blown 944

If you have seen spark, chances are that the s/r sensors are working.
They typically work or not.

Have you done a compression test at all??

The tach bounces about a 1/8 inch when cranking.

If you truly are seeing spark I would.
1) verify fuel at injector again
2) leave plugs out and crank with the DME relay out or the fuse for the O2 sensor (FP as well)
3) do a compression test on all cylinders

If all checks out install new plugs and see if they smell gassy right away after putting all back together. If they do right away I would check the fpr or dampner and possible a MAF issue.

Ziff951

Sid, thanks for the info. The battery finally gave out and I have it charging now. Tomorrow I will do a detailed retest of everything.
-I definitely had spark at the coil, then at the #1 spark plug.

-I tested the fuel by pulling the rail and cranking it over a few times as it rested on the valve cover. I didn't have help, so I couldn't watch the spray or anything, but there was a nice wet spot under each injector. I'll try for a visual of the money shot tomorrow, maybe video it.

I will do a more thorough test tomorrow using your advice and see if I can find anything else out.

You think possibly a MAF issue? I haven't moved it or touched it during the work I did. Is this something that could have happened by an electrical short or something? maybe the dme got zapped? The green light turns on on the mafterburner box when I turn the key to accessory... would that mean the dme is okay?

The connector to the TPS looks a bit tired as well...could that be an issue? TPS seems to be adjusted properly. Maybe something happened during disassembly that messed up a connection?

I went ahead and ordered the s&r sensors anyway, as the wiring was in horrendous condition..(PO hack job)

I'll do the compression test also...

Thanks for the continuing support everybody, it really means a lot.

-Stephen

Rogue_Ant

The MAF shouldn't have any affect on actual starting...
Even if the MAF is bad, the car should start momentarily then die.
When cranking the DME does not use the MAF/AFM, rather it just uses a set value for airflow.


-Rogue

George D

I'll pay what I can for some help...so embarassing...I rebuilt my whole 74' Land Cruiser and can't get this stupid ignition problem figured out...grrrrrrrr...[/QUOTE]

Don't be embarassed. These cars are the most difficult cars to work on and diagnose I've owned. I must love a challenge, as I've had three.

Once you get this sorted, you will be happy again.

Ziff951

Thanks George...a little bump of encouragement is always good....With an 18 month old baby, fixer upper house, and trying to keep busy working, it gets tough to find time for the 'therapeutic' hobbies!... all will be good...one day...;-)

adrial

With the stock AFM, you can diagnose an AFM issue causing a no-start by unplugging it --- the car will still start and idle (but nothing else). I'm not sure how this MAF setup would respond, but it's worth a shot I think.

Ziff951

Okay...small setback. the starter died. I just got a new one in and decided to check the spark again (since it's dark out it's easier to see). I absolutely have a good spark. So, after reading a billion threads on this, I then pulled the fuel pump fuse and cranked it. It actually popped a couple times like it wanted to do something. That's the most it's done since the start of this. I think I'm headed in the right direction. So what do you guys think is next?
Is it getting too much fuel? I read on thread about someone's car starting without the fuel pump fuse in...I'll check that thread again... I think it ended up being bad wiring on the dme temp sender..I just replaced my sender, I'll check wires.
Maybe fuel damper dealio? Computer telling it to give too much fuel? But why now? I'm gonna start up with it again tomorrow...and read more threads.

Thanks everybody, I think we're getting close.

-Stephen

Ziff951

Temp sensor is good. resistance checked out, as per Clark's Garage. Need to replace fuel rail gauge and I'll check the situation there...too much/too little fuel...

Rogue_Ant

Let us know what you find out.

joeacc

i had exact same problem and my temp sensor wires were touching under the rubber boot so made the dme think car was hot and not start. just a thought

Ziff951

Hmm. I did the DME plug 13 resistance test from Clark's and it passed with about 3 K-ohms... Would it still pass that and be able to have that prob?

Also, I hooked up a new gauge to the fuel rail and it wouldn't register psi until I jumpered the DME relay...then it went to 40 really quick and stayed there. Put the relay back in and I think I can still hear the fuel pump going, but still no start.

It did make a couple more little pops and 'blubs' out of the exhaust, like it thought about starting for a second...I think that was with my foot on the gas.

I guess I should check that the injectors are firing properly? Is it okay to just unbolt the rail and lay it back over the valve cover and firing the injectors on a towel or something?

Thanks guys..

Stephen

Jeff N.

Get a noid light to test the injector signal at the injector clip. With this, you'll be able to confirm the firing signal at the wiring clip. Much safer.

A quick and dirty firing test is to put a screw driver on the injector body and put your ear on the unit as the motor cranks. You should hear a distinct clicking sound at it trips.

To really verify the injectors themselves are working, pull them and take them to an injector shop. They can flow test them to spec.

I wouldn't recommend pulling the rail and cranking. The injectors will pop out and you'll have fuel everywhere...dangerous.

Ziff951

Well....too late...;-). I cranked it a few times with the injectors out and they're definitely spraying. I still have spark and fuel...WTF!!! Needless to say, I'm losing patience with this stupid thing. Thought it would be great getting back into a 951...ahhh....hindsight.....

Dom1

Not sure if you tried new plugs, my car did similiar when plugs were fouled.

Ziff951

Yeah, just switched 'em out after the first round of starting attempts today. I feel like I've gone through everything...four times... gotta be some stupid electrical something....I think I'm over this. Gonna put a cover on it and wheel it into the street for a few months. If I ever figure it out, I'll let everybody know what it was, if it doesn't get 'stolen', in the meantime...;-)..