Need some help trouble shooting ongoing problem

**Drag Racer** · 05-01-2012, 05:19 PM

First of all new to this board hello all . Now let see how smart everyone is I have a 98 T/A that runs great until the outside air temp goes over 85 then the car will just shut down until it cools down then runs for a few minuets then quits . No codes water temp is cool . During the winter no problem. figure it is a sensor some place but don't know where. The low coolant light will come on from time to time but the coolant is full. Any ideas

**ADICECCA21** · 05-02-2012, 05:40 PM

Fans come on?

**Drag Racer** · 05-02-2012, 05:54 PM

Don't think so

**ADICECCA21** · 05-03-2012, 06:39 AM

Well I would start with that. Check relays, fan switch, etc. Get all the basic stuff figured out first. Kind of hard to diag a overheating problem if your fans are not even working.

**Drag Racer** · 05-03-2012, 10:08 AM

You're right, thanks

**Drag Racer** · 05-03-2012, 12:13 PM

gauge is not showing hot no evidence of overheating hot condition water level is full I do not believe it is over heating

**ADICECCA21** · 05-03-2012, 02:18 PM

I know there is no codes but i wonder if the ECT is not working when it gets to a certain temp. No signal from ECT means your notrunning. If the ECT was totally bad your car wouldn't start. But it is a thermister. Kinda like when a blower fan works on some speeds but not the others. I don't know that's a good one. I would check voltage right when the car dies next time and see if it where it is suppose to be. It's tough with no codes so you just have to start getting the easy stuff out of the way.

**ADICECCA21** · 05-03-2012, 02:19 PM

You could be getting a signal from it at cold but it could get hot and short out and not send a signal. That's all I can think of right now.

**Drag Racer** · 05-03-2012, 02:45 PM

Sounds like a good theory The temp gauge doesn't go to normal temp stays at about 170ish try to change the sensor and see what happens. Thanks

**ADICECCA21** · 05-03-2012, 02:58 PM

Yeah that's what i would start with. But the ECT doesn't go to the gauge. The coolant sending unit is what the gauge reads off of. But still I would try the ECT. If you have a multimeter test it if not they are pretty cheap to buy.

**pajeff02** · 05-06-2012, 11:15 AM

Get a scanner on the car and see what is actually going on. You are fortunate as the '98 temp gauge is the only one that actually works as it should... later years have "temp estimators". I would be taking a look at all the scanner data to see if you can spot an anomoly -- what is different on a hot day versus a cool day.

**Drag Racer** · 05-06-2012, 02:33 PM

Thats a good question car runs fine until summer then. it craps out after it gets hot changed the fuel filter when it quit fired right up but nothing in the filter . is there a temp shut off sensor that could be bad ? I am no amateur when trouble shooting older cars but this new crap is confusing too many sensors doing multiple things

Thanks

**pajeff02** · 05-06-2012, 06:38 PM

When you first start the engine, it runs in "open loop" and controls fueling off the tablesin the PCM. After the ECT reaches a certain temp, it kicks over to "closed loop" and fueling will then be controlled by the O2 senders. That's the simple version of how it works. If your ECT is off and reading too cold, the PCM will never switch over to closed loop and may run funny. A scanner will read both the ECT and open/closed loop. Other possibility is that a sensor is crapping out on you when it gets hot. However, this should normally result in the SES light coming on and a code being set.