Hi Guys,
I picked up a 99 LS with a 3.1 & 100k on it, and it had blown intake gasket. It tore down the engine to the head and it was apparent it was the rubber intake gasket, so I didn't pull the heads. Pulled out about 8 courts oil/coolant batter out of the oil pan, so I pulled the pan and replaced the oil pump as well. I ended up going through the fuel rail, cleaning the injectors and replacing the fuel filter too - cause it's been sitting for a year. This whole thing has been extrememly time consuming and not at all what I expected - very difficult - should have wrote down tear down procedure big time. UGH!!

Long story short, it cranks, but won't start. If I spray ether into to intake, it putters some with a couple clangs, but then nothing. Pressure in the rail seems good, but it almost seems like it's not getting fuel. I pulled a plug and it seems kind of dry. The fuel pump primes for about 2 seconds when I turn the key, but if I crank it with the open link, I'm not seeing any fuel come out-hmm. I could see the CAT getting clogged if that Oil-coolant got into the exhaust ports, but they were clean on the intake. This car has got me stumped! Any help would be greatly appreciated!!! Thanks!

 

Just wanted to post an update and some tips on this job. These forums have really helped greatly. It turned out that the crank sensor wires were burnt from the exhaust, which was stopping the spark from the coil pack. Found an excellent website for testing componenst for stuff like this. Below is a link.

Part 1 -Ignition Module & Crank Sensor Test: GM 3.1L, 3.4L.

I'm going to have to send this guy a "thank you!".

The intake gasket where it meets the upper head seemed to be the issue. It did look apparent on the removal. It was the rubber gasket, and the guy at oreilly's sold me on the metal one and told me to stay away from the Orange coolant. The original owner had the head gasket done at 60k, but the intake nuts I think rattled loose some, because they were only wrist tight. I sent the clean & dry bolts down with some lock-tite on assembly this time. I probably could have gotten away with not pulling the oil pan, which is a whole other job, and you litterly have to drop the entire carriage to get to it, which dissconnects the steering rod. If you end up doing this, make sure have a mechanic there walk you through procedure on both the intake gasket and oil pump/pan. Take pictures and write down disassembly procedure, tag everything, clean your hardware.

Just ran an oil flush and let it run, till it smoothed out. Going to have a pro do a power flush in the coolant. Hopefully she runs good.