1990 cougar xr7 auto
I installed a rebuilt motor and swapped the tranny for a M5R2. Also changed the exhaust too… stock exhaust manifolds to 2 ¼ pipe to a high flow resonator (I haven’t finished the rest of the exhaust yet) No cats and original O2 sensors in original positions.
When I first fired up the car it started right away and sounded great. After it warmed up a bit I took it for a run. I ran it down the road about ½ mile or so when I noticed my temp on my after market gauge was at 200 and rising. I turned around and headed back. When I got back my temp was 230 and I noticed the fan was not on. I quickly unplugged the fan and ‘hot wired’ the fan to the battery. The fan turned on and the temp returned to about 190. At no time did the stock temp gauge go past ½ way. With the fan ‘hot wired’ I went for another run. I went for about 2-3 miles, car ran great, felt great, temp 195ish. On the way back, as I was down shifting the car almost stalled and when I returned to the driveway it was idling really rough. I shut the car off and checked everything, found nothing. The next day I fired up the car and again it idles rough.
At idle it’s like the computer is searching or a sensor is confused. It almost stalls then revs up a bit, coughs, revs up a bit and sometimes stalls. The exhaust smell is really rich when it does this.
I don’t think there is anything wrong with the motor or timing, when I rev it up to 2000 it smoothes out and sounds ok. (And at first it started right away and idled and ran great) I don’t think any damage was done running up to 230F (I no this is hot but it’s not really hot) I’ve looked for a vac. leak but haven’t found any (yet). Could any damage have been done (to the computer) by unplugging the fan and ‘hot wiring’ it? Also could I have lost an O2 sensor due to the open and unfinished exhaust (no back pressure)? Or have I lost another sensor. I put a code reader on it and show no significant codes. Any thoughts or suggestions would be greatly appreciated.
(The fan issue was a bad sending unit)
I installed a rebuilt motor and swapped the tranny for a M5R2. Also changed the exhaust too… stock exhaust manifolds to 2 ¼ pipe to a high flow resonator (I haven’t finished the rest of the exhaust yet) No cats and original O2 sensors in original positions.
When I first fired up the car it started right away and sounded great. After it warmed up a bit I took it for a run. I ran it down the road about ½ mile or so when I noticed my temp on my after market gauge was at 200 and rising. I turned around and headed back. When I got back my temp was 230 and I noticed the fan was not on. I quickly unplugged the fan and ‘hot wired’ the fan to the battery. The fan turned on and the temp returned to about 190. At no time did the stock temp gauge go past ½ way. With the fan ‘hot wired’ I went for another run. I went for about 2-3 miles, car ran great, felt great, temp 195ish. On the way back, as I was down shifting the car almost stalled and when I returned to the driveway it was idling really rough. I shut the car off and checked everything, found nothing. The next day I fired up the car and again it idles rough.
At idle it’s like the computer is searching or a sensor is confused. It almost stalls then revs up a bit, coughs, revs up a bit and sometimes stalls. The exhaust smell is really rich when it does this.
I don’t think there is anything wrong with the motor or timing, when I rev it up to 2000 it smoothes out and sounds ok. (And at first it started right away and idled and ran great) I don’t think any damage was done running up to 230F (I no this is hot but it’s not really hot) I’ve looked for a vac. leak but haven’t found any (yet). Could any damage have been done (to the computer) by unplugging the fan and ‘hot wiring’ it? Also could I have lost an O2 sensor due to the open and unfinished exhaust (no back pressure)? Or have I lost another sensor. I put a code reader on it and show no significant codes. Any thoughts or suggestions would be greatly appreciated.
(The fan issue was a bad sending unit)