I have bougth a sierra cosworth 4x4 which was sold to me as having a stage one chip. After changing the standard actuator for a -31 item I tried to adjust the boost.

What I noticed was that anything peaking above 17 PSI the ECU shut down everything. So now I have adjust it to peak at 16 PSI and holding 14,5 PSI and the limiter on the ECU doesn't come in.

But is this a standard chip as on my previous cosworth with standard chip it only could peak at 13,8 PSI most before the limiter came in. (held max was 11,6 PSI).

And if not how does the ECU know that the boost exceeds 16 PSI as it has a standard 2 Bar mapsensor (I think)?

Hope someone (Stu?) can help me with this.

YBJ

 

That sounds like a stage 1 chip to be honest....

 

sounds like a stage1 to me

 

I think standard map can read up to 18psi, but not 100% sure, but does sound like a stage 1 chip.

 

Than I don't understand how the ECU can tell what the boostpressure is anything above 14,5 PSI??

 

Or can you tell on the numbers on the chip if it is standard or not?

It is a cos 4x4 redtop engine from 1991.

 

Are you sure you havent got an overboost pressure swicth in teh plenum or intake elbow area? Often has 2 wires going to it.

 

Yes I am sure, because recently I have had that section of the engine when putting on some new engine mounts. And I didn't see anything special up there.

 

Stu, do you have any other suggestions ? Does it sound like a standard chip to you?

 

hi
if the map sensor is half black/grey then its a 3 bar, all black is usually standard, ive never seen a standard chip boost to 18psi either..there are no bleed off pipes etc been fitted on the actuator/amal valve is there??
(i had that once and when i peaked at 18psi the car nearly put me through the windscreen!!!)

 

Double checked everything yesterday and also no bleed pipes anywhere, just plane standard pipe work like it left Ford.

Will look at the mapsensor, I can remember a standard has a character with '3' in it and a 3 bar mapsensor not... Does any know the right numbers on it?

I ones had before a black 3 Bar mapsensor. The guy I got it from told me that it was very special as it was a motorsport item. Usely they are grey indeed.

 

 

2-bar sensor part# APS02/03
3-bar sensor part# APS05

2bar standard sensor is specified to +16.8psi max at full scale output (4.75V)

 

Thanks richm, good answer . So a 2 Bar mapsensor can sense up to 1.15 Bar.
Next thing I need to now what the max boost for a standard chip is (where the limiter comes in) and with that I can see if it is stage one or not.

 

So is the early on mentioned 13.8 PSI indeed the limit for a standard chip?

 

any chip can measure up to the limits of the map sensor fitted (so long as its the correct map for the chip, simply plugging a 3bar onto a standard or stage 1 will not allow it read to 2 bar for example. it will be unable to interpret the signal it receives correctly).
as such a standard chip can measure up to 1bar above atmosphere (and -1bar vaccum hence the 2bar designation).

where the difference lies is in how the chip are mapped to deal with these readings.
a standard chip is set to run with boost of 0.7bar, about 10psi. anything above this is outwith its optimum range and it cannot adjust fueling to take advantage of this extra pressure up until 1bar limit where it will shut off....rather suddenly. its very possible to wind up your boost with a standard chip to the limit of 1bar, the chip can after all read it and the extra pressure certainly makes it feel quicker. the issue is that it will most certainly run lean and will also be less than optimum

using a stage 1 chip will adjust the settings so that boost can be increased to this 1bar ceiling AND the fueling etc is increased to deal with this. this results in more power and better performance since readings are all within an accepted range.

as such you cant use the boost reading on your car purely to gauge if its been chipped or not. a reading of 1bar, the max setting for stage 1, would be an indication that it was chipped however since the boost setting is a mechanical function and entirely independent theres many other factors that could be contributing instead, ranging from a fault or leak to simply a previous owner increasing boost with little regard for the car itself.

why dont you just take a look at the ecu. if its never been opened its safe to say its not chipped. if it has been why not open it up and look at the chip thats in there. it should quickly become apparent as to whats in there or not.

 

I have had the ECU out and indeed it has been opened by the previous owner. So what should a standard chip has voor charactars on it that I can refer to?

And the maximum boost it shut down is 16 PSI (1,1 Bar)

 

its easyer iif you take a photo of the inside

 

this is what a standard unmolested L8 looks like:



standard L3E31 red-top chip:

 

i dont think ive ever seen a standard chip

 

that's the ECU we used on the Zetec Gareth - I've never seen one with the cover seals intact before either! and we trashed it!

 

good work

 

tbh I wouldn't even risk it keep the boost down get it to a decent tuner and have it checked and setup properly.
you here to many horror stories about people messing with boost etc only to find they bugger the engine as a result

 

ok thanks guys, will check the numbers this evening and then post a picture of it!

 

Here is a picture of my ECU:



As you can see, it says something different on this chip.

"COSW 4048 MA4" if I am correct.

Anyone any idea if this is a standard chip? This cossie was imported from Italy.

 

 

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