Hi everyone

I'm having an issue with my car. The boost doesn't seem to go above 17.4 PSI with the 61mm pulley. We should be seeing 20-22 PSI in boost.

The map sensor is showing around 29PSI and the ZT2 boost sensor is showing 17.4PSI. I think the reading is kind of strange meaning that the atmospherical pressure should be about 11.6PSI(strange). But I can see in the log that sometimes the ATM is 11.6 compared to the Zt2 boost but other times around 15-16PSI. How come that it can vary that much. Shouldn't these sensor be exact or maybe the vacuum leak is giving me this errors.

I have replaced my map sensor yesterday which seemed to give me wrong readings. The car is running much better with the new map sensor but the issue remains. The boost won't go over 17.4 PSI.

I have ordered a leak tester and put it on the TB. I used our own little compressor we have in the trunk for pumping in the air but according to my zt2 boost sensor the pressure doesn't seemt to go over 8.7 PSI and I can hear a leak. The leak is coming from the brake boost pipe. How come that we have a leak in the break boost pipe in the TB house? When I push it in all the way after the click sound it still has 1-2mm movement. I'm I missing some kind of O-ring? What I have heard from Rob there is no O-ring on the brake boost pipe.

Have anyone else have this problem? Have anyone checked there leak before?

How can I check for vacuum leak? Even with the new map sensor I'm getting the CEL P1107. Three people seems to say the same thing that is that the error can occur if there is a vacuum leak.

What is the best way to check for vacuum leak?

So I'm having two problems:

- Positive boost leak, possibly to seal the boost pipe in the TB house will fix the issue
- Vacuum leak which is giving me the CEL P1107 error code

Need some good advice

Have a nice one

 

Nobody has any ideas???

 

Not me! Even with boost/vacuum leaks at the manifolds my sensor always read full boost. The only places for leaks I can think of that would cause low boost at the sensor are:
Supercharger outlet to Y pipe
Y pipe to manifold: right/left
Supercharger to intercooler gasket
Usually, if you have a serious leak in those areas the idle will be really high, perhaps up to 4000 rpm. I pulled the intake and covered the throttle body with my hand and my rpms didn't drop, huge leak. Good luck and patiently start trouble shooting to narrow down where the culprit lies.

Les

 

Maybe a dumb question, but have you checked for belt slippage?

 

Are you running stacked? I glanced at your datalog but didn't see MPH. FYI, from experience max boost is going to happen in 3rd gear or higher.

I'm kicking myself now, as I don't believe I updated the thread when I installed a new tune and saw higher boost from that alone. More timing for some reason gave me more boost. I'll update things tomorrow.

It's been crazy at work, but I'll try to update the thread tomorrow. In the meantime, keep in mind, max boost doesn't happen in low gears.

 

adam, please connect the laptop to the zt-2 and ensure that it is set to read the 3.5bar map, we may have a setting off

 

Hi Rob,

Thanks, I will double check this setting

 

Hi,

Thanks, I have been thinking of this also. Will be checking this in the weekend.

/A

 

Hi,

There has been questions about what OEM map sensor I used that is capable of 3.5bar. Here it is:

Bosch 0261230193,0261230143. MB A0061539928

Hope this helps others

/A

 

If you used A0061539928 in place of the A0051537228, and you did not reprogram your ECU to re-scale the signal, then that is your problem. Both sensors operate at 0-5v. So, the same PSI in the new and old sensor will translate into a different voltage readings and will confuse the ECU.

 

Hi,

You are absolutely right about this. I have reprogramed the ECU though.

Thanks for the heads up

/Adam

 

Isn't MB A0061539928 MAP sensor rated at 3 bars, not 3.5 as stated by you above? Who did you use to reprogram your ECU?

 

stock map sensor is 2.5 bars absolute, the 006 153 99 28 is a 3 bars sensor for diesel, can u please tell us who remap ur car for a 3 bars map instead of 2.5 bars??? are u sure that this part nb is now installed on ur SRT6 and running fine!!!

 

from EPC:
IMAG0727.jpg

 

Hi,

You are absolutely right, it is 3 bar map sensor and NOT a 3.5 bar map sensor as I stated before .

 

I'll have to check my MAP p/n as well, most I've ever logged with my 61mm pulley is 18.8 psi

 

I'm getting the CEL P1107 saying that the map sensor circuit voltage to low. Does somebody else having this issue? I have read in different forums about bad ground leading to that the 5v feeding voltage to the map sensor is below 4.75 volt. I will try to measure the feeding current this weekend.

Could it be that the Zeitronix connection is leading to a voltage drop? I have actually connected the zeitronix ground to the ground on the ECU. Maybe this is wrong.
I will try to disconnect the Zeitronix and check if the CEL goes away.

Need all the help I can get

 

No CELs for me, I have attributed the early "low" readings to belt slip. Aluminum makes a lousy surface for traction, given the low coefficient of friction (relative to steel). Now that I have some miles on the pulley, the slip seems to be less than before and the car will absolutely put you back in the seat at WOT

 

My readings are about 19.8PSI which is actually ok. But the CEL P1107 that I'm getting doesn't seem to come from a boost leak it seems that the feed voltage to the map sensor is to low. I'm wondering if this could be because of the Zeitronix with all the sensors that are connected to the same ground wiring on the ECU, hmmmm. Just a wild guess, that is why I would like to try to disconnect the Zeitronix to start with then do a diagnostic measurement on the map sensor according to the Crossfire manual.

 

Makes total sense... wires are wires, at the end of the day. If you load too many things on a small gauge wire like that, it can affect the items at the end of it (MAP sensor, in this case).