steevano

I have a 1991 civic 4 door automatic that recently developed 2 issues. At start up the idle surges from 1500-2000 constantly and also does so when you let off the gas in gear. If you accelerate hard from a dead start it will usually shift fine through the gears (not always) but at normal acceleration it will shudder, shake and slip between 1st and 2nd but is fine through the other gears. When slowing to a stop the trans will shudder from 5mph until just before coming to a complete stop and quits just as you stop and it down shifts back into 1st. I recently replaced the head just prior to this and just replaced the air intake temp sensor with no change. I have another tranny to swap in but really dont want to go to that extreme if not absolutely necessary... Any Help at all would be greatly appreciated since I am almost to the point of filling the damn thing with Nitrogen Fertilizer, Diesel and....

4drEF

Bleed your coolant system.
Possible air bubble caught in the IACV/FITV that reeks havoc every time.

typeRef

adjust your down shift cable. i had the same shudder when it shifts to 2nd gear.

steevano

I replaced the Air Intake Temp Sensor with no luck. I did bleed out the cooling system 2x with no luck. When I swapped out the EACS it Idled fine for 5 minutes then back to the same. So I drained out and flushed the cooling system yesterday, refilled and bled it and everything was great for 10 minutes and then back to the same. I'll adjust the downshift cable now, there isn't much if any play in the cable so I'll loosen it up and see if that helps. Any tips or ideas on bleeding the air out of the cooling system other than the bleeder valve on the upper hose? It sure seems like an "Air Bubble" issue with the EACV/AITS or something. Could a MAP sensor cause this?