1994 Saturn SL1 Choke I think?

MAUER42

MEMBER
1994 SATURN SL1
4 CYL
FWD
MANUAL
179,000 MILES

First Im not sure if I have a saturn sl 1 or sl 2. How do I find out? OK here's the problem changed plugs wires checked coil packs and replaced O2 sensor. Now when I first start the car in cold weather it idles but is alittle rough but runs awesome (great pickup, really runs great) and as soon as it gets up to warm temp. (Within 5 min of starting) it begins to run terrible bad idle to the point of stalling and feel as though it is running on 2 cyl. The plugs get a lot of carbon deposit and black smoke when rev, high, so is my choke sticking? And which sensor is it, can I disconnect it and try running to make sure before I spend any money? Also there are no code when checked please give me some answers if possible idel goes up and down too about 1500 rpm then down to less than 100 and usally stalls out. Your thought. Thank you in advance

6 Replies

SATURNTECH9

MECHANIC
30,870 POSTS

Easy way to tell if sl1 or sl2 if the bumpers are black u have a sl1 if there painted to match the car then its a sl2 also if ur spark plugs face u when ur ooking at the car sl1 if they go threw the valve cover straight up and down then its a sl2. Now on to ur problem if ur car seems to be running rich and is blowing black smoke then the most likely cause is a bad coolant temp sensor there under 20 and controls the fuel by the temp of the engine. If ur going to replace it make sure u get one with a brass tip not plastic one the plastic ones crack and short out. Its located below where the upper hose goes on the head it screws into the head has two wires going to it a yellow one and a black one. To release connector u have to squeze it. Then it will unscrew use a 13mm deep 1/4" drive socket so u dont over tighten the sensor. Make sure the engine is cold and becareful u will lose coolant. Also inspect the connector they get corroded if it is then u will have clean it or replace it. Let me know how it goes.

SPONSORED LINKS

Was this

answer

helpful?

Yes

Monday, January 11th, 2010 AT 6:16 PM

MAUER42

MEMBER
5 POSTS

Thanks now I know I have a SL1, Again thank you and I will try doing what you said about the temp sensor, you said it was located going into the head? Well at any rate I will look for the 2 wires and colors you talked about./That seems really odd that the temp sen. Regulates the gas mixture base on the heat of the motor / coolant temp, so the choke is probably not staying open? Lots and lots of carbon on the plugs and out the exhaust, oh and my # 3 cyl. Has oil soaked plug so I'm thinking my valve guides are shot on that cylinder, or the rings not sure

Was this

answer

helpful?

Yes

Monday, January 11th, 2010 AT 8:52 PM

SATURNTECH9

MECHANIC
30,870 POSTS

Ur car doesn't have a choke it's fuel injected so when a engine is cold it uses more fuel so the coolant temp sensor tells the computer what temp the engine is so it can compensate for that and it also turns the cooling fan on at 226 degrees yeah the sensor has two wires the other sensor only has one that one is for ur temp gauge let me know how it comes out.

Was this

answer

helpful?

Yes

Monday, January 11th, 2010 AT 9:44 PM

MAUER42

MEMBER
5 POSTS

Ok, got the sensor out and yes it was cracked and a blue crust stuff was inside the crack, gonna grab new one today and see what happens. Thank you for your advice really cool to do, thanks again. Let u know what happens.

Was this

answer

helpful?

Yes

Tuesday, January 12th, 2010 AT 12:45 PM

MAUER42

MEMBER
5 POSTS

Well installed sensor and running fast and furious, wow who would of thought a $9.99 part could be the problem and it is tucked / hidden pretty well too. So just wondering what is normal idle speed? Mine is around a grand 1000 rpm but is dropping to half that at a red light? Is this normal idle? I know Ill never get it perfect with 180,000 miles but what a difference since getting ur advice. Thanks and any other help is always apprecated thank you again!