Falls on face after sitting hot then fine....
#1
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99 fbody ks1/t56 swapped into a 85 BMW.
I have noticed that if the car sits for a short period of time, say 10minutes, when I take off again I will get a stumble. Today it almost stalled...would not rev past 1500....
But maybe 10 seconds later it will be fine. Or if I drive slow for a bit it is ok too.
I have an SLP maf and am using the iat in the maf. I was wondering if it could be getting heat soak? Should I run a separate iat?
My intake is a 90 degree bend then 3.5" steel pipe to the maf and then to a cone filter.
I am taking the car on a 600mile trip starting tomorrow so would like to try and fix this before if possible. Or at least maybe know the cause.
I have HP tuners so if I have time later tonight I am going to log it a bit and see what the iat reading.
Tia
I have noticed that if the car sits for a short period of time, say 10minutes, when I take off again I will get a stumble. Today it almost stalled...would not rev past 1500....
But maybe 10 seconds later it will be fine. Or if I drive slow for a bit it is ok too.
I have an SLP maf and am using the iat in the maf. I was wondering if it could be getting heat soak? Should I run a separate iat?
My intake is a 90 degree bend then 3.5" steel pipe to the maf and then to a cone filter.
I am taking the car on a 600mile trip starting tomorrow so would like to try and fix this before if possible. Or at least maybe know the cause.
I have HP tuners so if I have time later tonight I am going to log it a bit and see what the iat reading.
Tia
#2
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IAT while driving are about 5-10 degrees above outside temp. It is 95 out today....
Logging around 100 or so while driving.
After sitting for 20 minutes in the garage with the hood closed my IAT is at 155 degrees. It was climbing while I was sitting idling as well.
The intake pipe before the maf is reading 175 after sitting for 20 minutes and checking with a IR meter.
Logging around 100 or so while driving.
After sitting for 20 minutes in the garage with the hood closed my IAT is at 155 degrees. It was climbing while I was sitting idling as well.
The intake pipe before the maf is reading 175 after sitting for 20 minutes and checking with a IR meter.
#5
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Just to update this...I figured out the issue. The gas tank did not have a vent so I want either getting a bit of vapor lock or the tank was actually pulling the fuel back from the feed line after shutting it off.
I cracked the cap and now I haven't had the issue again.
I cracked the cap and now I haven't had the issue again.