Literally....I'm trying to sell my car and then this happens...Never happend to me before.

I think this has a lot to do with the fact that the car was running on the warm side. (hot day and I don't believe he took the car on the freeway).

Car is already warm. I start up the car, no engine service light...everything seems fine, then the idle drops to about 400 RPM, hicups, then everything is fine. However, after the "hicup" the engine light comes on.

Let me know if you have any ideas! Thanks

PS - car has LT4 Hotcam kit, headers, tuning, and the usual mods.

 

And the code for the SES light is?

 

I have 2 code readers. None of them show anything even though the light is on. I think this has to do with the fact that the light comes on after the car is running and shuts off until the car is started and warm again.

I let the car cool down last night then took it on the highway. I thought all was fine till I hit the off ramp. When I put the clutch in and started to slow down, the engine stalled. It did the same thing on the way home.

 

I plugged in the code reader and under "past codes" I get code 36. Anybody have any ideas?

 

DTC 36 is a problem with the high res pulse from the Opti. It doesn't necessarily turn on the SES light though, and even if you have the code, you aren't likely to feel any difference in the way the engine runs. Might be worth checking the harness connector on the Opti for corrosion.

If the SES light comes on, the codes should be stored in the PCM, even if the light goes off, or isn't on when you restart the engine. Are your code readers true OBD-I scanners, or are they the "short the pins" scanners that don't work on 94/95 cars?

 

I tried both types and got code 36 with the actual scanner, not the jumper type.

 

same problem on my 94 lt1. shop pulled a code 36 which is a low res pulse or another way of saying the 600.00 sensor behind the water pump is bad. any truth to this. i have put in new plogs,wires and a new coil yesterday. mechanic wants to put a new cap assy and sensor this weekend, but thats a lot of c notes....any ideas? it wont start till the ses comes on , then runs alright for a while. turn it off, the light goes away and it wont start untill it codes again...please any help is app.

 

Not completely correct... DTC 36 is loss of high resolution pulse pattern. The source is the optical sensor module in the Optispark distributor. The code for the loss of the low resolution pulse is DTC 16. It you had that as an active code, the engine wouldn't be running. With DTC 36, the engine should continue to run.

As noted above, could be a faulty sensor in the Opti, or it could be corroded or damaged harness wire on the Opti.

The Opti has two parts.... the "base" which bolts to the front of the engine and is driven off the nose of the cam contains the bearing and the optical sensor. The other 1/2 is the cap and rotor, that screw onto the front of the base. Best known replacement is a stock AC/Delco unit (about $300 from discount GM parts sources). That's an "unvented" unit used in the 93/94 models. There are also replacements from MSD ($500) and Accel (not sure if they have an unvented model yet) but none of these have been available long enough to know if they are any better than stock.

You can do the work yourself, limiting the cost to a little over $300. If you go through a dealer, they'll charge you $600 for the part and $300 to install it. Your mechanic may offer you better labor rates and you can supply the part, if you can't do it yourself.