1998 Buick Lasabre will not start

I have a 1998 Buick lasabre…65k miles. I was driving one day and it suddenly quit. I couldnt get it to start and I had to rent a trailer to get it home. In trying to diagnose the issue I found it had weak spark. I replaced the ICM…still weak spark. Then I had it hydrolock on me. I odered coils. Then for fun I took the ICM off and had it tested…it was bad. Put another new one on…still nothing. Changed the plugs and wires…it started. I needed new ball joints and front brakes and did those the next day. Then when I tried to start it the starter broke…the housing snapped presumably from the hydrolocking. Replaced the starter…then it wont start again. Then I replaced the crank sensor. Still nothing…just replaced the PCM last night…still nothing. I am at my wits end! I am going to have the ICM checked again tonight …

Are you doing this work yourself? If you are, I’d suggest getting good professional help. You are just shotgunning the fix by throwing parts at the car, not diagnosing the problem. If you are paying a shop to do this, stop. Find a better mechanic and tow it there.

If you hydrolocked the car and continued to crank it, don’t be surprised if it is now destroyed.

If you are working on it, remove all the plugs, pull the fuel injection fuse or disconnect all the fuel injectors. Crank the engine to clear the fuel out of the cylinders. If the engine binds up when you do this, the engine is done for. If it clears the fuel and spins OK, install the only the plugs and hook up the spark plug wires. Spray starter fluid into the engine. If it starts, you have a fuel problem not an ignition problem. If it doesn’t start you have an igniton problem AND a fuel problem.

Post back with what you find and well take a step further.

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Yes i am doing the work myself. I have been in a perpetual argument for weeks with the wife about taking it to a shop. And I did clear the motor each time it hydrolocked on me. It is cranking over just fine, just spark is too weak to do more than sputter. I have compression tested each cylinder and also pressure tested the fuel. Both tests came out great.

And I did the proper relearn sequence for the computer as well.

define “hydrolocking” and why your car is doing this repeatedly.

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a cylinder filled with fluid causing the engine to lock up. This happened to be fuel. I believe it is from the repeated cranking trying to start the damn thing

OK, so you fixed the problems since you posted this…

So now it is running OK? Why would it not run once you replaced the starter? It cranks but won’t run now? Are you sure you hooked up all the wires… specifically the engine ground.

Still missing some info…what engine? 3800 V6? Non-supercharged? And how many miles on the engine? Is there a check engine light showing? When you did a scan, could the device communicate with the ECU?

Run the test I suggested. You need to determine if this is a fuel problem, spark problem, or computer problem.

It still does not start, it rolls over fine. 3800 v6 non supercharged. No check engine light or codes. Code reader scans computer fine. I have tried starting fluid still does not start. As stated I have checked fuel pressure with fuel pressure gage…its good. Checking spark it is weak again after the starter replacement. When it started the day before the starter replacement I only ran it a few minutes. The next day when I went to start it the starter was grinding.

Sounds like one of the fuel injectors is leaking or spraying continuously, flooding the engine and filling one of the cylinders with fuel. Inspect the injector wiring for damage/short to ground.

Is it always the same cylinder that is filled with fuel?

It happen twice, once was cylinder 5 the other was 2

I don’t think you really discovered yet what caused it to stall in the first place. Could it be a timing problem since you replaced everything else or could it be faulty parts of workmanship of the parts you already replaced? Focus on spark?

When mine stalled one morning on the freeway, I had no codes. Swapped computers and no luck. Had it towed and it took the guys about an hour to discover a cracked crank sensor in addition to a wobbly balancer (common problem). I was on my way again in early afternoon $500 lighter, but fixed. Just sayin’.

I am going to take the ICM in again tonight to have it tested since I had the first one I bought was bad out of the box

For my 3800 I had a junkyard known good coil and attached module that could be swapped out as a test. Cost me $25. Nice for ruling things out.

I just read some reviews on the ICM I bought (Duralast brand, $160) and they are known to have problems. If I have spent a few hundred dollars chasing a bad ICM I am gonna be pissed! Nut I have replaces all the coils. The spark is weak…it don’t get that nice crisp pop you typically get.

I had a 1998 olds intrigue that kept losing the battery ground to the fender. The cable from the battery is only a little more than a foot ling and grounded right under the battery through a 10 mm bolt into the fender. The car would stall at highway speed, I could restart it by putting it in neutral and not losing more than 5 mph.

I fixed it by adding a second ground cable under the 10 mm bolt to the engine block.

I don’t think it’s a bad ground I used jumper cables to add 2 additional grounds and it didn’t help

If it is corrosion at the rediculous side terminal battery connection that gm uses, the jumper cables won’t help.

The engine should never hydro-lock because of weak spark, the fuel mist will be pumped out of the cylinder on the exhaust stroke.

Broken starters indicate a serious hydro-lock problem. A more appealing spark is not the solution.


If there is so much fuel getting into the engine that it is truly causing the engine to hydro-lock then I would have to think the fuel pressure regulator has failed badly. I would also make sure that the valve timing doesn’t have an issue. When engines suddenly die while driving it is usually due to a timing belt problem. You should also check your compression.

this. and ya gotta wonder what else is bent/broken with this reoccurring hydrolock issue…