No start, no spark

[JPaganel]

Our 2007 2WD Vue 2.2L refused to start one day.

Checked all fuses - all good
Swapped relays
Checked for gas at fuel rail Schrader valve - have gas
Checked spark - no spark

Replaced crank sensor
Replaced ignition module

Checked ignition module connector - have ground and 12V when ignition is on

I kind of thought that both coils going bad is unlikely. I could check them, but don't know what resistance they should have.

Any other ideas on what I might be looking at?

[waiter21]

Crank position sensor - located under the oil filter.

[fdryer]

JPaganel, is Passlock/security indicator off or flashing during starting? Describe how you checked for spark. Does fuel spray from the fuel test valve when the valve stem is depressed after turning ignition on?

[JPaganel]

Originally Posted by waiter21

Crank position sensor - located under the oil filter.

First thing I replaced. No joy.

Originally Posted by fdryer

JPaganel, is Passlock/security indicator off or flashing during starting?

It comes on solid for the first few seconds with the rest of the dash lights, then goes out with most of them if I continue cranking.

Originally Posted by fdryer

Describe how you checked for spark.

With a bulb-type spark tester

Originally Posted by fdryer

Does fuel spray from the fuel test valve when the valve stem is depressed after turning ignition on?

Yes

[fdryer]

Ok, your answers seem to point to lack of spark. I forgot to ask - removing spark plugs should reveal wet plugs as indication of a good crank sensor and engine computer operating injectors to spray fuel into each cylinder while controlling the ignition system for spark. A dead crank sensor won't allow the engine computer to run at all - no spark, no injector pulses, no fuel pump operation while starting and driving, a dead EFI system. Checking for fuel on plugs verifies 99%of the EFI system is operating. Loss of ignition/spark points to the ignition control module, coil pack and wiring.

[JPaganel]

Originally Posted by fdryer

Ok, your answers seem to point to lack of spark. I forgot to ask - removing spark plugs should reveal wet plugs as indication of a good crank sensor and engine computer operating injectors to spray fuel into each cylinder while controlling the ignition system for spark. A dead crank sensor won't allow the engine computer to run at all - no spark, no injector pulses, no fuel pump operation while starting and driving, a dead EFI system. Checking for fuel on plugs verifies 99%of the EFI system is operating. Loss of ignition/spark points to the ignition control module, coil pack and wiring.

Haven't pulled the plugs. Will try that.

I should also point out that I have hooked up a code reader to the OBD port, and the ECM is communicating. It doesn't show anything useful, since the engine isn't running, but it does come online and respond, so I don't think it's dead.

The crank sensor is brand new. I suppose it isn't impossible that I got a bad one, but I've never had that happen before.

How does the ECM connect to the coil packs? Is there a connector to test?

[fdryer]

If you didn't throw away the original crank sensor, you can measure it for resistance with a multimeter. In general, crank sensors will have between 700-1200 ohms. Only two wires will have resistance. A third wire is for shielding the low voltage signals and will not provide any resistance when measuring against one of the two wires. Resistance for good sensors will not vary at ambient temperature, freezing, hot or after rapping it against a table edge. Historical records from many members here in each forum has show intermittent/varying resistance or complete failure (open circuit) in one or several states. Mine changed resistance as engine heat affected it - it failed while driving, became operational after engine cool down and then failed as engine heat forced it fail, the engine dying each time.

Intermittent crank sensors can be tested on a bench by measuring resistance after each test; ambient temps, immersed in boiling water and after rapping it against a table edge several times. Each test replicates the engine environment. Good sensors won't vary resistance by much.

OBD II readers are only as good as the design parameters. It will decode emissions errors with better readers decoding abs codes. General purpose readers will not tell you if an engine computer is faulty except by interpolation - zero communication that may be a blown fuse, damage to wiring between computer and reader or computer failure. Advanced knowledge of electronics helps to determine whether or not engine computers fail. As a rule, engine computers rarely fail.

[DrewsBrews]

Also there is a small ground terminal on the engine a little higher up the engine above the crank sensor that goes back into the loom. The wire can corrode enough to be "connected" to the terminal but not have reliable conductivity.

For me it would cause random total loss of ignition. Fix was crimping on a new ring terminal and reinstall.

[JPaganel]

So, life interfered, and I haven't got back to fixing this thing until just now.

But, I have a new development.

I found a troubleshooting guide and a schematic that told me the pinout of he connector that plugs in to the ignition module.

The brown/white wire is from the crank sensor and the black/white is ground.

Ground tests fine - there is minor resistance to the block. The sensor wire, though, is open. So, I started unwrapping the harness and tracing it. Found a different broken wire - the orange one. It should be the control signal from ignition. Spliced it, but still no joy.

Pulled the starter and found that the crank sensor connector has holes too small to fit a probe into. Wires to the plug seem OK, so more unwrapping might be in order.

Meanwhile, the starter terminal fell off while I was unscrewing it. So, I'm in for a new starter.

Any ideas how I can get at the sensor contacts to test continuity? Or a common point of failure?

[fdryer]

Did you check for fuel in each cylinder? Repeated starting attempts should flood a cold engine with fuel. Remove plugs and examine them for wetness or smell of fuel to verify injectors are operating. One injector fuse powers all injectors, labeled as IGN/INJ 15A.

If I'm not mistaken, all 2.2L engines share the same EFI system configuration. I included a copy of ignition wiring, crank sensor and description of the EFI system from '05 service manuals.

[JPaganel]

fdryer, the schematic you posted is the one I used.

BN/WH wire marked CMP Sensor Signal is the one that is open.

OG wire marked IC Timing Control is the one I found broken.

[fdryer]

Hmm, what's the general condition of wiring? You may be describing either severely damaged, weathering or strained/stretched wiring. Crash damage?

CMP is defined as cam position without a sensor. It's electronically derived based on crank sensor and electronically controlled ignition timing. Sort of a feedback signal from the icm to the ecm. All you can do is repair damage found and hope for the best.

[RobertGary1]

Are you getting fuel pressure at the rail? Does it catch if you spray quick start in the TB?

-Robert

[JPaganel]

I win. It started.

I fixed the broken wire, and then removed the wire loom and traced the wire that on the schematic says is coming from the crank sensor and had no signal. It doesn't actually come from the sensor directly, it come out of the ECM mounted on the passenger side of the engine.

I bought a used ECM on eBay for $40, plugged it in, replaced the starter, and it fired up. Service number 12202143, other number 12614702.

It is a little hard to start - sometimes it will catch, rev up to 1000, and then stall, but after a few tries it will start and run. I'm not sure if that's a function of old gas (that tankful is at least a year old), or there is something else going on. The Check Engine is lit, I need to find my scanner to read it.

One way or another, it's more alive than dead now.

[fdryer]

Originally Posted by JPaganel

I win. It started........One way or another, it's more alive than dead now.