tool

Not sure if I should post this here or in the 24V engine forum.

My truck keeps throwing an overboost code so I replaced the MAP sensor last night but it's no different, the freeze frame data always shows that it is boosti9ng 75 in HG which by my calculation is like 36 psi +. Another member also told me that it's almost 37 psi so I guess I'm not crazy.

My truck is stock.

I don't understand how a stock truck could be making that much boost to throw that code. Even supposing my wastegate wasn't opening shouldn't it defuel before it would make that much boost??

Truck seems to smoke alot too.. I thought my wacky MAP sensor would fix it but no dice yet.....

Any ideas??

I'm thinking maybe I could rig up my temporary fuel psi gauge in a similar fashion to measure boost. Good idea?

Than I would no if it was actually making crazy high boost or if it's an electronic problem elsewhere.

How would I go about rigging it up??

ie. where would I tap into to get a temporary boost reading?

Thanks

MtnCamper

Why go thru all the trouble, buy a real one (along with Pyro temp and FP) then mount them permanent. If you're pulling a big load (Gooseneck 30K lbs.) I would think you would want to know what's going on all the time.

As far as the boost, no idea......

Haulin_in_Dixie

I generally get in trouble for making statements like this, but a pressure gage is a pressure gage is a pressure gage. If you have a cheap oil pressure gage laying around it will measure boost pressure, as well as air pressure, or home water pressure. That also gives you other alternatives.

Pull one off your air compressor. It will work also. To pick it up, any hole you can get into the boost system will work. got a lot of fittings? There is a large pulg on the side of the head near the sensor that will work. Or one of the inner air box bolts can be used to pull pressure. Cummins uses one with a hole in it for their uses and can be purchased from them. Got a lathe, you could jury rig one, drill a hole in it and braze a stub on top to connect a line. I would go ahead and install the cummins bolt and cap it off till you get gages.

Or just drill and tap a 1/8 Npt hole in the intake tube. Anyplace is just about ok. As was said though, you need gages on all the time.

tool

I can't install gauges permanent right now since I'm away from home.

I was thinking I could rig up the gauge I use for my temporary fuel presure gauge (30 psi mechanical liquid filled) I bought it at an oil field supply store.

Just gottta find fittings and a place to tap into.

infidel

On the 24 Valve the boost pressure port is a 3/4" inch pipe plug requiring a 1/2 inch square drive ratchet extension for removal and is located on the side of the intake rearward of the fuel filter bracket.
Pick up a mechanical oil pressure gauge line kit from any auto parts store, it will have everything you need for $10 except except a 3/4x1/8" bushing to go in the block, get that where ever plumbing is sold.

tool

Sweet, thank you. Like I said I allready have all the other pieces except that pipe bushing. Just gotta get the 1/8" x 3/4" NPT bushing and I'll be set.


Well..............

actually then I'll have to see if it's actually making huge boost like that and then figure out why.

Surely that can't be right?? How could a stock truck make that much boost????