ECMlink No Start, Dead MAP Sensor w/ SD

[MattHDSM]

Hey there DSMers, I've run into an intermittent no start condition which I believe I have pin-pointed down to the MAP sensor. It's a mitsu style Omni 4 bar, about 3-4 years old by now. I have checked timing, spark, and fuel. Didn't get the chance to check compression before I killed the battery, but it randomly ran fine yesterday after getting towed back home, so I'm going to make the (unwise) assumption and say compression is good without checking. The no start is when I turn the car over, it "fires" once and immediately dies.

Today, I noticed in my logs that the sensor is reading -28.9 inHg of vaccuum with the car off and while cranking. If I apply pressure to the top of the sensor, it reads 0.1 psi which makes sense given the car isn't running and sitting at atmospheric pressure. Unfortunately for me, I don't have a second pair of hands around to test cranking while applying pressure to the sensor.

I'm new to running speed density so my question to you guys is if the following makes any logical sense. I turn the car over, it "fires" once and immediately dies because the MAP sensor is reading no pressure. No pressure means the ecu thinks there is no air and doesn't send any fuel. No fuel, no bang, car dies.

Please let me know what you think, Thanks.

 

[jed344]

-28.9 is what it will read if not plugged in. Make sure everything has a good connection otherwise that could be a dead sensor. A speed density car will not run without proper working map sensor.

 

[MattHDSM]

-28.9 is what it will read if not plugged in. Make sure everything has a good connection otherwise that could be a dead sensor. A speed density car will not run without proper working map sensor.

I didn't know that that value was its unplugged value. As far as I can tell, the plug and the sensor contacts are contacting, but I'll confirm that tomorrow just to rule out a bad connection. Thanks

 

[Mello]

The MAP sensor is fairly easy to do a check on. remove it from the intake, add a piece of vacuum hose & connect it to a pressure &/or vacuum source while watching the sensor output on Link.

 

[Vegas Smith]

Who would have thought an Omni sensor would stop working? I literally see a thread a week about these things.

 

[ThunderChild]

Who would have thought an Omni sensor would stop working? I literally see a thread a week about these things.

Indeed. I'm fed up with mine. None of the 3 brand new sensors I have work. Even have the ECMtuning PNP buffer cable, have tried it hardwired passed the cable etc. Far as I'm concerned these things are garbage. I'm looking for another solution currently.

 

[jakk220]

Yep. I have had multiple issues with the Omni 4 bar par sensor as well. On the bright side if you call them they will warranty it out. Another easy way to test is hook up a factory MAF and change the ECMlink settings to see if the car will start. But mine did that exact thing and it was a bad sensor. Call Omni and have them send you a new one.

 

[Evolving_sti]

Who would have thought an Omni sensor would stop working? I literally see a thread a week about these things.

Absolute trash. That's why they have a lifetime no questions asked warranty. I switched to an aem 3.5 bar. Working lovely since.

 

[MattHDSM]

Yep. I have had multiple issues with the Omni 4 bar par sensor as well. On the bright side if you call them they will warranty it out. Another easy way to test is hook up a factory MAF and change the ECMlink settings to see if the car will start. But mine did that exact thing and it was a bad sensor. Call Omni and have them send you a new one.

I had no idea they warrantied them like that. I already bought and installed a new one, car fire up immediately so problem solved, but a working spare wouldn't hurt to have around.

 

[jakk220]

I had no idea they warrantied them like that. I already bought and installed a new one, car fire up immediately so problem solved, but a working spare wouldn't hurt to have around.

If you have a spare id keep an 8mm wrench and the spare in the glove box . They give out with no warning.