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Discussion Starter #1
Hey all!

Got a bit of a thing and I'm rather confused at the moment. here's what happened.

Last night coming home i hit a rather nasty pothole and the car went dead. After investigating, i found that the APC fuse (#24) had blown. Replaced it and still no-go.

I pulled the DI cassette and it seems i'm not getting spark. Granted the engine was hot, but it seeems like there's no fuel spray either, as I don't even smell gas in the cylinder.

I can only think of 2 things that would take out both of these at once - the CPS, and the ECU. CPS doesnt' seem like it'd be that susceptible to vibration. The ECU's solid state-granted, and fairly robust, but do you think a nasty shock like that could have blown it?


Thanks in advance. i'm stumped.

I've checked all other fuses, gauges work, fuel pump powers on, all other systems have power. No relays came unseated . Couldn't find any loose wiring connectors. My main suspect is the ECU. Hope to hear some opinions..


thanks again!
 

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Check the ground from the transmission to the frame, on the driver's side of the car.

I had a persistent no-start and replaced fuses and the starter....at the suggestion of a tech, I checked this ground, discovered that it was barely attached and the contact point was corroded.

I spent 30 seconds with an emery board, tightened the screw and the car started.

An expensive lesson.. ;)
 

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If you have no fuel and no spark I would take a look at the crank position sensor. They are known to be delicate and when they go both spark and injectors will stop firing.

Cheers,

Steven
 

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Discussion Starter #4
I'm fairly certain that ground is solid. I'll double check it though.

As for the CPS, any visual way to tell its state? If not, do you know the voltage specs for it by chance?
 

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I believe that you can test it by using an ohmmeter to read the internal resistance. IIRC dfor some cars its 550 ohms (-/+ 50 ohms) and 750 (-+50 omhs) on later cars. I would do a search for CPS testing on here and there should specs there.
 

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If you think that you have a bad ground, use a single jumper cable from the negative battery terminal to a good metal location on the engine... Ron
 

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Discussion Starter #7
I have. Power to everything... it doesnt seem like a ground issue. Pothole hit the passenger side... for what difference that makes. I do.t like the fact that the fuse was ;ol;blown though.
 

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Discussion Starter #8
just checked the CPS leads. Across two wires i got continuity and 0.5 ohms resistance. doesn't seem right. No reading off any other combination of leads. also, when cranking, the TACh doesn't budge. I'm still confused as to how the APC fuse would fit into this picture though?
 

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unplug the bpc and try it. I've seen a shorted bpc cause a no start before, and it took me all day to find it. Especially suspect in light of the blown apc fuse. Does the fuse continue to blow?
 

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Discussion Starter #10
no, fuse doesn't blow. BPC has been unplugged for a while as it had died anyway. :/
 

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I would say that the APC fuse may just be a coincidence. The tach not moving on cranking is a classic sign of a dead CPS. Just as a safety measure. The 0.5 ohms was that and not 0.5 kilo ohms? Sorry if I sound like I'm not trusting you it's just I've made that mistake before with an auto ranging ohmmeter.

S-
 

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Get a hold of another ecu. Try that
I used to have an old classic 900 went thru 3 ecu's before I coughed up the money for a proper reco unit
 

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The ECU is right at the passenger footwell, so maybe the harness connector jarred loose...
 

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For a T5 500 ohms is about right for the CPS. If you got .5 I would bet you were on a higher scale and it was actually 500.

Do you hear the fuel pump kick on when you first turn the key on w/o trying to crank it over?
 

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Discussion Starter #15
i've already checked the ECu, took it apart to see if anything was visually wrong (burnt resistor or soemthing) visually it was fine. Connector is impossible to 'jar' loose due to the style, but i've reseated that as well. I'll double check that my ohmmeter didn't swap over to kilo ...

Yes, fuel pump powers on.
 

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i've already checked the ECu, took it apart to see if anything was visually wrong (burnt resistor or soemthing) visually it was fine. Connector is impossible to 'jar' loose due to the style, but i've reseated that as well. I'll double check that my ohmmeter didn't swap over to kilo ...

Yes, fuel pump powers on.

Yes, I've taken the ECU and wiring harness apart many times. If the retractable slide isn;t clamped down correctly, or if it was improperly seated to begin with, it can separate enough to cause problems.

But it sounds like you have other issues.
 

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Discussion Starter #17
No indication o$ being kilo ohms. I'm getting 0.3ohm across the yellow/ground wires.
 
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