Rodney87GN
Well-Known Member
- Joined
- Feb 1, 2004
- Messages
- 1,931
...a few weeks ago. At the time it happened so fast I didn't know what caused it...wasn't paying attention to the gauges or scanmaster. Just taking a test drive after finishing up installing a complete Autometer gauge set into a GNX style panel. I got up to 26 psi of boost (just to make sure the boost gauge works :biggrin: ) and that's when I popped the passenger side head gasket.
Fast forward to yesterday. I finally got everything fixed and running good. Primed the ALKY and set the boost controller on low boost...time to go for a test drive. I ease into the gas and get to about 6 psi. The green alky LED is NOT coming on! I bring it up to 10 psi, still no light.
Uh-oh, I think I just figured out why I blew a head gasket a few weeks ago.
Since the alky primed with the test button, I figured it had something to do with the MAP sensor. Then it just TOTALLY dawned on me....when I did my GNX dash conversion, the MAP sensor no longer gets its 5V or ground anymore. Razor even tells you this in the instruction manual.:redface: Unfortunately I installed my Alkycontrol kit a long time ago before I did the dash conversion, so I didn't even think about it.
I followed the directions in Razors kit to supply 5V to the MAP but took it one step further. Rather than run the wiring in the engine bay I did it inside under the dash. I ran a wire from pin C14 on the ECM to pin B (gray/blk) at the clear connector behind the glove box. This supplies 5V from the TPS gray wire to the MAP sensor. And I ran a separate ground for the MAP sensor from pin G (blk/wht) at the same connector behind the glove box. 30 minutes later, it works like a champ.
Sooo, chalk it up as a lesson learned...no one else's fault but my own. And for those doing an aftermarket dash with Razor's alky, don't make the same mistake I did!
Fast forward to yesterday. I finally got everything fixed and running good. Primed the ALKY and set the boost controller on low boost...time to go for a test drive. I ease into the gas and get to about 6 psi. The green alky LED is NOT coming on! I bring it up to 10 psi, still no light.
Uh-oh, I think I just figured out why I blew a head gasket a few weeks ago.
Since the alky primed with the test button, I figured it had something to do with the MAP sensor. Then it just TOTALLY dawned on me....when I did my GNX dash conversion, the MAP sensor no longer gets its 5V or ground anymore. Razor even tells you this in the instruction manual.:redface: Unfortunately I installed my Alkycontrol kit a long time ago before I did the dash conversion, so I didn't even think about it.
I followed the directions in Razors kit to supply 5V to the MAP but took it one step further. Rather than run the wiring in the engine bay I did it inside under the dash. I ran a wire from pin C14 on the ECM to pin B (gray/blk) at the clear connector behind the glove box. This supplies 5V from the TPS gray wire to the MAP sensor. And I ran a separate ground for the MAP sensor from pin G (blk/wht) at the same connector behind the glove box. 30 minutes later, it works like a champ.
Sooo, chalk it up as a lesson learned...no one else's fault but my own. And for those doing an aftermarket dash with Razor's alky, don't make the same mistake I did!
