1992 Saturn Black Smoke

i would check the TPS also the MAF or air intake sensor dependent on vehicle same thing.

also scan the engine for trouble codes. will pretty much tell you if its possible o2 sensor failure also. not so much guess an check.

Is it possible that it has a bad fuel pressure regulator. The manual says there is one, and that is a possible symptom, but I can't find it.. It looks like all I have is a throttle body with one fuel injector on top. I follow the fuel lines and I don't see a fuel regulator.
Thanks Again

[quote:44c2e71915="RonH"]My granddaughter has a 1992 Saturn with a 1.9 liter engine, and 115,000 miles. When you start it it idles rough and bellows out enough black smoke to leave a mark in my driveway. It emits black smoke when driving also, and really stumbles when taking off from a stop. It really uses up the gas. I checked the TPS and got .5 volts throttle closed and approx. 5 volts with WOT. There are no trouble codes in memory. It has new spark plugs, and air filter. Hoses and everything seem to be in order. Is it possible the fuel injector could be partially stuck open. I would appreciate any input.
Thank You[/quote:44c2e71915]

Another thing to check would be the injector o-ring. My father had an 87 Tempo that bellowed black smoke but stalled right away because the injector o-ring was broken.

-Steve

It was the coolant temperature switch. The new one costs $9.99 at the auto parts store. It had a crack in the probe. The only problem I had with it was another switch about 6" in front of it that looked almost identical. It has different terminal connection than the coolant temperature sensor. I guess it was the coolant level sensor. I got the fuel pressure regulator back together, and everything seems good to go. The car runs good again.