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Discussion Starter · #1 ·
Hey guys, so I've been spending the last month or so meticulously changing the engine in my N/A SAAB 900s. To the extent that every single connection I labeled so I know exactly where everything connects. At least best I could, some of the connections on the alternator/starter seemed a bit tricky but Im fairly sure they are all correct.

Anyway, I finished tightening down the last ground and went to fire it up. Crankcrankcrankcrankcrank......crankcrankcrank. Engine is not getting fuel, or spark. The old engine ran perfectly (it was unfortunately attached to a bad transmission) so I'm fairly certain everything in the car is OK, and the new engine is exactly the same year 2.0 jetronic ezk yada yada so I don't think there's an incompatibility problem.

The junkyard I bought it from said it was running perfectly when they pulled it out of the car, and the owner had even driven it himself. Where do I begin? Why does my life suck this hard? Is there some *DUH* thing somewhere that tells the ecu its OK to start the engine? Im stumped.
 

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Double check all the connectors to be sure you have not had a wire terminal push into a connector instead of into it's mate. It can look "connected" from the outside, but not actually provide the needed continuity. If all connection are good, follow the standard trouble shooting operation for a no start.
 

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Discussion Starter · #3 ·
Double check all the connectors to be sure you have not had a wire terminal push into a connector instead of into it's mate. It can look "connected" from the outside, but not actually provide the needed continuity. If all connection are good, follow the standard trouble shooting operation for a no start.
thanka, i looked over the connectors, and the idle air control valve was as you described. the terminal pushed out of the connector, however no dice when i got it plugged in. I guess I'll buy a voltmeter..
 

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Sounds like the crank pulse is missing.............
How is the crank pulse sourced on the engine?
Distributor or crank sensor?
If original, the crank sensor would a high suspect from what I read in your post.......
 

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Discussion Starter · #5 · (Edited)
OK multimeter got, can I check the voltage output of the CPS? I have a feeling it is OK because the tach is bouncing. What other signals will cause the ecu to stop the fuel pump and ignition? There are only so many possibilities aren't there? Car has power, starter engages fine, dash illuminates, radiator fan works...also the "new" engine supposedly only has around 70k mi on it.
 

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What do you mean by no spark? Are you grounding the wire coming from the coil to see if there is spark or did you remove a spark plug, plug it into the wire and ground it? I would start at the coil and make sure it is working, because if it is not well then how will the spark get to the cylinder. If the coil is not working then it could be the coil itself or wiring problem. If that is working then you can go to the distributor and see what is going on there. What's also nice, if you have the spark plug out and the engine is turning over you can feel if it's getting compression. Doesn't mean it's with in spec because you would have to put a guage on for that. Although that's not a bad idea to do since you don't know about this engine. Next, what I would do is jump the pump, there is a fuse in the engine compartment but if you have the time, maybe you can get to the relay under the dash, assuming yours is like mine. If the pump comes on then you know it is working. Next, check the voltage at the injector connector. You should see 12v. if you see low voltage, check the ground right on top there by the injectors, make sure that sucker is bolted down tight and free of any corrosion.
 

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Just because junkyard said it is perfect, do not mean it is. Do a compression check, verify timing.

Once that is established, I think pin 1 on ECU is the crank signal. You could check for pulse there while engine is turning.
 

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OK multimeter got, can I check the voltage output of the CPS? I have a feeling it is OK because the tach is bouncing. What other signals will cause the ecu to stop the fuel pump and ignition? There are only so many possibilities aren't there? Car has power, starter engages fine, dash illuminates, radiator fan works...also the "new" engine supposedly only has around 70k mi on it.
If you jump the fuel pump at the fuse block (from #27 to #30) you'll eliminate the ecu fuel circuit. If the car then starts you know the ignition side is good and can start chasing a fuel circuit problem.
 

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Everything is plugged in, right?

Try compression check, if it low, dump some oil in the cylinders and try to start it, sometimes old engine can lose compression if cylinder gets "washed" and oil will get it running again.
 

