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Starting/stalling issue

  • Thread starter Thread starter Moco
  • Start date Start date Jul 8, 2008
M

Moco

Member
Nov 10, 2002
35
0
6
Arlington VA
Jul 8, 2008
#1
  • Jul 8, 2008
  • #1
Hoping for some input here. I have two questions and I think their causes are probably interconnected or at least overlap. Situation is as follows: The car is a stock 99 Gt with 5sp. Completely stock with 124K miles. She runs great, idles well about 98% of the time and gets about 23 mpg with mixed driving (the good idle and mpg probably means she is in a good state of tune).

ISSUE I

The first problem that I've been encountering over a period of weeks is that the car will meekly die in situations where I am coasting to a stop. This rarely happens but it does happen a handful of times a month. For example, if I am approaching a stop sign at a low rate of speed such as <25 mph and I depress the clutch to coast to a stop, sometimes the car just dies: the RPMs drop to 0, and of course I lose power steering and braking. There is no bucking or sputtering, the car just simply and quietly stalls and shuts off. Again, this happens very rarely but it is a serious enough issue that I want to get this worked out. Lately, I have noticed that in situations where I am coasting to a stop, the tach has started to dip just under 500 rpms - but motor does not die. Once I come to a stop, the idle returns to its normal ~700 rpm range. Any suggestions as to what is the cause?

ISSUE II

In the last day or two, I have experienced some rough starting. This morning, getting ready to go to work, I had to crank the motor 3 times and gas it before it finally stayed running on the 4th time. The first 3 times, it tried to maintain an idle but the tach just sunk to 0 and the motor died. since my gas tank was low, less than 1/5, I chalked this up to low level of gas and maybe a dirty/old fuel filter. However, this afternoon, when I started the car, the idle again dipped to 400 rpm and kinda hovered there until I gave it some gas and it settled into a normal idle.

Please help diagnose whats wrong. The car runs great otherwise and is a pleasure to drive. But I need to fix these anomalies to make it a perfect running daily driver.

Thanks
 

Stark77

Member
Jun 11, 2008
501
0
16
Tallahassee, FL
Jul 8, 2008
#2
  • Jul 8, 2008
  • #2
IAC is possibly shot
 
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