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1998 Seville SLS
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1 Posts
Discussion Starter · #1 ·
Hey, guys. I've got a problem with my 98 Seville SLS. I had the overheating problem that are common to the Northstar engines, so I pulled the engine and redrilled the block. It runs well now and doesn't overheat so I think I've got most of my problems with this car solved. Now for the fun. The car now stalls at redlights and sitting in my garage on idle. I have cleared all the codes and the only one that remains is p1520. I have done most everything I can think of to fix this. I have even replace the PNP switch. I can't seem to get it lined up right because no matter what I do, the dash won't register the Park or Neutral posisition. The car starts in both posisitions so I'm confused. The stalling problem is driving me nuts and it makes the car tough to drive. It seems that the RPM's slowly drop down to around 600 and then it acts like someone just turned off the key.
I have driven this car before pulling the engine and it didn't have these problems before. It ran perfectly but just overheated. This is my first Northstar pull and I know that there's just somthing I missed. Thanks in advance for your help!
 

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Administrator
2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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72,793 Posts
P1520 - Transmission range switch circuit.

It's either the main harness connector to the transmission or the switch itself is faulty. Maybe the Internal Mode Switch.
 
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