Cascade Crew

[85 T/A WS6]

The lil 91 Sunbird vert bit the dust last week and Im baffled. It wont start but cranks over. It has spark and the fuel pump is working (makes noise, no valve to test though)

I changed the fule filter and the wife replaced the fuel pump relay.

I opened up the TB and sprayed start fluid inside and nothing. This leads to to think the timing belt busted (do they break or just strip out?)

The wife thinks its the crankshaft sensor (it has distribtorless ignition)

BAd month for the ponchos, MY T/A died while pulling into the muscle car meet and had to tow it home.

[chevymad]

If it has spark then the crank sensor is good. Can you check compression? This would tell you if the belt is broke or stripped. Does it sound normal cranking? I can usually tell just by the sound, if the belts gone it spins too easily. When you pull the plugs to check compression see if they're wet or not. If they're wet the starting fluid won't make any difference. If it has spark, dry plugs, and compression yet won't fire on starting fluid, you may have a plugged exhaust. Remove the O2 sensor and just let it hang. See if it fires up then. The O2 hole will allow the exhaust to escape.

If the plugs are wet, it's probably a sensor issue. Most likely coolant sensor..

[85 T/A WS6]

Can you check compression?
I can get a gauge and see.

Does it sound normal cranking?

Yes.

#3 plug seems oil fouled, spark is erratic. Engine has 90k on it.

Thanks!

~Don

[blue89]

Sounds to me like its the ignition module. $250 for that piece. I would ohm out the coil packs and crank position sensor. If those three are good, then I would get a new module.

I had a non-running corsica that I bought so I know a little bit about these 4 banger motors (if they have the same one).

[85 T/A WS6]

Thanks, The module is by the coil pack under the intake manifold, I may be able to get to from underneath.

Can a plug spark with enough voltage to see the spark but not enough to ignite?

I have a haynes, really need a chilton

The haynes says ohm the crank sens from the ECM harness, I cant even get a probe in there

[blue89]

yup, you can "reach" everything from under the car. There are two coil packs that have two 7mm screws each (i think). You'll need a 1/4" driver with a deep socket. Those screws also hold bolt the ignition module (IM) down. So once you unbolt the coil packs, the IM falls off. The crank position sensor (CPS) is directly under the IM and may require a cresent wrench. So just take everything apart and out and check it on the bench.

There are two harnesses in this entire system. The first one connects the ECM with the IM, the second goes from the IM to the CPS. The coil packs are waste spark and electrically connect to the IM when they are bolted in place. Being waste spark, there are two spark plug wires per each. It shouldn't matter which plug goes to what, as long as they are banked correctly (but reconnect as recommended). I believe 1-4 and 2-3 are banked, but its been a while.

You won't be able to see anything with your hands up there, but its not too bad. Since you have everything out, it may be worth it to replace the crank position sensor since its so hard to get.

Thats almost everything I know about that.

[85 T/A WS6]

Thanks again. I towed it in to the shop, it was the timing belt. Well over $500 to fix as they recommend replacing the water pump at the same time.

ouch