Is that wagon or MY specific is it?

Because it's a new one on me. After nearly 4 years i've never heard of anyone having to replace the MAP when fitting a chip.

 

When your soldering the resistor back in put an inline switch in it then you can have a low and high boost setting. If you get further problems and you suspect its the chip you can flick the switch and run the factory ecu, saves stripping it all down again.

 

well its a 93 saloon and the chip ran 16.6psi as stated which is 1.15bar which is more than the std map sensor can sense so it will fail on a regular basis i changed 3 on mine beforefitting the 2bar after market one problem solved . in fact i think the chips just remove the fuek cut alltogether because mine has hit 19psi and ignition cut in very cold weather,

 

Off to maplin then

 

One of the things I'm trying to work out is if I say floor it in 2nd gear it only hits 1 bar, though if I do it from low revs in 4th or 5th it hits 1.2 bar and cuts out.

Should it theoretically be hitting 1.15 bar in all gears no matter what the load is?

 

Think you will find the OE MAP is 1.2bar(17.4psi), so if the sernsor is fit it should not fail. My OE MAP sensor cuts at 18psi.

If you have had 3 MAP sensors on your car, i would say you have a under laying problem, or you've been buying duff sensors. I've been told, by a very reliable source, that if you upgrade your MAP, then you must have the MAF rescaled to suit .

My genuine PP chip certainly does not totally remove the fuel cut, you see my map was designed to run within the OE safty features, including those of the MAP sensor. It mearly raises these limits within the safe parameters. And thats tried and tested for plenty of years.

I can't comment on the Map on your chip as i don't know anything about it.


On a fit/well maintained car you should see max boost being made in 3rd upwards. High RPM+high boost is not good, that is why most maps tail off the boost higher up in the rev range.

 

Would tie in with the 1.2 Bar cutoff on my wagon ..

Cheers info helps!

 

Was this simple to wire in?
Thanks Steve..

 

Yes there should be clicking from that area, the BCS. It should also click during normal runnig. If it is not, then that could be part of the problem. A good flush through with brake/clutch cleaner usually does the job.


Changing MAP Sensor

 

you have to buy the wiring adapter 3.99 makes life easy . fuel cut on a early wrx i thought was 14.78psi ignition cut at 19psi ( i may be wrong ) . the map sensor gives out the same voltages as oem so many milliamp per psi of presure sensed , it says on thier website its to suit a cossie but the voltages are the same as a gredey one for a scoob , when fitting pm me and i will tell you what wires connect to the oe wiring, if you want to fix the overboost problem on the cheep just fit a mbc and set it to 16psi

 

[B] Is the chip not suppose to raise the cut limit to just above max boost? (1.1bar)

Quote:

Originally Posted by Major_Sarcasm

1. Raise boost level with factory boost control solenoid (no need for aftermarket boost controller) to 1.1 bar (~16 psi).
2. Adjust fuelling and timing to suit UK super unleaded fuels (97 RON) (conservative, economical settings for cruise, but safe settings for boost).
3. Update firmware of ECU to Z4 (the latest version).
4. Raise fuel cutoff level to just above max boost.
5. Finally, will give reliable everyday power (~280bhp conservative estimate) and more economy on normal off-boost driving.

O yes, so it says!

So madscooby, you pay £100 for a chip that 'is compatible' with your car.

So why then, do you you have to spend another £30 on a MAP sensor, then another £4 on a wiring converter??
If thats not enough bo11ox, you then advise the OP to 'mask' the 'unknown' problem with a cheap MBC..
If i have a problem/issue, i choose to find and fix it, not spend more money 'hiding' it. And, if as you are claiming, your boost cut limit has been totally removed, then yes, tick, tick tick

