97 LeSabre won't start after fixing coolant in cylinder problem

Hello,

1997 Buick LeSabre
156,665 miles
3.8 VIN L engine
(wife's car)

Awhile back she had the A/C serviced. A few days later, while driving along, she could not get the car to go over 30 MPH. (she does not know if the car was overheating.) She stopped for gas and when she went to restart, the car would not turn over. I suspected dead battery, but an overnight charge would not crank the engine. The engine would do nothing, not even a partial revolution. (I checked radiator while doing this, and needed to add at least 3 qts. water)

I had the shop look at it and was told that the engine oil level was too high (it's at about 7 qts.), and that something must have broken loose in the engine, and the car needed a new engine.

I brought the car home and pulled the plugs, and the engine cranked just fine, though shot anti-freeze out of the #6 cylinder. I was told by a gentleman who had the exact same problem that the problem was the upper intake manifold (design problem. Past posts have discussed this issue)

I replaced the upper intake, gapped plugs and now the engine acts like it wants to start, but not really. If I open the throttle while cranking, it sounds like it wants to backfire.

I have checked all plugs, and they fire just fine. I have checked the cam gears and chain, and the cam timing is fine. Scanning ECM indicates no problems.

One note: When I started putting the engine back together, I was really tired and put the positive cable on the negative terminal, and when I went to put the negative cable on, sparks flew. I did this twice before I figured out my mistake. The ECM does not appear to be fried, though, as a pocket scanner does not indicate any problems.

Any ideas what is going on? Could my mixing up the battery cables have caused an additional problem?

Any help would be appreciated.

_________________
Robert Hamilton

I would start by checking all the fuses under the hood, driver side and passenger side fuse/relay center. Check fuel pressure next. If you have fire, and the engine is turning over at a good pace with injectors firing, it should start if you have adequate fuel pressure.

BTW, hooking up the battery cables backwards is about the worst thing that could happen to the PCM and other electronics devices.

What may have happened is when the #6 cylinder filled with coolant, you hydrolocked the engine. This can do catastrophic damage including bending the connecting rod and/or breaking a piston. I would do a compresssion test, to see if you have low compression in cyl 6.

I had the same problem about the same time you posted this. I had spark and fuel, but it would not start. I changed plugs again (2nd new set) and it started right up.


Might be a little late
HTH

I just recently had to replace the upper intake manifold on my 97 Buick Lesabre due to the coolant passages leaking into the intake and cylinders and Hydro-Locking the engine up, and I had the same trouble with it not wanting to start after the repair. What I did was to first bleed the air out of the fuel rail by turning the ignition switch to on or run position and then depressing the Air Bleed Valve on the Front Fuel Rail Line (looks like a Tire Valve Stem). Use some rags around the valve and be careful cause it will spray when purging! Then I removed all six spark plugs and cranked the engine over to purge the cylinders of all residual Anti Freeze that may be remaining in the cylinders. Completely clean and dry all spark plugs before re-inserting them. Reconnect all plug wires and then crank the engine over. It may sputter for a little bit until the cylinders get primed, but just keep cranking it untill it starts firing. At least this is what it took to get mine started. GOOD LUCK!