formula137292

So the story starts like this:

I'm driving and everything is fine. I stop at a traffic light, when the light turns green I put it in 1st and the car spits, spits, sputters and dies right in the intersection. I push it to the side and try to start it again and nothing...the engine turns and turns and doesn't even sound as if it wants to start. I fold and get it towed back to my place.

Here's where it gets weird. I don't touch it for two days. After two days, i decide to give it a shot and try starting it. After turning for a couple seconds, it starts right up. I let it run for 30 minutes. All seems good. I think, wow, scary, I'd rather it not start so I can hunt for a problem. My wish came true...

Next day, I go out to start the old girl and the engine turns about a one or two seconds before hearing a metallic clanking when turning. I stop quickly and think, crap, that is NOT good.

So I begin my research to try and figure out what could have happened. After some reading, I think that, given there is 117000 miles on the car, a good thing to check would be the timing chain. Maybe the chain was jumping time. I was convinced. Stretched chain, jumping sprocket teeth = loud noise AND engine out of time = engine dieing in the intersection

Turns out, now I'm scratching my head because I checked out the timing chain and there's a little slack (about an inch) but the timing marks are still aligned on the crank and cam sprockets. Could this slack still cause an engine to die like I described? I thought of checking out the starter but the starter was turning the engine fine when I tried starting the engine after it had died. I'm lost. Anyone have a similar problem or have any ideas?

(Oh yeah, I also replaced the fuel pump, plugs, plug wires, alternator, MAF, air duct, and battery recently. Also, before the engine died, I had been getting a persistent PO171 and PO174 DTC (Lean on Bank 1&2) I couldn't figure out what this was caused by except for....I noticed these DTCs popping up when I replaced the MAF and air duct with a Moroso cold air intake.)

Any help would be greatly appreciated.

justin455

I'm an LS1 guy and given what you've replaced and the codes I would say ignition coil...so I'm gonna say it might be your optispark.

formula137292

Justin,

I bet you were right. While I was replacing the timing chain and elbow deep in the LT1, I replaced the opti cap and rotor as well as the coil. Inside the opti where the optical sensor is and disc, there was oil. Luckily the oil wasn't on the disc so I just wiped the inside clean being careful not to touch the sensor or disc. A seal must have been leaking. I replaced the distributor seal, water pump drive seal, crank seal and cover seal. The car runs now so I hope the problem is solved. We'll see.

justin455

Good luck, I know everyone rags on the opti, but you got a lot of miles from it no problem. Once they get wet (or oiled in this case) it's most likely f*ed.