Hey guys,

Just curious if anyone has seen this one before.
I have a Omni 4-bar MAP sensor that I use on other cars i'm tuning for ECU boost.
Its always read fine on mine and 10+ other cars i've used it on to date, however a car I started tuning tonight is reading all over the shop.
I've plugged it back into my own car and checked it prior to posting and its reading normal on my car, so I doubt its the sensor.

At idle its reading ~1.8-2.3 psi, at 100 load, 3psi and ~18psi up top compared to the mechanical gauges ~16psi.

On every other car, including my own, its always read ~-6.5psi at idle, 0psi at ~95 load.

Car is a 2.3 (first one i've tuned) which shouldn't affect anything i'm assuming as pressure is pressure. The car also won't connect 90% of the time on the 1.3U cable, I have to use a 2.0 cable.

Car is a JDM 7...

Cheers
Ben

 

Ok a bit of Google action seems to point toward it being a grounding issue...

Does that stick?

 

Is it scaled correctly in EcuFlash and in evoscan?

 

Yeah i've been using this sensor on 10-15+ other cars that I have tuned without issue, this is the first, however the 1.3u cable is dropping out randomly, won't connect randomly.
Wondering if this is the same reason.

 

What version of tephra was the 7 tuned on originally and what cable was used?

 

I have heard nothing but bad stuff about omni map sensors, mine died about 10k miles after installing. Went to an aem.

 

I've had mine for over 20k miles and still working like a champ. How long ago did you purchase yours?

 

I'm currently having an issue with mine as well, went out after 2 months of use. Car suffers sudden rich/lean afr spikes when cruising/taking off and when those afr spikes come on the car feels like it's about to stall.

Omni is sending me a new 4 bar as we speak, I also made a thread about it in the Engine/Turbo section so feel free to comment.

My friend who tuned me just recently also noted how my current 4bar , which is brand new had odd boost readings. Car did throw a CEL for a faulty MAP sensor, but went off a day later. But the car still has the same afr spike symptons.

 

ive never heard of them failing before.. must be very rare. 80% cars i tune are equipt with them too.

the 4 bar map does not read vacuum at idle neither do the others on evoscan.

if its not setup properly with the proper equations its not gonna read right period.

also you have to disable periphery bits or it will throw cels.

 

Was purchased through MAP.

I know how to set the rom up.
It's not via Periphery on JDMs either.
I know it reads vac differently as well.

It's just this car and I proved its not the sensor as I plugged it into my own car straight after last night and the same equations I've always used is reading correctly in Evoscan as always.
Car has recently had the engine replaced due to a few inspection holes in the block so I'm curious if a earth has been missed or something along those lines.

 

Car has just been converted to 90550701, was running 98640014 as a base rom and the 1.3u cable had issues on that rom as well.

 

I have the 1.3U cable and omni 4 bar on the 90550701 ROM, it read the same as the GM 3bar I use to have, as I had them both plumbed in at the same time for a while. Have you checked the MAP test voltages in the ROM?

 

Maybe I misunderstood something here, but in my experience it is not exactly so. 4 bar MAP sensor reads 0-4 bar absolute pressure (with ambient pressure being ~1 bar. Everything else is a matter of scaling. But with correct scaling which shows you boost pressure, it will show you vacuum at idle, being -0.5...-0.6 bar (which is 0.4...0.5 bar absolute pressure in the intake manifold) for more or less stock EvoIX.

 

Yeah it shows vac, just in a different scaling.

Something fishy going on Marcel, 2.0 cable cutting out half way through 3rd gear WOT pulls, suddenly idle is crisp smooth 1500 rpm, instead of ~1000.
Park idle stepper motor, parks fine, then cuts out after 5 sec with FTxx (can't remember) error in the Evoscan dialogue.
Plug 1.3u in, same thing, plug 2.0 in suddenly fine.
Each time the idle went up to 1500, became crisp and smooth, the map sensor would start reading correctly (~ -6psi at idle), then when the revs dropped, went lumpy and then the map sensor would go back to reading 1-2psi at idle.

I'll get him to go over everything and rewire/check earths, remove things that aren't required etc.

I've only ever seen it once before, on a 5RS.

 

who said you set the rom up via periphery? i was responding to someone elses response that was saying they had cel's.. infact, my entire response was based around other responses in here not your original one.

if you tried it on your own car and its not the sensor then its a electrical issue clearly.. time to get the multimeter out and start checking stuff. and yes improper grounding can cause all kind of electrical issues in a car.

what roms on your car? and what roms on this car?