Engine/Transmission (1998.5 - 2002) MAP Codes?

[JTHosler]

Well a couple days ago the check engine light came on, so I used the smarty to check the codes. The PO236 and PO238 codes were thrown. I cleared them and they have not come back, but yesterday I was trying a few things and noticed with my comp on I could only get about 20lbs of boost (40 Normal). With the comp off I would push 35 or so which is normal without the comp. My question is could a bad comp cause the codes and low boost or do iI have something else going on? Oh and even after playing around yesterday the check engine light didn't come back on and i don't have the codes back.



Thanks,

 

[JLandry]

Justin,



It might be a simple case of your MAP sensor has gone bad. Since they're not very expensive and easy to replace, you might want to try that first.



Good luck,



John L.

 

[JTHosler]

Update

I am going to have someone look at the connections then try the MAP sensor. I have been watching and have gotten the check engine light 2 more times this past week. Same codes PO236, PO238, and 1475 I believe. This time when the light is on the comp won't turn on at all. Could this be a bad comp or as simple a connection or map sensor? When I clear the codes the comp seems to work fine until the light comes back on.



Thanks,

Justin

 

[darkhorse]

Coincidentally, my CEL started coming on right after I tapped the pump wire of my HRVP last week, but I get P0237 (low voltage) instead of your high voltage codes. I clear the codes but they come back seemingly at random. My question is the same though: MAP sensor failure or something in the APB? Something else? The truck seems to run fine.