 

i didnt pay 100quid for it and thats not the point the point is the map sensor is minus 1bar plus 1bar oem 16.6psi is 1.15bar the std map sensor can only give the correct voltage to the ecu for up to 14.4psi after that the ecu is guessing the ignition and fueling . all the way to 16.6psi that why i fitted a +2bar map sensor , car runs a lot better now am just waiting for another rolling road day at ajs . and on a final note if you cant afford 34quid to make a scoob safe on the cheep then you shouldnt own one . 240bhp to 297 for less than 600quid thats all mods including chip . i could of course spend another 1100.00quid and get a simtek for another 30+40bhp BARGAIN not , as for the chip removing the fuel cut it doesnt i was just saying that in cold weather it will overboost without a mbc to control it

 

[QUOTE=madscoob;9630499]...the point is the map sensor is minus 1bar plus 1bar oem 16.6psi is 1.15bar the std map sensor can only give the correct voltage to the ecu for up to 14.4psi after that the ecu is guessing the ignition and fueling . all the way to 16.6psi[/QUOTE

Don't talk bollox! OE fuel cut is 1bar.


[QUOTE=madscoob;9630499].....if you cant afford 34quid to make a scoob safe on the cheep then you shouldnt own one.....

If you fit cheap (that means cheap inexpensive, not cheep tweet tweet) 'incompatible' mods, and then bodge them to mask the incompatibilities, perhaps you should not own one either .

 

[QUOTE=b13bat;9630527][QUOTE=madscoob;9630499]...the point is the map sensor is minus 1bar plus 1bar oem 16.6psi is 1.15bar the std map sensor can only give the correct voltage to the ecu for up to 14.4psi after that the ecu is guessing the ignition and fueling . all the way to 16.6psi[/QUOTE

rtDon't alk bollox! OE fuel cut is 1ba.


yes the std fuel cut is 1 bar ie 14.4 psi and therfore the 1bar std oem map sensor is also 1bar . when you fit chip and raise boost to 16.6psi = 1.15bar that is beond the ability of the map sensor all ime saying is it aint just a plug and play chip thats all there is more to fitting them than meets the eye and to stop overboosting you need a 2bar map sensor either newer oem one (cant remember which my ) or a after market one . my mates has simtec and all sorts of mods 2.5conv 386bhp if i remember right and his has a 2bar map sensor of the grededy brand . i checked the voltages and they are the same as the 30quid one thats all . the oe post was why am i getting code 45map sensor . the reason he is getting this code is simple he is running more boost than the map sensor is capable of reading (ie he is demanding more voltage from it than it can give ) that is why code 45 is coming up on his scoob , the answer to that prob is to fit a 2bar map sensor thats all i said / as for dangerous heres the list of mods to mine
chip
headers and up pipe
full decat
walbro pump
ind kit
last time it was on rollers std clutch was slipping at anything over 12psi so limited it to 11psi at which it was 289bhp i have the graph somewhere but martyn at ajs said it was running sweet if a tad rich .8 on co he said i would have more power on .7 so remove the 440 injectors i have and it runs milkes better and has done from 80500miles all the way to 118362 at the moment

 

FFS, the OE MAP sensor is good for 1.15bar. The chip is said to give 1.1bar(15.95psi) and the fuel cut is said to be raised just above that, 1.15bar (16.65psi) would be a sensible cut point as that is the MAP sensors limit.

Therefor, if the chip is producing over 1.1bar and causing cut then it is not mapped correctly. This will happen when people copy things, it looks like you can squeeze a little more out, but in fact this is not possible. When i fitted my PP chip to mt MY93 saloon i had to make no more changes, it was, as advertised, plug and play. This puts paid to your 'more than meets the eye' theory.

Why would you let your car boost to 1.3bar (19psi) if you believe the fuelling is 'geuss work' from 0.99bar (14.4psi). If these where indeed the facts, even with the aftermarket MAP fitted you would still require some rescaling to ensure the AFR's where correct.

Long and short of it is, the chip, if mapped properly, should not cause the car to hit boost cut. As per my car.

So your 'fuelling was fine all the way up the range' comment is worthless, as you only ran to 12psi

Perhaps, instead of wasting your cash on incompatible mods and masks, you should save you pennies and get a decent clutch fitted.