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Discussion Starter · #10 ·
I haven't completely verified the timing, but I rotated the wires all around the 4 possible positions on the distributor and no go on any of them. I went to the book to start checking the ignition system and the 2nd check it gives is to test power to the EZK. Put the voltmeter on the pins in the connector as per the instructions and nothing, should be getting battery power but instead I get a blown main ignition fuse. Somethings totally ****ed, I give up. I'm dragging it to Independent Automotive, a great SAAB indy in Crystal Lake, IL. I can't wait for him to scold me on how terrible this hunk is. *sigh* fml
 

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Before you throw in the towel....

I haven't completely verified the timing, but I rotated the wires all around the 4 possible positions on the distributor and no go on any of them. I went to the book to start checking the ignition system and the 2nd check it gives is to test power to the EZK. Put the voltmeter on the pins in the connector as per the instructions and nothing, should be getting battery power but instead I get a blown main ignition fuse. Somethings totally ****ed, I give up. I'm dragging it to Independent Automotive, a great SAAB indy in Crystal Lake, IL. I can't wait for him to scold me on how terrible this hunk is. *sigh* fml

  1. Is the fuse already blown, or does it blow as soon as you try to activate the circuit? If the former, install a new fuse of the correct amperage and retest.
  2. If the latter check and see what circuit (including all splices/branch off points) it fuses. Then trace the wire, it is not unheard of to pinch a wire when R&Ring large components. If so repair and retest.
  3. For fuel (now this depends on how/when the fuel pump is commanded on). If proper ignition/RPM signal is required, see above + other RPM signal related diag. If however, the fuel pump comes on (though usually only for a few seconds) in the KOEO (Key On Engine Off) position, then check that power is available at the pump at the proper time. (A test light is recommended. This is because a DMM will display 12V even if there is low amperage. You'll think you're all good when you see 12V, but there could be high resistance. If you use a test light on a circuit and it glows dimly then that would indicate high resistance, correct and retest. I'm a Ford tech, and I always use a test light when diag.ing fuel pumps. Though always test the test light itself across the battery, just so you aren't chasing a ghost problem.) Once you've confirmed power at the pump listen closely and ensure that it actually comes on.
  4. Plus, sort of a "while you're at it" type thing is, use a test light to check all the fuses. As well as all the circuits that are supposed to have power in KOEO and KOER.
  5. Check you're grounds and alternator connections.
Hope I'm not repeating any advise, I only read the first few posts, scrolled down, saw you were gonna give up, and figured I'd better at least say something.



Also I currently have the entire powertrain out of my '88 SPG, and I was meticulous to label EVERYTHING just like you, so this really scares me. Let me know how it turns out, including the cause.
 

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Discussion Starter · #12 ·
Thanks for all your help guys, I have learned a TON about proper engine diagnostics in the last month or so! I ended up tracing the problem back to the Crank Angle Sensor, I know I know, I always secretly suspected it too. The yard said it was a running engine, lesson learned don't trust anyone! I swapped the sensor off my old engine into the new one and she fired right up.

I waited so long to do it because everyone has been telling me how horrible it is a job to do, but I surprisingly had no trouble, and did the entire job for the first time in about an hour. I think it helps that its a non turbo, and I can sit on top of the engine with my legs in the engine bay and work with my head resting on the windshield. So thanks again, I need a saabcentral sticker for this thing!

PS. It seems every old SAAB engine I've ever heard start cold has a loud ticking that goes completely away as it warms up. Is this ordinary?
 

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Thanks for all your help guys, I have learned a TON about proper engine diagnostics in the last month or so! I ended up tracing the problem back to the Crank Angle Sensor, I know I know, I always secretly suspected it too. The yard said it was a running engine, lesson learned don't trust anyone! I swapped the sensor off my old engine into the new one and she fired right up.

PS. It seems every old SAAB engine I've ever heard start cold has a loud ticking that goes completely away as it warms up. Is this ordinary?
Good Job!

The ticking is most likely the hydraulic lifters, and yes, for a cold start or a few days in between stars, some ticking is ok. Put half a quart of Marvel Mystery oil in the next time you change oil. If that doesn't "cure" it, then do a pint of STP oil treatment or similar after that oil change
 

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PS. It seems every old SAAB engine I've ever heard start cold has a loud ticking that goes completely away as it warms up. Is this ordinary?
Hydraulic lifters. They nearly all do it, even from new. Should go away as the engine warms up.
 
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