96 850 turbo no spark, most of the time Topic is solved

greg850r · Post by **greg850r** » 31 Jan 2018, 08:55

Hi guys,

I have a wagon that quit on my son and after several trips to throw known good parts at it (cam sensor, crank sensor, coil, cap & rotor, wires) we finally put it on a trailer and took it home. We pushed it into the shop and before taking it apart tried it. It started and ran fine. We turned it off and was no start after that. Narrowed it down to no spark just like on the road. My next move is to order everything new and replace it all again. It IS a transplant car, the guy who had it before me put a motor in it, so I've looked pretty hard for obvious wiring issues visually and see nothing out of place or loose. It's showing none of the signs of imminent ignition switch failure, but maybe that's a possibility?

Do we have a test for cam and crank sensors on the car? How about the coil assembly? I would rather put a meter on stuff and crank it over for a reading if possible as the old American 'replace stuff till it works' is getting time consuming the second time around. Not to mention waiting for new parts to arrive before I can go for round 2. Oh, and there are no codes, but the up arrow is flashing when I cranked it last.

I'm also looking for ideas. If anyone can point me to a thread I've missed here or elsewhere I'd love to read it.
Thanks as always, you are all my most valuable resource.

Update. Just took Cam,Crank sensors and coil off running car. Still no spark.

Greg

Post by **RickHaleParker** » 31 Jan 2018, 10:30

This should be easy to trouble shoot ... when in a no start condition.

Go to Harbor Freight or a parts store and get a Computer safe automotive logic probe, they look like the old trouble lights but they have two not one connector on the end of the cord. You connect both of the connectors to the battery and use the probe tip to trouble shoot.

Connect to battery and probe for Ignition pluses at the Blue ground wire on the Ignition coil as somebody cranks the engine. Move the probe to the Red +12V and make sure the Coil primary is getting power.

Right next to the Ignition Coil is the Di Power Stage Module.

Solid Blue and Red wires go to the Ignition coil.
Black is Ground.
Yellow/White is +12V.
Blue/Red is the Ignition pluses from the Engine Control Module.

Report finding and we will go from there.

Computer safe Automotive Logic Probe $9.99 at Harbor Freight

WhatAmIDoing · Post by **WhatAmIDoing** » 31 Jan 2018, 10:52

Since my background is electrical and not mechanical, here's my theory: Since you have all new ignition components, and since the failure was sudden with a random instance where it worked again, I would check the grounds on the engine. One is prominently located near the firewall on the passenger side. I believe there's another towards the front bumper and one on the transmission (can someone clarify location?). If the engine is not grounding to the frame, you will get no spark. The grounds may still be connected, but the matting surfaces have corroded and need to be cleaned to ensure good contact.

greg850r · Post by **greg850r** » 31 Jan 2018, 11:32

Thank you. I'll pull, clean and re-attach grounds since I can do that here. I'll get the harbor freight tool next trip into town.

Post by **RickHaleParker** » 31 Jan 2018, 11:50

I'll pull, clean and re-attach grounds since I can do that here.

Could be the edge connector on the ECM. Sometimes pulling, cleaning the edge connector and reseating the ECM does the trick.

Post by **rspi** » 31 Jan 2018, 11:52

No spark with no codes (with fuel) is usually a bad ground or coil. Check the ground from the battery real good as well.

greg850r · Post by **greg850r** » 05 Feb 2018, 15:42

I finally got the tester you show here and Blue and red wires to coil both show solid red when cranking.
I went ahead and started probing around and all 3 wires to the cam sensor show solid green both off, on or while cranking. Same with the red and blue wires on the crank sensor.

RickHaleParker wrote: ↑31 Jan 2018, 10:30 This should be easy to trouble shoot ... when in a no start condition.

Go to Harbor Freight or a parts store and get a Computer safe automotive logic probe, they look like the old trouble lights but they have two not one connector on the end of the cord. You connect both of the connectors to the battery and use the probe tip to trouble shoot.

Connect to battery and probe for Ignition pluses at the Blue ground wire on the Ignition coil as somebody cranks the engine. Move the probe to the Red +12V and make sure the Coil primary is getting power.

Right next to the Ignition Coil is the Di Power Stage Module.
Solid Blue and Red wires go to the Ignition coil.
Black is Ground.
Yellow/White is +12V.
Blue/Red is the Ignition pluses from the Engine Control Module.

Report finding and we will go from there.

Post by **RickHaleParker** » 05 Feb 2018, 16:24

Move on to the Power Stage Module aka IDM. Located right next to the Ignition Coil.

Solid Blue and Red wires go to the Ignition coil.
Black is Ground.
Yellow/White is +12V.
Blue/Red is the Ignition pluses from the Engine Control Module.

greg850r · Post by **greg850r** » 05 Feb 2018, 17:46

I unplugged the plug on the module that feeds the coil. All 3 wires green with ignition off. Ignition on and outer still green but middle one red. Cranking same as ignition on. Do i need to bare the harness and probe them with it plugged in?

Post by **RickHaleParker** » 05 Feb 2018, 20:45

Do I need to bare the harness and probe them with it plugged in?

No, the way you did it is fine .... the probe completes the circuit.

What is #3 doing when cranking?

When cranking, we are looking for, 1. Green, 2 Red 3 Pulsing.

1 -------------------------------
2 -------------------------------
3 ----*----*----*----*----*----*

Make darn sure your not seeing a pulse or flicker before moving on because, the next thing up stream is the Engine Control Module. Things are not so simple upstream.

Depending on the characteristics of the LEDs in the probe. Pulses can manifest in a number of way. Flickering of the Green LED, Red LED comes on weakly. Alternating Red and Green.