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1988 Mazda 929 Repair Question


Topics covered: Choke, Sensor, Coolant.
Mileage: No information provided.

Asked on September 18, 2008

1988 Mazda 929


i asked this question last week sorry for the late reply
my mazda when it is cold idles at about 2500revs
for about ten minets and then fluctates between 1500 to 2500 rpm i cant drive the car for at least 15 minets every day when it has reached operating temp. it idles real good 650 rpm, i am trying to disable the auto choke, but i cant find how to do it i have the manual on the car but that is no help. So could you please help me out on how to disable the auto choke thankyou from brian...
Avatar Asked by brijo

Answer

Replied on September 18, 2008

Fuel injection doesnt use an auto-choke, it reads the coolant temp via the sensor to see what the mixture should be. You may have a bad coolant sensor or maybe a bad o2 sensor that needs to heat up completely to work properly. Is the check engine light on?

Tiny Answered by 2CarPros Jack (expert)
12,033 answers provided
Replied on October 3, 2008

The 88 929 also has something called a BAC/ISC valve on the driver's side valve cover. This part is what will cause fluctuating idle issues. It can be removed and sometimes cleaned out enough to start working properly again. The alternative is to get one from either ebay or a yard as they are over $700 at the dealer. Spray it with carb cleaner, let it sit, slosh it around a bit. I own two of these cars and have owned 5 others, 88's and 89's.

Tiny Answered by rmmagow
2 questions asked