04-01-2017, 02:30 PM
Hi all. I have a 1990 Geo Tracker 4x4 5sp ac convertible 197,000 miles. Am experiencing bad idling issues, for the past 3 months, MPG at 17 and rpm's at 2000 - 1500 and then surges adn drops between 1700 rpm and 1000 rpms. Going one by one found a bad IAT, missing gasket (3 screw one) for the air valve (wax thing) bad spark wires which I replaced today with some Bosch, replaced dizzy cap and rotor (china) w good quality and seems to be improving but since I was at the dizzy, I checked the vacuum advance mechanism with a vacuum tester and could not get the advance to HOLD any vacuum. Could not even get it to hold the 400mm that FSM calls for. It bleeds in air back immediately. Question is should this unit be replaced or did I do something wrong testing it. Also, this bad MPG has been since I got the car 5 years ago and 10k miles later. Replaced fuel tank, muffler system and have never gotten over 23 MPG hiway miles with the wind behind me. Compression reads when hot 1=170 2=172 3=178 4=187
#2 spark plug was dark and not beige like the rest but probably due to the bad wires. Also, this bad idling used to come around once in a while and then it would be fine, but like I said hte last 3 months I hardly use the car and idles like a mongrel. THoughts please.
#2 spark plug was dark and not beige like the rest but probably due to the bad wires. Also, this bad idling used to come around once in a while and then it would be fine, but like I said hte last 3 months I hardly use the car and idles like a mongrel. THoughts please.
1990 Geo Tracker 4x4 Manual AC PS Convertible US market (federal)