AFR meter
 

I have a Pro Comp Ultra Light Air/Fuel Meter that was fitted before I got the car (95 WRX), trouble is the needle just flickers like hell. How are these wired up , what should I be checking?
Colin

When you say flickers like hell, does it bounce back and forward while normal driving, then go to a green light when on full boost? It is supposed to bounce off boost, as the ECU is searching for a stioch mixture (equal amt of fuel / air combusting) this is called closed loop. When you boot it, the MAF controls the fuelling, rather than the 02, this is open loop, and there should be no more than a couple of the lights lit, at rich end of the gauge.

If its lots of random lights, or not as described above either your o2 or MAF sensor is shagged, and the AFF is doing its job of telling you. More likely the o2 on your MY of car. Wiring is worth a look, but its pretty simple. They also take a couple of mins to warm up on cold start.

MB

I will need to take it for spin to check.....before i would have said it flickers even on boost , but you have put a doubt in my mind:confused:
Thanks for the information anyway ,didn't know thats how it worked.

Appears to work correctly...doh. The needle /light thingy dances about then when you give it a wee bit stick .0.6/0.7 ish afr gauge goes between the top end of the Stoich range and into the Rich, does this sound about right?
Colin

WOT should be quite high.

You should have the middle green on. I forget the scale, but the range of the meter is 0-1v and you need it about on the "I" of rich, about half way into Rich.

Ill try and find the voltages.

MB

Wouldn't say i was giving it Wot , traffic & kids in the car;) enough to have it spool up briefly, just glad it appears to be working.
Getting a K&N panel and D/P to add to the rest of the Magnex system fitted in the near future so I'll need to keep my Eye on it / learn more about it all.For safety would you recommend something like a Scoobyecu set up?
Apart from the TurboXs dumpvalve thats already fitted I dont intend to do any more to the engine , just want reliability and it running at its best.
Thanks for your help and advice.
Colin

Would definately reccomend the Scoobyecu. With the mods you have it will become a very quick car 9compared to standard) but more importantly, you can then run on Optimax alone.

A full decat on a WRX, with Optimax alone is pushing it IMHO. I would either go rempa (which pays for itself quite quickly!) or run it on Opti and booster.

I would definately definately without doubt reccomend a knock link before fitting a remapped ECU. The sccoby ECU is tried and tested, but there have been a few ECU incidents on here recently, where if peopl didn't have a KL, they would have a very dead engine, very quickly. NB, these werent scoobecu related, but down to things missed when mapping a different type of ECU.... Lesson to be learned there!

MB

I'm building 20 AFR meter's this weekend, all with super brite led's, the idea is to mount it on the dashboard and they will reflect on the windscreen so you can clearly see how your mixture is doing. these are the voltages i'm using to set mine up by:

820 RED (LEAN)
840 ORANGE (LEAN)
860 ORANGE (LEAN)
880 GREEN (OK)
900 GREEN (OK)
920 GREEN (OK)
940 ORANGE (RICH)
960 BLUE (V.RICH)
980 BLUE (V.RICH)
1000 BLUE (V.RICH)

Should be Green on WOT, maybe going in to Orange and Blue at a push, if you get a blue light it means more mods needed!.... 8 )