A few days ago my 1995 SL1 quit running. It ran like a top, with decent gas mileage until about 200 yards before stopped driving completely. I felt it rumble, which I first attributed to a bump in the road. Then it seemed to lack power, the check engine light came on, and it ran rough. When I pulled off the road, it would go no more.

I've had both codes 33 and 34, which led me to disconnect the MAP sensor, but it ran the same. I've disconnected the battery, and the fault codes haven't come back.

I changed the fuel filter, spark plug wires (one was definitely bad), all four spark plugs, and a coil pack (tried it in both positions, no help). I've disconnected the MAP sensor and the TPS sensor (separately), but neither affected the engine operation.

The engine runs incredibly rich. I only had it running for about 10 seconds, after changing the coil pack, and all four plugs came out wet. The exhaust smelled like gas as well.

I have not looked at the ECTS sensor yet. I'll be doing that next. Any advice is appreciated.

EDIT TO ADD:
I live in the upper Midwest, and the engine had been cold since it broke down. The temperature gauge was climbing towards the halfway mark when it happened, and didn't seem erratic at any point.

 

Reading is fundamental

ETCS and it's CONNNECTOR
https://www.saturnforum.com/forum/general-tech-help-13/

I didn't know El Dorado Kansas was the upper midwest.

IPA 66.87.4.170

 

I don't know why my computer thinks its in Kansas. I'm in Minnesota.

I looked at the connectors at the sensor end and the wire end of the ECTS, and they were both corroded. I bought a new sensor with the brass tip, but the store didn't have the wire end connectors in stock. I'll look around for some tomorrow.

 

Both need to come from the DEALER if not it could be like spitting into the wind.

 

Would a regular GM dealer have those? I wasn't aware that there were any Saturn dealerships left.

 

I guess you didn't read the link. Reading is fundamental !

It said this.
"When buying either item get it from your local GM dealer servicing SATURNS."

https://www.saturnforum.com/forum/general-tech-help-13/etcs-its-connnector-6417/

ETCS and it's CONNNECTOR causes many different driveability, starting, lean, rich, and emission problems, yes including NO START. The reason is, it feeds the gauge and the computer information. Anyone can search a number of SATURN web sites and find information relating to the many problems that can come up. So if you have any of the problems listed above the ETCS and it's CONNNECTOR should be the first thing you look into. When buying either item get it from your local GM dealer servicing SATURNS. Do not buy from Al's Auto Parts and Furniture Barn. Oh and don't go to the junk yard for it.

PS: Early Saturns had two sensors and connectors. The Two wire feeds the computor

 

Sorry about that. I had so many tabs open I must have mistaken it with a different one.

I changed the ECTS sensor, which must have been changed before, since it was a brass one. I also changed the connector, which was badly corroded. The engine still runs poorly. I pulled the plugs again and tightened the gap slightly, and now the engine can idle without much help from me, but it still runs rough and starts hard. I also noticed a large amount of soot in the snow behind the exhaust pipe, but I'm not sure if has gotten worse or not.

EDIT: It was the EGR valve. The car runs beautifully now.