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MAP sensor question?

Nosferatu49534

Nosferatu49534

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I've been getting dtc's for the boost/map sensor on my truck since I bought it. I finally got around to getting a new acdelco part from Amazon. The new one that I bought has different notches/ key ways the the one on my truck even though it's supposed to be for my truck. Would the sensor still function properly if I just make slits in the plug on the truck to match the new sensor?

5f10f34a94b794b1e72feb9c55004f5f.jpg
 
Sounds like you ordered a map sensor instead of a boost pressure sensor. The 6.5 uses a 2 bar map, or a boost pressure sensor as some call it. What part number did you order so we can verify which one you got? If you did get a 1 bar map, it will not read boost pressure, and won't work.
 
I didn't realize there were different "models" persay of sensors. After reading your post on pretty sure that I got the 1 bar. So I will returning it. I'll get one from rock auto I think. Thanks for the info. :)
 
Yep, you bought the 1 bar MAP sensor, or the one that is mounted to the firewall on 94-95 trucks, and 96+ with an EGR valve. You need 213-1545. It's actually a cheaper part on AMAZON.
 
Well I ordered the part 213-1545 and the plug still doesn't match what I have on my truck. Could I get a different pigtail and switch the one on the truck? Or notch my pigtail to match the new sensor? Here's pics of the new sensor and old and my plug on the truck.

8c3021ff8159892a374de2a37bc05e26.jpg



Old
176b8f622d35fadcfd3d7ed8df8a4da6.jpg



New
aa73f3e0bed534c1ee6d636008ffe050.jpg
 
I ordered a generic 3-bar map sensor from ebay, like $7-10 IIRC. Came with a new plug that I spliced in. No more overboosting DTCs.
 
Well I have an update. Apparently it was not the map sensor that's been the problem. It was the boost solenoid. While I was installing my boost gauge a couple weeks ago I happened to pull on one of the plastic vacuum lines and it cracked, so I decided to run all new rubber ones. While doing that I noticed there was a hole that had been rubbed through one of the plastic lines as well. I figured I would double check the whole system there and still wasn't getting any vacuum to the diaphragm on the waste gate. So I hooked the vacuum line straight from the pump to the diaphragm and holy crap turbo was workin over time. Figured it had to be the solenoid. Bought a new one slapped it on and now, with my boost gauge I can read the boost bleed off around 2200 rpm like it should and kick back in. No more dash lights as well.
 
Not sure if this is a sound theory or not but I was thinking this morning while on my way home if I have a 2 bar map/ boost sensor and it opens the waste gate at around 2400/ 2500 rpm would putting the 3 bar open it at a higher rpm? Its not more boost that interests me, just getting the boost at a higher rpm. For example while going down the highway at 65 - 70 I'm at 2200ish, so as soon as I push the pedal down to speed up I'm at 24 to 2500 and all that boost is gone. Or is the boost not needed in that rpm range?
 
Going to a 3 bar map would increase you overall boost pressure. The wastegate doesn't open at a preset RPM, and I guarantee you the wastgate solenoid is opening LONG before it hits 2400-2500 RPM's. It should begin to open as soon as boost spikes to around 9 or so, then drop back to 7 or so at sea level(at altitude it will open at higher boost pressure as the system uses total pressure, not just boost). So unless your hitting really high intake air temps, you should hold 6-8 pounds of boost all the way up to redline under power.
 
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