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PO108 - M.A.P. sensor high input?

12-28-2009, 08:09 AM
So check engine light comes on, head to a partssource, and they tag the following. PO108 - manifold absolute pressure sensor high inputis this something I should swap out before I get some heavy winter weather? I mean, I'm planning on not fixing anything given I've put several thousand in repairs in under a year now, and as such will never buy a gm again, but, is this something that should be taken care of? no abs or traction I can deal with over the winter, same with not always working wipers. I'm assuming the image below isn't what I'm looking for, so if not, where would I find the MAP, and how would I go about fixing this?

12-28-2009, 10:35 AM
Is this a GT or GTP? For a 3800NA in a GT the MAP is on the opposite side of the motor, near the PCV Valve in the UIM. On a 3800SC, the Map is behind the supercharger towards the firewall, near the large alternator bracket. P0108 usually indicates a bad map sensor, but I would check the wiring for proper reference 5V and ground,and I think on the 3800NA motor there may be a rubber grommet or something that over time deteriorates. Also check for vacuum leaks.

Lets move onto your other problems. No ABS/Trac Off lights are usually caused by a bad hub or wiring to. You could ohm check all four hub connectors and compare the four. Otherwise a dealer should be able to hook up a scanner and tell you what hub is bad and needs replacing. We can help you and there is even a write-up in tips and maintenance subforum. Definatly a DIY job.

Check the tips and maintance subforum for the wiper issue too. There is a very simple procedure for fixing wipers that get stuck in the same spot, providing that is your issue.

12-28-2009, 10:45 AM
It's a GT. Speaking foreign to me on the voltage stuff, but I'll give a look around for it and check for vacuum leaks. is this a crucial part or can I survive running the car around for the winter or longer til' I pick up my Charger R/T come spring? As for the trac/abs, mechanic did a scan for me with his high end tool, and said I had 4 ports closed? (something like that) and told me it is most likely the control box under the hood. another guy said it was my right front. not sure which to go for here, but I believe the first guy (did work for me, and is a good friends family mechanic). For the wipers, they randomly stop when used in intermittent or low speed. I mean random. 5 seconds to 5 minutes of use. to make it park or return to working, I have to flick it on hi-speed, which only really temporarily fixes this.

12-28-2009, 11:08 AM
Ohhh! A charger R/T!

As long as there are no drivability issues with it, starts and runs good, accellerates fine, I dont think you should have any problems going untill spring. If it were mine though, I'd replace it. New MAP sensor run about 50.00. Your lucky its not your MAF sensor.

For the wipers, try here, if this sounds sort of like your issue....

12-28-2009, 04:35 PM
Couple things.

I'd check to make sure the MAP is not disconnected from its vacuum. If not, I'd order another one and change it.

A Gen-U-Wine GM Tech 2 can pinpoint what your ABS/Trac problem is. A dealer has one and I'd negotiate a fee to plug it in and check. Then you know for sure and aren't throwing parts at it (generally not a bad idea if you can DIY and understand some of the more common failure modes as those parts likely would need changing sooner anyway - however for limited budget or limited patience I'd want to know for sure). I would usually suspect a wheel sensor or the pigtail wiring damaged by road debris.

12-28-2009, 05:07 PM
The MAP sensor on a NA SII 3800 engine is located right on top of the PCV valve located in the right side of the UIM plenum (Upper Intake Manifold).

Remove the MAP sensor first and check the rubber accordian seal. Also, remove the PCV valve and check underneath where it mounts in the UIM for any signs of coolant. Bad LIM gaskets can cause the P0108 DTC.

Better pic. I just replaced this UIM yesterday.

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