID, however, spray some B12 into the intake with the 87/30 jumper in place (DME has power, fuel pump does not). I still had spark but the engine never hit. It was just a fleeting idea to try and I did it in a hurry so I may have botched something...I'll try the injector thing tomorrow. I know fuel is circulating, but that's all I could be sure of right now.

I guess the "still time" is at least giving me time to work on my headlamp molds...

[carsontc]

curious...do you know how old is the DME / Fuel Pump relay is ?

the distributor cap ?

the rotor ?

the spark plug wires ?

the fuel filter ?

if the answer to any of these is more than 5 years...you are taking chances

most worry about oil changes, air filter, spark plugs and with hope, timing belts

these other bits can and will bite you if ignored