Ls/vetc turbo Integra. Fuel cuts at 3psi. Boost cut set at 10.8psi. All sensors are fine according to datalogger, no check engine. Stock MAP sensor. Problem came in gradually Runs well under 3psi.
Anyone seen something like that?.

 

What engine management?

 

Yeah, probably blown up

 

I'M using Crome.
Engine and turbo are fine mechanically.

 

So chipped ECU and not running Demon or Smanager?

 

Nope. Still on the break in street tune actually. Setup has just a few thoursand km ( strrtched on 4 years) on it and ran with vtec disabled most of the time. Ran well at 10psi until last year when this started to emerge. Then turbo was leaking in the exhaust. Fixed it, got it checked and balanced so turbo is ok.

 

Is it a certain rpm that it cuts at or is it just anything over 3lbs. Is the speedometer working?

 

^^

 

Speedo is fine. If I feather the throttle to get a steady 1-2psi it will get over 5000rpm before bucking but WOT it will cut as soon as it get to 3psi.

 

What's your plug gap?

 

try another map sensor or aftermarket map sensor.

 

Tried another stock MAP. I have a 4 bar hondata map but I would have to start the tune all over and I just want to sell the car for the buyer to tune it as he wants.
Didn't check the spark plugs as it really doesn't feel like an ignition problem but I did notice that the fuel pressure drops to 0 when stopped for a day or so and I have to cycle the key a few times to build pressure else it doesn't start first time. Walbro pump.

 

I still say its the Map sensor, try downloading the base tune again and upload it and see if that cures it, I would check the wiring to the Map but it sounds like a Map sensor issue. Possibly your tune has become corrupted with the EMS your using or a capacitor has failed. Try uploading the tune again as I mentioned. Try another EMS or barrow someone's Hondata and try a base map provided by Hondata for a turbo setup, change the map and injector settings to match and try that and see if it cuts. Another thing is oil can find its way in the map sensor and foul it out and cause a boost cut, has happened to me using a stock map and Hondata map. I rolled up a thin piece of napkin and stuck it in the map sensor nipple and it was soaked in oil, after getting the oil out it was fine till it filled back up after a few pulls or driving, I'm now using a catch can.

 

After revewing the datalogger I realized that 5000 rpm is more the constant than 3psi. I actually hit 5psi a few times. So my next step will be to find a complete distributor and eliminate my MSD ignition with crane external coil. And check the plugs...

 

What RPM does VTEC change over ???

 

It's disabled in the tune for now.