93 SC3 starts then stalls in cold weather

[Lurker1999]

I'm new to the forum and just starting to learn about cars. I've got a problem with my 93 SC2 automatic (45k miles). Just this winter it has started having problems starting in cold weather. The car starts without problems (alternator and battery replaced last year) but then will start shaking and will stall if I don't press the accelerator down. This only happens on the first start of the day and only if it's a particularly cold day (I park in an underground garage so it doesn't get below freezing, but it is moist down there).

Last weekend I took it to the dealership where they found a loose spark plug wire, replaced the wiring harness and reprogrammed the PCM. Since then it hasn't had problems stalling. The car would sometimes literally shake side to side though when I started it but would subside after about 30 seconds and then be fine.

This morning the car died again as would happen before the repairs. I just called the dealership again and will be taking it back there on Monday. However I would like some advice about what to discuss with them.

I searched through the forums here and some of the things people have mentioned are a vacuum leak, looking at the EGR, throttle body, idle air control valve. I don't have the tools on hand or the experience to do this myself currently and I really need the car fixed quickly since I need to drive more for work the next two weeks. I do plan on checking out the Chilton manual from the library before I go to the dealership but I'm not sure how helpful that will be.

Also do you think I will have to pay for the initial diagnostic eval or should the fact that the car is still having the same problem be a cause for them to look for the problem for free?

All advice would be welcome..

[Gerry Proctor]

Cold, moist atmosphere will test the capacity of your ignition system. If you haven't done a tune up (plugs and wires) on the car in a while, that might be your first step. You should also check the coil plug towers for any signs of arcing.

The shaking you experienced was a misfire either due to poor ignition performance or poor fuel management. If it's fuel related, you're probably going to need a new temperature sensor (fairly cheap and easy to replace and should be considered your prime suspect). Of course a complete tune up would help as well.

If the dealer does a complete diagnostic, then they'll be able to check the sensors, fuel pressure and the ability of the fuel system to hold pressure, as well as an ignition check up.

Whether the dealer will cover any of the costs depends entirely upon what they did previously and what they'll do on the second go-around.

[Lurker1999]

I took it to the dealer today. They checked it over for free but couldn't find anything. The invoice lists: IAC passed functional test, coolant temp sensor in specs, plugs and wires in specs, no codes present, reset spark comps to possibly help

The service guy recommended changing the fuel filter and looking over my records I don't think that's ever been done. The car's 10 years old but only has 45k miles on it.

[wolfman]

You have to remember that you DROVE the car there...hence it was not truely "cold" per se'. "Stalls when started cold" is nearly always an initial idle air/fuel mixture problem. A sticky IAC (idle air control) valve being the prime suspect. Just because it "tested" fine, don't rule it out. A little varnish/gum/dirt can be agravated by COLD temps and make it stick on startup. I'd suggest you clean your throttle body and the IAC passage within it yourself BEFORE shelling out the $100+ that the dealer will charge to replace the fuel filter. IF that does not clear up the problem, then perhaps consider replacing the filter. Fuel filters DO NOT wear out with "age" but do clog up with fuel flow over time, hence I'd doubt the fuel filter is the cause of your problem.

[Lurker1999]

For just under $12 (cleaner, gasket, locktite) I cleaned out the throttle body today. My first effort at anything under the hood, yay. Anyway, it seems that in the two visits to the dealer they had "inspected" the throttle body but had not removed the gunk caked to it. So far the car is running fine. I'll have to wait for a really cold day to see what happens though.

The guy at the dealership sold me the wrong gasket so I had to carefuly straighten out the old one that was slightly bent, clean it off and put that back on. I plan on driving to the dealership again tomorrow to raise hell about the part after I specifically asked them three times before I walked out with it.

[t0pk0w]

the shaking could be you automatic choke it may be a little slow (why i dont know) but if it is it might not give the engine enough fuel for a cold start right away and if it drops to about 300 rpm it will shake but if it does that again watch your Rs (if you have a tach) thats just what i think