1997 SL2, tough start, rough idle, stalls.

Heres one idea...Stop going to that dealer and find a real shop that actually knows how to diagnose a car. Knowing how well things have been kept up on your car would be helpful. Not much we can do other than throw out guesses here.

In article , snipped-for-privacy@intertainia.com writes: |> Hello Everyone, |> |> |> I was wondering if anyone can help us on this one. This has been |> going on for years. Every so often, my saturn will not start at |> first. Cranks, first but fails to continue running. After a few |> attempts, it then starts but runs rough and idles like crap. Have to |> hold the gas pedal to keep if from stalling. |> |> I've been back and forth to the dealer for YEARS now with this, but |> they can't find what causes it. The find the code for the actual |> stall, but not for the cause. The car wasn't on the fuel pump recall, |> or anyother lists ( which btw scares me from ever buying another |> saturn, if this saturn is the best they made, oh doomed). The car |> only intermittently does this, maybe 2-3 times a year, but at the |> worst times. Like wifey driving at night, on very-very cold days, or |> very very hot days.

This is a long shot. I have a 1994 SW2 that showed the same symptoms, except in my case it was continuous, and not intermittant. My car showed no codes of any kind. Its data interface is OBD-I, whereas your car, being 1997, should be OBD-II. An OBD-II car SHOULD be have more extensive tests for bad sensors.

Anyway, on my car (maybe not on yours), there are two temperature sensors in the driver's end of the cylinder head. The upper/forward one is the coolant temperature sensor, and is fully described in the factory service manual and wiring diagrams. The lower/rear one (about

3 inches away) is NOT mentioned in the factory service manual! This second sensor was the one that caused the problems: running rich, full-scale O2 sensor output, unstable idle speed, stalling at idle when hot and on acceleration, and hot starts requiring pedal on floor (flooded start procedure). After a local shop found the problem and replaced the sensor it, the car is running well again. Credit to them: they did not have to replace anything else.

Sad thing about this......

It's been happening so long, and I've moved several times, that three seperate dealers have not found the problem. Each dealer is 50+ miles from one another.

:(

Start by replacing the coolant temp sensor in the head. This is generally the cause of poor cold starting.

Note your idle speed when the car starts and runs. I bet it's high, like over 1,000 rpm. That's a hint the CTS is bad - it also regulates idle speed - the hotter the car, the lower. If the car thinks it's warm or hot, the mixture leans out. Not good for cold starting.

You're not saying where you are or what very very cold or very very hot is, but if you have normal weather most of the time, you might not noticed this and itcan go on a long time - this won't throw up a trouble code if the sensor is somewhat working.

Temperature extremes is the clue here. Start with the CTS.

Oh yeah, and as always, take a peek at the throttle body and see if it's clean of ront. Should have shiny plates and little carbon buildup. If it's carbony, goopy, or has a lot of junk, clean it out while you're replacing the sensor - it's cheap, easy, fun, and can help too. Just pull it out, take off the sensor and IAC, and use throttle body cleaner and an old toothbrush to get everything out. Then wipe the IAC off, put it all back together, and bolt back on (watch the gasket position).

Typically any time I start the car, it's intial idle is over 1000rpm for the first few mins. Isn't this normal?

Now Pennsylvania.

A few years ago, I pushed for a real check on the system and I was told a temp switch was 'out of band' but wasn't causing any codes. They replaced it at my request, and the car ran very well for a long time. Now we are getting the intermittent failed starts and rough idles and stalls. Might be a pattern here.

As for carboning up the throttle body, this seems to be a major complaint from most SL owners. :(

thanks for your reply it helps.

Tom @

Yeah, that is. But, if it stays up there, or very quickly drops down, or such, that's a bit bad.

I'm betting on the CTS. Some aftermarket or non OEM ones tend to be a bit flaky. Then again, so do some genuine Saturn ones...

Not a huge problem, but it does lead to sticky operation and weird things happening. And it's pretty easy to clean anyway.