1G Help with my 1g. Not starting, running hot..

[92_talon_awd]

I was driving my car a few weeks ago and for some reason the fans stopped cycling on like they are supposed to. The car overheated and blew the head gasket. I had the head machined and replaced the head gasket.

The car is now having a hard time starting when it is cold. It fouls out the spark plugs extremely fast and the only way I can get it to start is to hold the gas to the floor and when it does start, it doesn't want to idle right. It idles around 500 rpm.

It is also running warmer than I would like so I haven't really driven it much since the head gasket replacement for fear of blowing it again. I replaced all of the temp sensors and the thermostat but no luck.

Something strange about the fans is that I had them wired together so they were cycling on and off properly and I was also able to turn them on with the A/C button in the cabin, I've deleted my A/C. When they stopped cycling on and off properly, the A/C button also stopped turning them on but I can have them run constantly by using a vampire clip on the two wires going to the sensor on the bottom of the radiator.

Any ideas?

 

[1990AWD]

I'm leaning towards a bad temp sensor (the one for the ecu).

if that sensor is bad it will cause bad starts, or not at all, and may have been a problem ever since your headgasket went.

 

[92_talon_awd]

Okay, which temp sensor is that and how can I test it?

 

[Stone'S GSX96]

Okay, which temp sensor is that and how can I test it?

Yeah most likey that temp sensor. I cant recall witch one it is but I can look tomorrow and best way to test really just get a new one. Depending on witch one it is it cost 10-25$ at auto zone.

 

[sniver]

heres what the fsm says

<table style="width:auto;"><tr><td><a href="http://picasaweb.google.com/lh/photo/O0aSr2cjooeFN0G4V9XiOKqsuFuYsrgaTTk9Q9-cPQc?feat=embedwebsite"><img src="http://lh5.ggpht.com/_Ziaf2eJ7svA/TRlj5t75wmI/AAAAAAAAAoc/n6BhdBcBpqg/s800/cts%20diagnosis.JPG" height="285" width="585" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="http://picasaweb.google.com/tyrosniver/DSM?authkey=Gv1sRgCPevnciGoab7KQ&feat=embedwebsite"></a></td></tr></table>

and it should be this sensor

You must be logged in to view this image or video.

hope that helps

 

[Stone'S GSX96]

heres what the fsm says

<table style="width:auto;"><tr><td><a href="http://picasaweb.google.com/lh/photo/O0aSr2cjooeFN0G4V9XiOKqsuFuYsrgaTTk9Q9-cPQc?feat=embedwebsite"><img src="http://lh5.ggpht.com/_Ziaf2eJ7svA/TRlj5t75wmI/AAAAAAAAAoc/n6BhdBcBpqg/s800/cts%20diagnosis.JPG" height="285" width="585" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="http://picasaweb.google.com/tyrosniver/DSM?authkey=Gv1sRgCPevnciGoab7KQ&feat=embedwebsite"></a></td></tr></table>

and it should be this sensor

You must be logged in to view this image or video.

hope that helps

Very right you are!

 

[92_talon_awd]

Thanks everyone, I'll test it and post my findings. Kind of funny the manual says it's in the intake manifold.

 

[92AWDHX40]

Must be wrong sensor no sensor for coolant purposes in there, let us know.

 

[92_talon_awd]

So the sensor checked out according to the test. When I put the sensor back in the car and hooked it up, the resistance between the two wires going to it went to 1.7 kOhms but when they are disconnected the resistance across the sensor is 5.7 kOhms.

Is this right or does this point towards a problem in the harness? Is there some test I can do at pin 20 of the ECU to see if it's getting the right values? Thanks

EDIT:

I tested the circuit as the manual says and I'm getting the correct voltage from the harness and the other pin has ground. So the circuit tests out as it should which means I'm still lost.

EDIT:

I found a problem with the A/C coolant temp sensor (the upper most one on the thermostat housing). The manual says that it's supposed to have system voltage at the black with green stripe wire when the connector is disconnected and the ignition is turned on. I don't have voltage. There is continuity between the black and green and pin #7 of the ECU like there is supposed to be so I guess the problem is that the ECU isn't putting voltage to pin #7. Does anybody know where the ECU gets the voltage for pin #7? Thanks.

EDIT:

Okay, I tested all the wires that I could going to the ECU that are supposed to have power at different times and the only problems I could find were with pin #16 (barometric sensor) and pin #8 (intake air temperature sensor). I have the MAFT Gen II and those two wires are tapped from the translator box.

The box is set to ouput a constant 2.5V to pin #8 and a constant 5V to pin #16. The box is putting out 5V to pin #8 and 0V to pin #16. I checked the box and it's still set to output the proper voltages, it just seems like it isn't. Maybe a problem with the translator box itself, not sure.

I'm guessing this could cause the car to not start so I'm going to try and get my hands on a 2g airflow meter to hook up instead of the MAFT box and see if that starts the car. I'll post my results and if anybody has any suggestions, I'd appreciate them. Thanks.

 

[sniver]

I have no experience with the maf translators, so I can't be of much use here. Is the maft zeroed out, or is it adjusted? Also do you have some way to data log?

I second the idea of trying a stock maf sensor.

Once the motor starts, whats the afr?

 

[92_talon_awd]

Well, I got the motor started by using a 2g maf and setting the MAFT box to input from a 2g maf. It runs rough but that's probably because I didn't have it in the airstream, only hooked up and sitting in the engine bay.

I just wanted to see if the stock baro and temp sensors were what were keeping the car from starting and it seems like that was the problem. I guess I'll have to send my MAFT box to full throttle and have it fixed.

 

[1990AWD]

good job figuring it out; it always feels good when you solve the problem