1991 Eclipse

[tmaxx411]

I will be picking up a 1991 Eclipse Base for a Daily tomorrow. It has the 1.8 engine in it. My issue currently is that it wont stay started until it warms up, then once it gets a bit hotter, it wont run right again. The guy im buying it from says its the temp sensor, which sounds right, but at the same time, the temp gauge on the dash works. what im wondering is if it could be something else entirely. thanks

 

[agentorange313]

There are two coolant temp sensors, one that sense the temperature for the ecu and one that corresponds to the gauge on your dash. The one for the ecu is for open and closed loop mode.

coolant temp sensor:
https://www.extremepsi.com/store/product.php?productid=22700&cat=1060&page=1

water temp gauge sensor:
https://www.extremepsi.com/store/product.php?productid=23816&cat=1060&page=1

whats up new jersey

 

[loco4G63]

I would check the ignition coil. I know when they start going bad wether cold or hot they can start giving those symptoms. When they get too hot they stop working all together sometimes. My advice is start with a basic tune up. Plugs, wires ( also check these ### it could be the issue as well......as heat increases so does resistance and spark plug wires don't last forever. Also change the cap and rotor button on the distributor. A basic tune up is cheap and always a good investment in a used car. No matter what though keep it simple and start with the basics.

 

[tmaxx411]

ok ive got an update. new coolant temp sensor, new wires, and new plugs. car runs decent, but is still a PITA to start. it stalls at least 5-10 times before it will idle correctly. regardless of if its a cold startup or if its hot. im stumped on this one... anyone have any ideas?

 

[Boostinsideways]

Check your BISS Screw on the throttle body, check the ISC (also on throttle body bottom side, 6 pin plug). You should remove the isc from the throttle body and leave it plugged in. Have some one else turn the key to on, then back to off. The isc should move smoothly in and out. If it just kinda twitches its shot.

 

[tmaxx411]

Ok, I'll check the ISC once this storm passes. I also uploaded a video to show what its doing. From 0:25 to 1:25 the gas pedal doesnt move. Also, the CEL comes on and off randomly, but once you get it to idle, it stays off.

1991 eclipse 1.8 - YouTube

 

[DSM1G90]

Check your BISS Screw on the throttle body, check the ISC (also on throttle body bottom side, 6 pin plug). You should remove the isc from the throttle body and leave it plugged in. Have some one else turn the key to on, then back to off. The isc should move smoothly in and out. If it just kinda twitches its shot.

Psst..."sorry, but 4G37's don't have the same junk as the 4G63 setups"

He has no BISS screw, nor ISC .... they're a bit plainer setup(I also have a '91 1.8 with an auto with over 200k miles on it .. runs like a dream for I use it as a DD and leave the Turbo at home unless I want to be a little crazy on the road and freeways . and I had to replace my temp sensor as well due to the same basic problems this OP is writing to us about), but do plugs - (NGKBPR6ES-11 gapped at .044).

With a blinking CEL light means that you got an idle speed problem(O2 sensor is reading major lean mixture why the CEL is going crazy on you and why it dies on you) and that takes a two stage test to get the idle correct so the CEL doesn't come on (Oh, do you have a temp sensor on the EGR - which was a California requirement and not 49 state requirement? If you have a wire heading to the EGR and a sensor right next to it, those sensors when they go out will throw a CEL in a quick.) Basically, the first step is to set the throttle plate correctly so the TPS can be adjusted correctly. Then you do the actual base idle speed setting - which is 750rpms at idle.

You oughta think on doing belts as well. You need two - main timing and balance belts and a 10yr old can do belts on a 1.8L since they are so easy to do.

Some tips to throw at you .. good luck - DSM