Mysterious Loss of Power

socalfiver · Post by **socalfiver** » Mon May 02, 2011 2:10 am

I drove my car over 1000 miles this week. From Los Angeles to Las Vgeas, and about 70 miles every day in town, then back to Los Angeles.

Unfortunately, my car lost power 16 miles from home. I was cruising along at 75, then the engine lost all power. The tach needle jumped and then dropped to zero. It does not move when I try to restart.

Any ideas where I should start looking? I had her towed home (Thanks, AAA!), and will look at in the AM.

GripGreg · Post by **GripGreg** » Mon May 02, 2011 3:30 am

Well, at least you have the right calling card! Some of these guys don't belong to triple A! I know! Go figure!
Lemme know when & where you find that loose wire so I can tighten mine. It reminds me of that commercial. How many people were with you?
Now I know why you didn't make the Malibu run.

Good luck,,,,Greg
Ps What area do you live in??

socalfiver · Post by **socalfiver** » Mon May 02, 2011 9:20 am

I was by myself.

I live in Eagle Rock, just NE of downtown Los Angeles.

Pete K · Post by **Pete K** » Mon May 02, 2011 1:18 pm

I'm sure it won't be too hard to track down. All they need is fuel, spark and air

wmmag · Post by **wmmag** » Mon May 02, 2011 1:34 pm

Is an alarm wired into the car? I was experiencing random episodes of my car dying. Not fun, especially on the freeway. What was happening was an old* alarm that I never used would come alive on its own and kill the engine. Perhaps that's what's happening to you.

--Bill

*How old? So old that it's armed via a key into a lock installed on the front fender.

Mike W. · Post by **Mike W.** » Mon May 02, 2011 9:25 pm

The tach needle jumped and then dropped to zero.

That suggests it's ignition related. Check for spark and go from there.

socalfiver · Post by **socalfiver** » Tue May 03, 2011 12:11 am

When I attempt to start it, I'm only getting 1 weak spark out of the coil wire instead of repeated blue sparks.

Each time I crank it over, I get just one weak orange spark then nothing.

socalfiver · Post by **socalfiver** » Tue May 03, 2011 11:30 am

It turns out that my combo relay wasn't activating. I swapped it with a known good one, still nothing. I swapped out the ECU, and the combo relay is now working as expected (clicks on when key is turned to on position, and activates the fuel pump when the afm door is opened).

The tach needle still does not move when attempting to start.

I swapped out the ICM, and still no increase in spark. Just a single orange spark.

Could the coil be shot? Is there a way to rule it out?

Could a faulty tach be at fault? (this happened with my FIAT).

Bill- there is no alarm, all the wiring is stock.

socalfiver · Post by **socalfiver** » Thu May 05, 2011 8:24 pm

I have 3 ICMs in all. when I use 2 of them, the tach needle does not move when I attempt to start.

The third one makes the tach needle move when I attempt to start.

Which is correct?

Also, the impulse trigger wire is brittle and I suspect may be shorting out. Is it possible to swap in a new wire? Where does one find the shielded wire that was originally used?

Lenny D. · Post by **Lenny D.** » Thu May 05, 2011 9:33 pm

You need No. 8 in this group.

socalfiver · Post by **socalfiver** » Thu May 05, 2011 11:14 pm

I've got a spare distributor. I'll try swapping that in and see if she fires up.

socalfiver · Post by **socalfiver** » Fri May 06, 2011 11:02 am

I'm one step closer.

Swapping out the distributor has gotten the car to sputter and cough, but it still won't start. Now I must be getting spark (hard to check without an assistant!). Thanks, Lenny!

Since I eyeballed the timing during the distributor swap, it's probably just off enough to not start.

Is there a way to verify TDC on cyl#1 without removing the valve cover? Since it's opposite #6, I'm guessing that if I set the crank to tdc, #6's lobes will be pointing up. is that correct?

I'd still like to replace the impulse trigger wire. Am I correct in assuming it's not available? I can only find it as part of the NLA engine wiring harness.

Lenny D. · Post by **Lenny D.** » Sat May 07, 2011 1:59 am

On aircooled VWs finding true TDC on any cyl. was to put a pencil into the spark plug hole and watch as you turned the engine by hand to see where the piston stopped moving the pencil out of the hole and started back in again. Fine tuning by rolling back and forth gets the exact spot (irrespective of what markings are on pulleys). I don't see why you couldn't do that here.

If the harness is NLA then you have to chop, and splice a length of wire (soldered) to replace the defective one to the impulse sender. It has to be right, this is your ignition starting point.

socalfiver · Post by **socalfiver** » Sat May 07, 2011 9:39 am

I can hit true tdc on cyl 1 by matching the timing marks on the crank pulley, but that mark is either tdc on cyl 1 or 180 degrees out (tdc on cyl 6).

I guess i should stop being lazy and remove the valve cover to ensure I'm at tdc on the correct cylinder.

As far as the wire, the original is a shielded wire and has a specially formed plug end that can't be disassembled. I'm trying to track down similar style shielded wire, and will most likely sub 2 tiny plugs for the original plug end.

I'm visiting several salvage yards today to hopefully find a donor vehicle with a pickup wire that's less brittle and cracked than mine.

socalfiver · Post by **socalfiver** » Mon May 09, 2011 12:09 pm

All fixed.

Traced the problem to a brittle impulse trigger wire. It had cracked and shorted internally. Depending on the position of the wire, it would sometimes allow the engine to sputter.

I've temporarily replaced the wire with a heavy duty shielded wire from a set of RCA cables. I'm looking for a shielded wire that can endure some engine bay heat.