 

just done the clutch n lightweight flywheel thanks to bob now running 16.6 and going much better . i cant be arsed to argue but i sell electronics at work for a living heres the data on said sensor the voltages are the same as subaru use . all i was saying was that a 1bar map sensor is just that 1bar after that it wont give the correct voltages thats all
A 3 bar map sensor suitable for turbo applications upto 2 bar of boost pressure. It has a standard 3pin mini timer socket (plugs available seperately) and a port for 4mm silicone hose.

The sensor produces an output between 0.25v and 4.75v corrisponding to a range of 17kpa to 308kpa (aprox. 30psi of boost).

The data-sheet for the sensor is available here

Sensors are supplied with wiring (pin function) details.

 

16.6psi (1.14bar), still within the limits of the OE item.

I'm not arguing with you, i'm telling you the facts .

Selling electronics for a living, that qualifies you to copy and paste from a manufacturers web site, very educated.

 

you cant just fit the higher reading map sensor it just wont read correctly.

 

The boost your turbo will make will depend on the load placed on the engine. Your turbo will be capable of full boost in 5th and 4th gear as there is plenty load. It may make marginally less in third but in second it is probably less and in first noticably more so. In effect it is unlikely you will ever make full boost in 1st and 2nd on an older ECU.
On some aftermarket ECUs or more modern OE ECUs there is in gear compensation. The gear the car is in is recognised and wastegate solenoid duty is increased to compensate.

 

to all the input, helping overall comprehension no end. Re an after market 3 bar map sensor, logic of doing this seems ok - if the signal from the sensor is identical, bit of a punt without proof, but experience must count for summit

 

The point i am making is, if the chip is mapped correctly (as per Scott.T's map) and your MAP sensor is healthy then you should not need to change the MAP sensor.


For further comprehension, search "MAF Scale" and read the mappers responses, the likes of Scott.T, JGM, Bob Rawle and Dynamix ect.

 

Just a little point to help you guys. The ambient pressure is 1 bar. ie normal pressure on earth around sea level is 1 bar. Your boost guage measure pressure above ambient. So if you are 1 bar on your boost guage that is 2 bar absolute. Map sensors are usually referred to in absolute pressure so a 3 bar map sensor allows you to run 2 bar and a 4 bar map sensor will allow you to run 3 bar if you want.
The sensors operate on an output of 0-5Volts.
MAP = Mean Air Pressure.

 

Thanks Harvey, i understand absolute pressure.

So,
If a 2 bar sensor is at 2.5 volts thats 0.5 bar, above ambient. (5v=2bar absolute)

If a 4 bar sensor is at 2.5 volts thats 1.5 bar, above ambient. (5v=4bar absolute)

Correct?

But all the ECU sees is 2.5v, which it has been pre-programmed (mapped) to interprate as 0.5 above ambient and will only fuel to these requirments?

Correct?

Therefor, if i have all the above correct. When you fit a higher capacity sensor then you must have the map and/or MAF rescaled to recognise the changes, because as you pionted out Harvey, the sensors all work on an output of 0v to 5v.

2bar Sensor: WOT=5v=1bar aa.

3bar Sensor: WOT=5v=2bar aa.

What does the standard ECU fuel for at 5v??

Unless you remap it, it does not know that you have changed the sensor.

 

Did anyone solve this problem as my car does the same thing with the same chip???
Help!!!

 

Are you getting the 45 fault code??

 

no,i dont get the 45 code but in 4th and 5th the car overboost and fuel cut.
i have cleand all the pipes and boost solenoid but nothing

what should i do???

 

Right, you will need to give us all the info on your car, MY/mods etc.

Have you checked for codes at all??

 

So...the car is a my93 wrx imported.
I have a fault code from about a month ago after drove the car from Romania to England and back.The code is 22 Knock sensor,but the car ranned fine till now.

Mods:Fmic,induction kit,equal headers and up-pipe,full de-cat 3'',major_sarcasm chip.

In major_sarcasm post someone told me to clean the maf with brake cleaner and the car will be fine again.(he cured this porblem like this)