mattn124

Just went back and read this again. Looks like I might have a problem there since the reading I took was .065V with the key on

Any suggestions? Weak signal,, hope it's not a bad PCM...

Thanks

AggieJustin

Well, the reading on the signal wire seems low. The TST instructions state that a '99 should read 0.5V with key on and engine off, you're reading was 0.065V.

Check your reading between the Orange wire and the Black/Light Blue. This should read 5V as the supply to the MAP sensor.

mattn124

I checked the orange wire to straight ground and got 4.98 V key on

It wasn't to the other wire,, but it was ground

AggieJustin

OK, that checks out.

Then I'm thinking that it's a bad MAP sensor. The only part that doesn't make sense is that I thought as boost increased, the voltage output on the sensor wire increased. I was really expecting that your MAP signal was going to read high which caused the computer to see higher than expected boost.

But maybe the MAP is screwed up and when you get boost, it jumps to a high voltage reading.

mattn124

Thanks for the info and help!!

got any info for me on that loose ground wire?

AggieJustin

Pardon the bad angle...the AFE box is in the way. But is this it?

mattn124

YES!!! That's it exactly!!!!

THANK YOU!!!!!

I mounted it in the right spot, except I put it on the back side of the computer, I'll pull that screw out and put it in right tomorrow morning.

Heading to a somewhat local Cummins shop in St. Louis sometime tonight to get a new MAP sensor, luckily they are open till midnight.

Thanks again for the help,, if there were some kinda "rep" points or something on this board I'd sure give ya some!

raydocks

hi there i just had a friend hook his computer to my truck after installed an airdog setup and he was showing me the map sensor on the rightside of the engine ? not the small black box i see on your engine but it screws in to the block like a temp.sensor. how about letting me know if this is correct.

AggieJustin

The MAP sensor is on the driver's side of the engine, just behind the fuel filter housing.

The pictures I had included earlier were showing a ground location at the PCM.

12valvin

Hey guys what was the outcome on this problem? I'm having very similar issues.

Thanks

I have an 01 2500 auto