I just put a motor in my 88 gtu and it idles rough and having trouble getting the timing marks aligned.The car has power when driving but will either stall or idle rough when it returns to idle.


When I first start it up it goes to about 2500 rpm's and then drops down till it dies unless I give it gas until it warms up, but it still idles rough,if I hold the gas at a little over 750 rpm's it smoothes out good.Would a leak at the first cat cause this?Why won't it hold a good idle and why doesn't the aws work?Also what does it take to fill the cooling system,I keep adding coolant to it, just seems to disappear.There is no smoke coming out the exhaust and no visable external leaks.The radiator cap does hiss when I open it after I let it cool off.

Any help will be highly appreciated.
Danny

 

Forgot to mention it always fires right up.

 

coolant issue: on the end of the top radiator hose when it leaves the radiator is a small round "peg" that takes a phillips head screw driver you have to bleed out the air so it won't disappear.idle issue: has it been really cold? i live in jax fl and when it gets below 45 or so the next morning i have to rev slightly until temp starts to come up,then let it idle down until she is warmed up. if it hasn't been cold, then you may need to adjust your tps, check all the connections,anything little and stupid . a good idle at 750 or so is right (bounces around a little )

 

make sure that u have no vacuum leaks or that there is no air leak

 

I have done that,all the gaskets and some of the vacuum hose are new.I think I will try removing the cas and realign it.Also the the throttle cable hasn't been adjusted yet,could that have something to do with my problems? As for the missing coolant,I found it, it's all going into the resevoir,, needs new radiator cap.


Thanks
Danny

 

Turns out I somehow got a ground wire stuck underneath the oil filter.It has a black resister type thingy on it.What is that ground for?Seems to have smoothed out a whole lot after correcting that dumbass mistake I made,find out in the morning.

 

bump