Engine stall's for no appearant reason

[mark1111]

I have a 97 Geo Tracker and sometimes the engine dies when I stop at a red light. It only does that when the engine is hot. The engine stall's suddenly, no matter what I do. It then takes a couple of turns to get it started again. I think it might be my catalytic converter that would be plugged. Any ideas.

[jtgh]

tells us more about it.
5 speed, automatic ?
when the engine dies, and you turn the key back to ON
not started., is the check engine lamp lighted.

its not the cat,
a plugged cat kills power and speed.
it will idle fine.

is your Idle normal just before the dump.

No check engine light is odd.
you might just need a tune up.
plugs, wires, etc.
check plugs for oil or carbon fouling.

[Shconer]

Could be a sticky IAC valve.

[mark1111]

It's a 5 spd, and when I go to start it again it idles at about 400-500 Rpm for about 10 seconds then goes back up to 1000 Rpm, after that it smells very bad at the tail pipe. It Only seems to die when I'm downshifting and when I look down at the gauges all the lights that are usually ON when you have the key pass the Accersory position, just before you start the engine. I have new plugs and wires.

[jtgh]

engine dies on 5speed 1.8 Liter? , 4wd?
The hard ones I like.
it could die for a many reasons.
but ..
mostly
1.
lack of fuel (too lean or none)
2.
too much fuel loading up, fouling plugs and causing the cat. to glow red hot and stink like crazy.
3.)
loss of spark. ( but misfiring can load a cat too)
4) fuel pump dying.

I think? ( just based on your words) it is too much fuel.
Checking the spark plugs would confirm this.
pull one and look, is it oil fouled or black with carbon that stinks of fuel or is it nice and white/cream color?.

can you look under your dash and behind any ash trays for the 16 pin DTC connector. see photo.
it must look like this exactly!

questions:
1. does the car while running , show the CEL lamp.
THe CEL is on for testing during Igniton on , no start and when the car dies. Yours glows so it is not burned out. good.
I am asking to look at the lamp only while the engine is running? This is an important diagnostic aid.

To much fuel could be caused by many things but
mostly:
1.) TPS bad and or the MAF is bad.

you car is a 1997 and We need to know if your car is
OBD2 level. in the USA this became manditory in 96 mid year. Your profile is empty making it hard for me to know where your car was sold.

to all posters:
( it is good when asking for help to tell your engine size, transmission and country of origion , 2wd,4wd)
There are vast differences between regions.

This kind of problem is the most difficult to diagnose due to the lack of information.
"RICH , LEAN or Spark"
how ever:
The IAC stuck would be a good example of to little AIR. (too much causes racing)

If you suspect a stuck IAC then just step on the gas pedal a little bit to keep the engine running.
if this works, then suspect the IAC !

last quesiton that will help.
look at the air induction pipes between the Air cleaner and the Throttle body.
is there a black box that as wires coming out of it, that is called a MAF ? it could be very dirty !
do not touch the parts in side or try to take it apart.
only spary the inside fragile parts with CRC MAF cleaner.

If yes , it could be bad, or the TPS (throttle postion sensor).



last question.
How many oxygen sensors are attached to your exhaust system?

[geo toy]

My 97 tracker was doing the same thing. Dirty throttle body had it cleaned and it is running great now.

[jtgh]

dirty throttle body, means , iac is clogged.
The IAC , sets the proper air to allow idling.
if it clogs and sticks open , engine races
if it clogs and sticks closed, engine will die.
if it is clean the idle will be perfect all the time.
all cars do this ( because of EGR and PCV contam.
)
to bad he didnt mention the Check Engine light.
this is an OBD2 level ECU car ,it sets codes for many problems. (soft and hard fail).
pull the codes. go to AZ and ask to pull codes.
pending or actual.

[mark1111]

thanks for all the info. I've been really busy at work so I didn't have a chance to do any work on the tracker. As soon as I get a day off I'll go over the list and let you guys know what I have found.

thanks