night and day...
07-12-2001, 09:27 PM
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Join Date: Jun 2001
Location: Dearborn, MI
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night and day...
I test drove an 87 (coupe) and 91 (targa) 911 today. WOW! What a difference from the 915 transmission. The G50 was so smooth and pleasurable to drive. That just narrowed my search to 87 and older.
I do have a couple of questions, all of them on the 91 targa. Is it normal for the idle to be slightly lumpy (rough)? Is the ventilation fan always on or is there a way to turn it off (I had the **** on "0")? How do you check for an updated distributor housing and why are there two distributors?
Thanks,
Adam
I do have a couple of questions, all of them on the 91 targa. Is it normal for the idle to be slightly lumpy (rough)? Is the ventilation fan always on or is there a way to turn it off (I had the **** on "0")? How do you check for an updated distributor housing and why are there two distributors?
Thanks,
Adam
07-13-2001, 03:24 AM
#3
Adam:
As far as your questions on the '91 Targa go, here are some answers:
1. The degree of "roughness" of idle is VERY difficult to diagnose over the internet. I have a '91 C4 w/21K on it. At idle, it tends to hang around the 700 RPM mark...once in a while it will surge slightly (maybe about 50RPM, maybe about once a minute). The idle itself is generally smooth other than what I've described.
2. If the ventilation fan is at the "0" setting, the fan won't blow, BUT if your moving the normal circulation of air from the HVAC intake will give you the impression that a fan is running, depending on what you've got the car set up for. To test this, do it with the car at a complete standstill. The fan should continually increase in both flow rate and volume (noise from it) as you go from 0->Maximum blower rate. It it's stuck blowing in the "0" position, something is wrong.
3. There are two distributors to feed two sparks/piston (like you already pointed out). The sparks don't fire simultaneously. They fire slightly offset from one another. The primary distributor will likely detonate most of the fuel in the piston/cylinder, but the secondary distributor will fire what's left...this allows a slight increase in power and a pretty hefty reduction in pollution related gasses that would have remained unburned.
Good Luck,
Bill Wagner
As far as your questions on the '91 Targa go, here are some answers:
1. The degree of "roughness" of idle is VERY difficult to diagnose over the internet. I have a '91 C4 w/21K on it. At idle, it tends to hang around the 700 RPM mark...once in a while it will surge slightly (maybe about 50RPM, maybe about once a minute). The idle itself is generally smooth other than what I've described.
2. If the ventilation fan is at the "0" setting, the fan won't blow, BUT if your moving the normal circulation of air from the HVAC intake will give you the impression that a fan is running, depending on what you've got the car set up for. To test this, do it with the car at a complete standstill. The fan should continually increase in both flow rate and volume (noise from it) as you go from 0->Maximum blower rate. It it's stuck blowing in the "0" position, something is wrong.
3. There are two distributors to feed two sparks/piston (like you already pointed out). The sparks don't fire simultaneously. They fire slightly offset from one another. The primary distributor will likely detonate most of the fuel in the piston/cylinder, but the secondary distributor will fire what's left...this allows a slight increase in power and a pretty hefty reduction in pollution related gasses that would have remained unburned.
Good Luck,
Bill Wagner