Intake MAP sensors
 

Hey guys,
I think my sotck intake box sensors may be faulty but I wanted to see if any of you might have ideas on this that have worked on your cars yourselves. Dr. Matt and Racehorse, maybe you guys could chime in as well? :)
Anyway, I am thinking one of the sensors may be bad because I have talked to Kleeman and others who say if one of them isn't reading or reporting correctly, it will sne dincorrect boost estimates to the ECU and then the ECU will adjust boost on the other side of the engine to match. I tired ordering some new ones and the had slightly different part numbers, but apparently 'interchanged' which we all know is a crap shoot. Long story short, they were terrible, the car had good power down low to about mid throttle then the boost felt like it hit a brick wall and the car just didnt pull hard. I put the old sensors back in and the old power(pre 'interchange' parts) is back but the car still feels down on power from last season. I have tried some intake redeigns over my ownershiop, had the sensors just hanging oout, unplugged and replugged them 100 trimes, so my question to you guys is, do you see these airbox sensors go bad often? Is there a way to test them? I can't believe how much of a difference these two sensors make in the cars responsiveness and power level when they are only supposed to be measuring vacuum. Am I missing something?

Thanks in advance for any insights!

Broadly speaking, there are two types of MAP sensors - those for naturally aspirated, and those for forced induction engines. There are lots of types of each, and you can interchange quite freely, but you obviously can't use NA sensors on these cars.

Easiest way to get the right part is probably to take what's on your car, read the part number, and search for that number.

Have you got WIS?

Nick

Yeah I have WIS.
I just disconnected the battery, unplugged the sensors, replugged them and reconnected the battery and it is running like a raped ape again.

Last year I tried the Racehorse CAI and loved the results, great throttle response, super top end power and better mileage, for one month. Then it lost all three and ran like garbage. I put the factory boxes back tin and it ran fine again. I had the sensors at that time plugged into their leads and just hanging out in the engine bay. I would love to know how people using a CAI mitigate these sensors as my car simply wont run without them in the factory air boxes for long. Maybe I am just unable to run a CAI system but I am curious how other's car can.

Thanks for help Nick, I appreciate it!
Marc

I might add these and connect the sensors via silicon tube: http://www.siliconeintakes.com/holse...er/-p-500.html

I have not had any issues with my CAI tubes. I have the 2 sensors from the airboxes plugged in but dangling on top near the fuel rail, not stubbed into the intake tubing. There is also another similar looking MAP sensor connected to a small vacuum line off the right side intercooler. This one has a different part# than the other 2 on the intake boxes. Maybe they look the same but measure differently, it might be worth checking if you were given 2 of those instead of the others. I wonder if there is anything to gain by having the 2 airbox sensors instream of the outside air. Good luck.

https://cimg1.ibsrv.net/gimg/www.mbw...8fbaa33807.jpgI ran hoses from the sensors into the intake

Do I see meth inj? Lets hear more!!!!

Any chance your tuner did something to address....its almost as if they overboost without them....I had horrible misfires and then put stock back and its perfect

Slicks and tune got me a 11.3. Just put bigger stall in, built trans (level 10), also have a 100 octane tune I'm gunna run with meth and should get me in the 10s. Meth will be done tommorow 😁

https://www.youtube.com/watch?v=TavwxhZ83SU&feature=youtu.be

heres a video of her in action in her current state of tune (before meth)

You need them (airbox map sensors) to measure the air draw into the turbo. They are super important

No, nothing was done by the tuner as far as I know.

They are not disconnected/unplugged. My understanding is that will cause a problem, but I haven't had issues out fo the stream, it won't be hard to extend and test. I did manage a 10.69 with them dangling. Is it a secondary, using the one after the intercooler as the main reading?

Deleted

It would be really cool to link up at atco! I run there with one of my buddies

Let's see what happens in the fall, temps will be on our side. I have to do private rentals, otherwise I'll get booted.

Sorry OP, any updates resolving your problem?

Let me know, I'm down also Cecil county dragway is an option for private days

So got a misfire with the stock boxes on, all on one bank....then it was fine. One note, on several occasions the misfire occurred when the car was not up to temp yet.....might be a lot of factors.

My issues appears to be related to my tune, only occurs at part throttle accel......took the tune off and couldn't get it to misfire....will try again tomorow

Here is my DTC trigger info
P0300
FLsys1 CL
FLsys2 CL
Load % 42.4%
ECT 208
ShrtFT1 -1.6
LngFT1 4.7
ShrtFT2 0.0
LngFT2 5.5
MAP KPA 105
RPM 2375
VSS(KM.h) 108
Spark -21
IAT 54 C
TP% 28.6%
Air_stat Off