Talon not running right, need technical help

[cody]

Hi guys, been out of the game for a few years. I bought a 92 Talon with a blown motor. I pulled the motor and rebuilt it. Now its back in and there's something wrong. The car starts and idles really rough, to the point where I need to tap the throttle to keep it running. When I tap the throttle the slightest bit it revs up pretty high (reving it from the engine so not sure on the rpm but probably around 4k). There was a really strange clicking sound coming from the throttle body area, I could feel it while holding the intercooler pipe; almost like the butterfly was loose and snapping back and forth. I took off the upper intercooler pipe and the idle calmed down and it ran by itself at a steady rpm. When the engine was rebuilt, all the sensors and bolt on parts were reused with the exception of the injectors. I was missing one so I got a set from a friend who said they were from a 2g. Any ideas where to start looking to resolve this problem and get the car under control would be much appreciated.

 

[tektic]

Start by scanning to make sure your tps idle switch and isc are working
Check for vacuum leaks
then perform proper biss adjustment

If all else fails remove the fiav

 

[cody]

looked at the car today, found a throttle body on the shelf so I switched them out; everything's still the same. I did manage to hold a steady idle holding the throttle body open. I pulled each injector plug to try and isolate a bad cylinder and # 1 and 4 didn't change at all. I'm going to try a different ecu if I can source one from a friend.

 

[unistylef]

Those symptoms reminds me of ISC problems. Recommend pulling your ISC motor out and testing resistivity.

 

[tektic]

I don't remember saying change your throttle body. Did you do any of the things I suggested?
It is most likely your isc is out of rage because your biss is not adjusted properly.

 

[cody]

I changed out the throttle body because it had all the sensors on it already and they were known good. Didn't fix a thing. I ran a boost leak test, all is well. tried an ECU, no change. It really seems like its running on 2 cylinders.

 

[Steve885]

Take the advise from above.. Go to library, top of page middle read how to adjust your base idle ... And is your base timing set to 5 deg if not timing first then idle

 

[cody]

Dove into the talon and checked everything recommended. Injectors 2 and 3 aren't firing. The injectors are good.

 

[MellowVR4]

cas maybe

 

[MuffinMan7580]

Check your CAS, as already suggested. Sounds a little weird for it to be missing on only 2 injectors though. The 4 wires at the CAS should have 12v, GND, 5v, and signal to the ECU. Check for 12V and 5V. Easiest, and most likely IMO, you have a bad connection somewhere. If you just pulled the injector plugs off to see if they were working, then you could have good injectors, and a bad coil, since cyl 2 and 3 run off the same coil. Check all your connections (CAS, injectors, coils, and in between). Your best bet would be to make a logger cable, and log it to try and narrow the problem down.