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Gas, Spark or O2?


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1990 Coupe.
I have 2 problems that may or may not be related.
When we were changing the harmonic balancer, we had to take off the timing chain cover to get the sheared pin out. Ever since, the car runs horribly. It feels labored and has to run some pretty high RPM to just get moving. Now it won't even start. Here are the facts . . .
It smells like it's getting gas. After turning it over for 4 or 5 minutes you can smell it.
I hear the fuel pump running.
I confirmed that each of the wires coming off the distributer are sparking.
I tried changing the ECM.
I put in a new battery and new spark plugs.
The oil pressure sensor reads empty or one dot. Although that maybe normal before it starts?
There's a minor sound coming from behind the glove box. 3 quick, short sounds. Could be nothing.
Here's what the engine sounds like. Note how it kinda wants to start at the end . . . 

Secondly, I can't get to the self diagnostic screen. Normally that's some pretty good help. When I hold down the buttons, it just flashes every few seconds. It won't go into diagnostic mode. See here . . . 

I appreciate any feedback. This engine was silky smooth until we messed with the balancer. I'd love to get it fixed!
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               You need to investigate your harmonic balancer....I seem to recall that in the early 90's GM

used two different balancers on the 3.8 with different vanes on them for the crank sensor. My immediate

suspicion is that you were sold the wrong part. My shop got caught in this trap about twenty years ago.

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Yeah. Posted to 2 forums and have been responding to both. Right now it's at the mechanics. It took a lot to get the first harmonic balancer off. I want to make sure the new ones put on correctly so I'm letting the pros handle it. Thanks for all the information!

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Actually there were three but we won't count the 1991 with the tapered shaft. 3.8s had a single timing ring on the balancer, 3800s had the dual ring and dual slotted crank sensor. Oil pressure sender is notoriously inaccurate.


Video seems to have a occational hitch that sounds like way off timing, Can check with a timing light.


I wonder if the crank sensor got knocked awry when the cover was removed.


ps can't see in video but takes two fingers - off and temp up - to get into diagnostics.

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