maxing out 3bar map sensor
Thread Starter
Cruising
Joined: Jan 2007
Posts: 12
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maxing out 3bar map sensor
Using efi live with 3bar sensor. Maxing sensor out a 255kpa at 5200rpm then car goes into power reduction mode. No codes are present. wondering if computer is maxed out at 255kpa. All help and opinions are appreciated.
thanks
thanks
Melting Slicks
Joined: Nov 2004
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From: Tinker till it blows... then back it off a notch, maybe!!
St. Jude Donor '08
hpt guy here, so not much help...maybe you have a 2.5 bar map sensor???
Have you ever seen 3 bar?...you could test with 30 psi air line
Have you ever seen 3 bar?...you could test with 30 psi air line
Thread Starter
Cruising
Joined: Jan 2007
Posts: 12
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At 5200rpm the pid is reading 255kpa then 300rpm later it goes into pr mode. Trying to figure out if the pcm is maxed out at 255kpa or if its the sensor. It has never read higher than 255kpa but i can watch the boost gauge and it continues to increase. So if the 3bar is good to 310kpa do i need to change something in the pcm.
Thanks
Thanks
Le Mans Master
Joined: Oct 2003
Posts: 8,863
Likes: 86
From: PA
St. Jude Donor '08
At 5200rpm the pid is reading 255kpa then 300rpm later it goes into pr mode. Trying to figure out if the pcm is maxed out at 255kpa or if its the sensor. It has never read higher than 255kpa but i can watch the boost gauge and it continues to increase. So if the 3bar is good to 310kpa do i need to change something in the pcm.
Thanks
Thanks
yes is in your scanner section...you need to choose 3 bar
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Le Mans Master
Joined: Oct 2003
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From: PA
St. Jude Donor '08
Burning Brakes
Joined: Feb 2004
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From: over the water Cali
Need more info about set up? what engine, what hp. You can check the output of the 3 bar sensor relatively easily with a volt meter. 5v system. Does the voltage increase beyond the software reading 255kpa or does it hold at say 4 volt or has it already hit 5 volts and the MAP is really a 2.5 bar map.(strange because if it were a 2.5 bar MAP you would just read 310kpa when you really were at 255kpa).
That should narrow it down to the scanner or ECU.
That should narrow it down to the scanner or ECU.
Supporting Vendor
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From: http://www.mphparts.com 800-364-1975
Thread Starter
Cruising
Joined: Jan 2007
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As far as more info on my set up: 98 vette 408 9:1, L92 heads by TPIS, L76 intake,cam 238 248 605 615 on a 115, kooks 17/8-2 step headers, magnafuel fuel system,ram street twin, F2 procharger non intercooled on E-85. The reason the boost is so high is because of the restrictive intake and the small cam.We're in the 4 digits at about 6000rpm, but it keeps going into pr mode.
Melting Slicks
Joined: Nov 2004
Posts: 2,715
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From: Tinker till it blows... then back it off a notch, maybe!!
St. Jude Donor '08
Part number is 12223861 and im pretty sure its an acdelco sensor.
As far as more info on my set up: 98 vette 408 9:1, L92 heads by TPIS, L76 intake,cam 238 248 605 615 on a 115, kooks 17/8-2 step headers, magnafuel fuel system,ram street twin, F2 procharger non intercooled on E-85. The reason the boost is so high is because of the restrictive intake and the small cam.We're in the 4 digits at about 6000rpm, but it keeps going into pr mode.
As far as more info on my set up: 98 vette 408 9:1, L92 heads by TPIS, L76 intake,cam 238 248 605 615 on a 115, kooks 17/8-2 step headers, magnafuel fuel system,ram street twin, F2 procharger non intercooled on E-85. The reason the boost is so high is because of the restrictive intake and the small cam.We're in the 4 digits at about 6000rpm, but it keeps going into pr mode.
not familiar with efi live, but I would check voltage vs boost...could just need a custom pid, but first you need to know that the map is or is not putting out the correct voltage.
Last edited by RJW; Oct 2, 2007 at 09:34 PM.
Drifting
Joined: Aug 2005
Posts: 1,314
Likes: 3
From: Simi Valley CA
I ran into the same thing on my Starion. I switched to a 3.5 bar map and was able to boost to 35 psi. They also sell 5 bar map sensors, but the resolution is not so good. They are only for race cars. I got mine from SSI technologies. You can get one from AEM also. Good luck.
Melting Slicks
Joined: Jun 2002
Posts: 3,060
Likes: 3
From: Dublin CA
I took the stock 1bar MAP sensor from the back of my LS1 manifold and was about to plug it into the front of my L76 manifold. I noticed the seal was wasn't tight. Is this common?
Also, is the 3bar MAP sensor a direct fit to the L76, or does it use a vacum hose connection?
Also, is the 3bar MAP sensor a direct fit to the L76, or does it use a vacum hose connection?