Another problem or two

[ScuttleRX]

Ive just gone to start the car after its been sitting there about a month or so, first problem is the apexi commander is showing 1.2 bar boost before I even start the car, second the car wont start (it turns over and fires but bogs down quickly and stops). Presume as the commander thinks it has 1.2 bar boost its putting in a lot more fuel than it needs?

If anyone can offer any likely causes would be much appreciated.

Also ive just re-fitted my headlights and huge panel gaps have now appeared almost like the lights have shrunk and my passenger seat has started to grow mould....im not having a good day really!

[nikp]

Ok, as I said in the PM to you, i would start with having a sniff around the MAP sensor. Thats where the ECU gets its boost reading from, so you should start there. It's probably not starting due to the reading it's getting from this sensor. So i reckon once you've sorted that out, it should start (As lnog as it's not flooded!)

Mould shouldn't be too much of a problem: that's due to damp. Get some of those water absorbant crystals: they worked wonders on the moisture that was in my FD. Then once it's dried out, the mould will hopefully clean off.

Can;t help with the poor fitting panels though - sorry

[ScuttleRX]

Thanks for the tip matey, i shall get my hands on some of those crystals :)

Sounds like it could be the problem, where abouts is the MAP sensor?

I did a sensor check on the commander but dont really know what I was looking for, if anyone can decypher it I'll post it up

[nikp]

Map sensor is in this image - circled in red.

Yeah, upload what your sensor output screen was - someone should be able to help there. I've got what everything means at home - but not at work with me now! :p

[banned advertiser]

map sensor is on bulk head just to right of manifold, small black bos approx 1"x2" with vacum line going to it.

[ScuttleRX]

Cheers guys i'll go give it a butchers

[banned advertiser]

Doh too slow

[ScuttleRX]

Just checked the sensor, nothing wrong by sight vacuum lead is attached and ive unplugged it and cleaned it up.

The voltages on the commander are...

PIM 4.99
VTA1 0.72
VTA2 1.65
VMOP 1.03
WTRT 3.19
AIRT 3.26
FUEL 4.39
O2S 0.01

on the other side of screen all the abbreiviations has white circles, but these 4 have black HWL, NTR, PAC, CCN

[ScuttleRX]

Gary have you got any map sensors, or can get hold of some, if it turns out I need a new one? Or should I pop down the mazda garage

[nikp]

On the right hand side, all black means is that the switch is on, while white means it's off. It's the lot on the left that you should be interested in: are there any values flagged in black? If not, then the ECU has not noticed any problems.

Once cleaned up, what is the value being shown with the engine off? Should be zero, or thereabouts.

[nikp]

You could also try Jimmy's - but you really want to confirm whether it is the map sensor that is screwed.

are there any members in the Essex area that could help you? I'm not sure when i'll next be coming up to Essex, but if you haven't got it fixed when i do - i could come over and swap out the sensor to see if it makes a difference.

[ScuttleRX]

PIM value was in black, I thought it was just highlighted as it was the first one, soz should of mentioned that :) I did think it was high for engine off, thought that was the value that increased with engine speed/boost/etc

No the boost is still showing 1.2 after i cleaned it up

[ScuttleRX]

Yeah just double checked PIM value is definately in black (not highlighted, doh!). The PIM is the MAP sensor one isnt it? or related to it at least

[nikp]

Not sure - like i say i have the manual at home, and am having trouble finding it on the net.

Can someone else confirm? If it is the map sensor, your problems have probably been sorted quite quickly! :)

[ScuttleRX]

Lovely Jubbly, its funny how being tired can make a small problem seem a huge disaster! I was really cheesed off a little while ago but quite mellow now :) Shouldnt speak to soon but im hoping we've solved the problem :D

I'll take the map sensor off in a while, give it a thorough clean then give it another try. It was quite gungy around it im thinking i may not have cleaned it enough, might shoot some WD40 in there to get any moisture out

[nikp]

Hey, look at this andy - sounds exactly like your problem:

http://www.rx7club.com/showthread.php?t=345664

Oh, and it does look like PIM is the MAP sensor.

[ScuttleRX]

lol, I just stumbled accross that myself :)

Hopefully problem solved then! there is another thing I thought though, theres a bloke in there mentions he had that problem when he unplugged his apexi boost controller, something about it being on a circuit loop. I haven't got the boost controller but I have got electrical boost gauge which I recently unplugged cos it wasnt working (its one of those ones which the control box), im am 90% sure I drove the car after that was unplugged so hopefully can rule that out. MAP sensor seems the way to go :)

Thanks for the help :)

[nikp]

No, i really don't think the electronic boost gauge will have anything to do with it. All that does is take a reading from the same sensor - in fact that may be why you thought the boost gauge had failed - because the map sensor was on it's way out.

[ScuttleRX]

ah, good point, it did fail gradually, started to waver then didnt show a reading at all, could have been the map sensor dying off, suprised it didnt affect driving characteristics though...still, I think its what todays problem is :) Might get a new one even if I can get old one working, providing Mazda dont require too many limbs for it :)

[ScuttleRX]

Morning chaps,

I swapped the map sensor over yesterday with a new one and unfortunately the pim voltage is still flagged in black, didnt get chance to try and turn it over as I fried the battery charger before it got fully charged up, but as pim is still showing 4.99v and in black no point really.

Any suggestions for next place to check. The problem has only occured from being sat for a few months, im guessing its something thats corroded or got damp as it was fine beforehand.